APPLICATIONS***


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Transcriber's note:

      Text enclosed by underscores is in italics (_italics_).

      Page 151 Illustration Fig 9 contains an alphabetical list
      of components with "F" designating "Clock" and small "F"
      designating "Film". This latter designation for "Film"
      has been indicated in the text by "=F=".





PRACTICAL CINEMATOGRAPHY AND ITS APPLICATIONS


       *       *       *       *       *

_BY THE SAME AUTHOR._

Price 6_s._ net each.

MOVING PICTURES: HOW THEY
ARE MADE AND WORKED.

LIGHTSHIPS AND LIGHTHOUSES.

THE STEAMSHIP CONQUEST OF
THE WORLD.

THE RAILWAY CONQUEST OF
THE WORLD.


LONDON: WILLIAM HEINEMANN.

       *       *       *       *       *


[Illustration:

 _By permission of the      Motograph Co._

HOW TO TAKE MOVING-PICTURES OF WILD ANIMALS IN SAFETY.

Messrs. Newman built a huge dummy cow fifteen feet in height of
papier-mache. The operator stands inside with his camera and the
pictures are taken through a small hinged door. With this "property"
dangerous animals can be approached closely.]


PRACTICAL CINEMATOGRAPHY AND ITS APPLICATIONS

by

FREDERICK A. TALBOT

Author of "Moving Pictures" etc.







[Illustration]

London MCMXIII
William Heinemann

Copyright.




PREFACE


This volume has been written with the express purpose of assisting the
amateur--the term is used in its broadest sense as a distinction from
the salaried, attached professional worker--who is attracted towards
cinematography. It is not a technical treatise, but is written in such
a manner as to enable the tyro to grasp the fundamental principles of
the art, and the apparatus employed in its many varied applications.

While it is assumed that the reader has practised ordinary snap-shot
and still-life work, and thus is familiar with the elements of
photography, yet the subject is set forth in such a manner as to enable
one who never has attempted photography to take moving-pictures.

At the same time it is hoped that the volume may prove of use to the
expert hand, by introducing him to what may be described as the higher
branches of the craft. The suggestions and descriptions concerning
these applications may prove of value to any who may be tempted to
labour in one or other of the various fields mentioned.

In the preparation of this volume I have received valuable assistance
from several friends who have been associated intimately with the
cinematographic art from its earliest days:--J. Bamberger, Esq.,
of the Motograph Company, Limited, James Williamson, Esq., of the
Williamson Kinematograph Company, Limited, Kodak Limited, Messrs. Jury,
Limited, and Monsieur Lucien Bull, the assistant-director of the Marey
Institute, to whom I am especially indebted for facilities to visit
that unique institution, and the investigation at first hand of its
varied work, the loan of the photographs of the many experiments which
have been, and still are being, conducted at the French "Cradle of
Cinematography," and considerable assistance in the preparation of the
text.

FREDERICK A. TALBOT.




CONTENTS


  CHAP.                                                           PAGE

  I.     ATTRACTIONS AND OPPORTUNITIES OF THE ART                    1
  II.    THE PRINCIPLES OF CINEMATOGRAPHY                           13
  III.   THE MOVING-PICTURE CAMERA AND ITS MECHANISM                21
  IV.    THE CAMERA AND HOW TO USE IT                               35
  V.     HAND CAMERA CINEMATOGRAPHY                                 51
  VI.    DEVELOPING THE FILM                                        62
  VII.   PRINTING THE POSITIVE                                      79
  VIII.  ABERRATIONS OF ANIMATED PHOTOGRAPHY                        94
  IX.    SLOWING-DOWN RAPID MOVEMENTS                              108
  X.     SPEEDING-UP SLOW MOVEMENTS                                124
  XI.    CONTINUOUS CINEMATOGRAPHIC RECORDS                        135
  XII.   RADIO-CINEMATOGRAPHY: HOW THE X-RAYS ARE USED IN
             CONJUNCTION WITH THE MOVING-PICTURE CAMERA            147
  XIII.  COMBINING THE MICROSCOPE AND THE ULTRA-MICROSCOPE
             WITH THE MOVING-PICTURE CAMERA                        161
  XIV.   MICRO-MOTION STUDY: HOW INCREASED WORKSHOP EFFICIENCY
             IS OBTAINABLE WITH MOVING-PICTURES                    174
  XV.    THE MOTION PICTURE AS AN AID TO SCIENTIFIC INVESTIGATION  185
  XVI.   THE MILITARY VALUE OF THE CINEMATOGRAPH                   197
  XVII.  THE PREPARATION OF EDUCATIONAL FILMS                      209
  XVIII. PHOTO-PLAYS AND HOW TO WRITE THEM                         224
  XIX.   RECENT DEVELOPMENTS IN STAGE PRODUCTIONS                  238
  XX.    WHY NOT NATIONAL CINEMATOGRAPH LABORATORIES?              248

         INDEX                                                     259




LIST OF ILLUSTRATIONS

                                                                FACING
                                                                  PAGE

  How to take Moving-pictures of Wild Animals in safety
                                                    _Frontispiece_
  A Moving-picture Expedition into the Indian Jungle                 4
  Polar Bear Diving                                                  5
  A Lion and Lioness at Lunch                                       10
  Caught!                                                           11
  Operator and Camera buried in a Hole                              14
  Making Moving-pictures of Wild Rabbits                            14
  Nest of King Regulus, showing curious Suspension                  15
  Mother King Regulus feeding her Young                             15
  The Jury Moving-picture Camera                                    24
  The Williamson Topical Camera and Tripod                          25
  The Williamson Camera threaded for Use                            42
  Lens of the Williamson Camera                                     43
  Adjustable Shutter of the Jury Camera                             43
  The "Aeroscope" Moving-picture Hand Camera                        52
  Compressed Air Reservoirs of the "Aeroscope" Camera               53
  Lens, Shutter, Mechanism and Gyroscope                            56
  Loading the "Aeroscope" Camera                                    57
  Mr. Cherry Kearton steadying himself upon a Precipice             58
  Mr. Cherry Kearton slung over a Cliff                             58
  Vulture preparing to Fly                                          59
  A Well-equipped Dark Room showing Arrangement of the Trays        64
  Winding the Developing Frame                                      65
  Film transferred from Developing Frame to Drying Drum             72
  Film Wound on Frame and placed in Developing Tray                 73
  The Jury Combined Camera and Printer                              73
  The Williamson Printer                                            84
  Water Beetle attacking a Worm                                     85
  Marey's Apparatus for taking Rapid Movements                     112
  Cinematographing the Beat of a Pigeon's Wing                     113
  First Marey Apparatus for Cinematographing the Opening of a
      Flower                                                       128
  First Motion Pictures of an Opening Flower                       129
  Development of a Colony of Marine Organisms                      129
  Continuous Moving-picture Records of Heart-beats                 136
  Continuous Moving-pictures of Heart-beats of an Excited Person   137
  Continuous Cinematography--Palpitations of a Rabbit's Heart      142
  Stero-motion Orbit of a Machinist's Hand                         143
  Lines of Light indicating to-and-fro hand Movements              143
  A wonderful X-ray Film made by M. J. Carvallo                    148
  Moving X-ray Pictures of the Digestion of a Fowl                 149
  Stomach and Intestine of a Trout                                 152
  Digestive Organs of the Frog                                     152
  Lizard Digesting its Food                                        152
  X-ray Moving-pictures of the Bending of the Knee                 153
  X-ray Film of the Opening of the Hand                            153
  Micro-Cinematograph used at Marey Institute for investigating
      minute Aquatic Life                                          164
  Micro-cinematography: The Proboscis of the Blow Fly              165
  Micro-cinematograph used at the Marey Institute                  170
  One of Dr. Comandon's Galvanic Experiments with Paramoecia       171
  Micro-cinematography: Blow Fly eating Honey                      176
  The Ingenious Gilbreth Clock                                     177
  Rack, showing Disposition of Component Parts, for Test           177
  Film of Workman assembling Machine                               182
  Film of Rack and Bench, Floor marked off into Squares, and
      Clock                                                        182
  Cinematographing a Man's Work against Time                       183
  Moving-pictures of a Steam Hammer Ram                            188
  Dr. Fuech's Apparatus for taking Moving-pictures of the
      Operations of a Steam Hammer                                 189
  Wonderful Apparatus devised by Mr. Lucien Bull for taking
      2,000 Pictures per second                                    190
  Moving-pictures of the Ejection of a Cartridge from an
      Automatic Pistol                                             191
  Motion Photographs of the Splintering of a Bone by a Bullet      191
  Soldiers Firing at the "Life Target"                             204
  Front View of the "Life Target" showing Screen Opening           205
  Screen Mechanism of the "Life Target"                            206
  Cinematographing Hedge-row Life under Difficulties               207
  Moorhen Sitting on her Nest                                      212
  The Young Chick pierces the Shell                                212
  Chick Emerging from the Shell                                    213
  Newly Hatched Chick struggling to its Feet                       213
  Chick, Exhausted by its Struggles, Rests in the Sun              214
  The Chick takes to the Water                                     214
  Fight between a Lobster and an Octopus                           215
  Story of the Water Snail                                         215
  The Head of the Tortoise                                         218
  The Hawk Moth                                                    218
  Snake Shedding its Skin or "Slough"                              219
  The Snake and its Shed Slough                                    219
  Exterior View of Dummy Cow                                       226
  Mr. Frank Newman and Camera hidden within Tree Trunk             227
  Lizard with Spider in its Mouth                                  240
  Digestive Organs and Eggs of a Water Flea                        241
  Moving-picture Naturalist and the Lizard at Home                 241
  A Novel "Hide," with Camera Fifteen Feet above Ground            250
  "Hide" Uncovered showing Working Platform                        251


IN TEXT

  FIG.                                                            PAGE

  1.  Mechanism of Camera showing Threading of Film                 28
  2.  The "Pin" Frame                                               67
  3.  The First Picture of the Four-spoke Wheel                     97
  4.  Apparent Stillness of Spokes while Wheel is Moving            98
  5.  Apparent Backward Motion of Spokes while Wheel is
          Running Forwards                                          99
  6.  When Wheel is seen to be Moving Naturally                    100
  7.  Curious Illusion of seeing Twice the Number of Spokes
          in the Wheel                                             102
  8.  Mechanism of the Nogues Camera                               115
  9.  The Ingenious Radio-cinematographic Apparatus devised
          by Monsieur M. J. Carvallo                               151
  10. Dr. Comandon's Radio-cinematographic Apparatus               157




PRACTICAL CINEMATOGRAPHY




CHAPTER I

ATTRACTIONS AND OPPORTUNITIES OF THE ART


Profit and pleasure combine to win recruits for the art of animated
photography. As an entertainment offered to the public, the
moving-pictures have had no rival. Their popularity has been remarkable
and universal. It increases daily, and, since we are only now beginning
to see the magnitude of what the cinematograph can effect, it is not
likely to diminish. This development has stirred the ambition of the
amateur or independent photographer because the field is so vast,
fertile, and promising. Remunerative reward is obtainable practically
in every phase of endeavour so long as the elements of novelty or
originality are manifest. The result is that it is attracting one and
all. Animated photography can convey so fascinating and convincing a
record of scenes and events that many persons--sportsmen, explorers,
and travellers--make use of it.

From the commercial point of view the issue is one of magnetic
importance. In all quarters there is an increasing demand for films of
prominent topical interest, either of general or local significance.
The proprietors of picture palaces have discovered that no films draw
better audiences than these. If they deal with a prominent incident
like a visit of royalty to the neighbourhood, an important sporting
event, a public ceremony, or even, such is human nature, with some
disaster to life or property, they will make a stronger appeal for a
few days than the general film fare offered at the theatre, because the
episode which is uppermost in the mind of the public is what draws and
compels public attention. Even, it would seem, when the reality itself
has just been witnessed by the audience, its photographic reproduction
proves more attractive than all else.

The picture palace, indeed, is assuming the functions of the
illustrated newspaper, and is governed by like laws. The more personal
and immediate the news, the more pleased are the beholders. So there
is an increasing effort to supply upon the screen in life and motion
what the papers are recording in print and illustration. One can almost
hear the phrase that will soon become general, "Animated news of the
moment." Already the French are showing us the way. In Paris one is
able to visit a picture palace for 25 centimes at any time between
noon and midnight and see, upon the screen, the events of the hour
in photographic action. As fresh items of news, or, rather, fresh
sections of film, are received, they are thrown upon the screen in the
pictorial equivalent of the paragraphs in the stop press column of the
newspapers, earlier items of less interest being condensed or expunged
in the true journalistic manner to allow the latest photographic
intelligence to be given in a length consistent with its importance.

It is obvious that this branch of the business must fall largely into
the hands of the unattached or independent worker, who bears the
same relation to the picture palace as the outside correspondent to
the newspaper. A firm engaged in supplying topical films cannot hope
to succeed without amateur assistance. No matter how carefully and
widely it distributes its salaried photographers, numberless events
of interest are constantly happening--shipwrecks, accidents, fires,
sensational discoveries, movements of prominent persons, and the like,
at places beyond the reach of the retained cinematographer. For film
intelligence of these incidents the firm must rely upon the independent
worker.

Curiously enough, in many cases, the amateur not only executes his
work better than his salaried rival, but often outclasses him in the
very important respect that he is more enterprising. Acting on his
own responsibility, he knows that by smartness alone can he make way
against professionals. Only by being the first to seize a chance can
he find a market for his wares. Thus when Bleriot crossed the English
Channel in his aeroplane it was the camera of an amateur that caught
the record of his flight for the picture palaces, although a corps of
professionals was on the spot for the purpose. True, the successful
film showed many defects. But defects matter little compared with
the importance of getting the picture first or exclusively. Similar
cases exist in plenty. The amateur has an excellent chance against the
professional. His remuneration, too, is on a generous scale. The market
is so wide and the competition is so keen, especially in London, which
is the world's centre of the cinematograph industry, that the possessor
of a unique film can dictate his own terms and secure returns often
twenty times as great as the prime cost of the film he has used.

[Illustration:

 _By permission of the            Motograph Co._

A MOVING-PICTURE EXPEDITION INTO THE INDIAN JUNGLE.

Mr. Cherry Kearton, the famous cinematographer of wild animals, and his
outfit loaded upon an elephant.]

[Illustration:

 _By permission of the            Motograph Co._

POLAR BEAR DIVING. A STRIKING MOTION-PICTURE.]

The market is open also to travellers, explorers, and sportsmen. These,
with a cinematograph camera and a few thousand feet of film, can
recompense themselves so well that the entire cost of an expedition
may be defrayed. An Austrian sportsman who roamed and hunted in the
North Polar ice fields received over L6,000 ($30,000) for the films he
brought back with him. Mr. Cherry Kearton, who took pictures of wild
life in various parts of the world, sold his negatives for L10,000 or
$50,000.

Scientific investigators are in the same happy case. When their
researches lead them to anything that has an element of popular appeal,
there is profit awaiting them at the picture palace. The life of the
ant, for instance, or electrical experiments, or interesting phases of
chemistry, and many other features of organic and inorganic science,
yield good returns to the scientist with a camera. Such films will
command 20_s._ ($5) or more per foot of negative.

There is another branch of the work already well established. The
producer of picture plays, if his plot be tolerably good and the scenes
well acted and well photographed, and if the play itself promises
some popular success, can command a good price. At the moment there
are several independent producers at work throughout the world. They
have a large open market for the disposal of their wares and find no
difficulty whatever in selling all they can produce. Even the largest
producers, who have huge theatres and command the services of expert
scenario writers and players, do not hesitate to purchase from outside
sources.

A cinematograph camera, and a little luck, will make anyone's holiday
profitable. The travelling amateur penetrates into places overlooked
by the professional, and usually takes greater pains with his work.
Afterwards he finds his market in the fact that the demand for travel
pictures is so great that a good film of 300 feet will fetch L40
($200) and upwards. At home he may exploit his ingenuity in making
trick films, a most popular feature at the picture palaces, so long as
he keeps novelty to the forefront. Trick films, unfortunately, take
so long to prepare and demand such care, skill and patience that the
largest firms of producers as a rule are not eager to attempt them,
because their production disorganises the more regular and profitable
work of the studio. A good trick film of 800 feet may occupy six
months in preparation. But the amateur may approach what the large
firm fears. To him time is no object, and he is able to maintain his
interest, care, and ingenuity to the end of the quest. On the other
hand the professional worker often tires of his trick subject before
the task is half completed, with the result that novelty and care are
not sustained. One industrious Frenchman devoted nearly a year to
the preparation of a film in which resort had to be made to every
conceivable form of trickery, and sold his product for L3,000 or
$15,000. He also refused an offer of L5,000 ($25,000) for another film
of pictures calculated to please children.

To sum up, the amateur or independent cinematographer has a vast field
available for the profitable exercise of his skill. Except in regard to
the topical work, which is of the rush-and-hustle order, he must show
imagination in his choice of subject and craftsmanship in the execution
of his work. He must, that is to say, be trained so far as to be no
longer an amateur in the popular meaning of the word. He must learn
aptitude in the school of experience. The reward is well worth the
trouble.

Hitherto the amateur worker has been held back by the great expense of
the necessary apparatus. The camera cost L50 ($250), and the developing
and printing operations were generally supposed to be too difficult
and costly for private undertaking. There was some excuse for these
notions. The trade at first followed narrow lines, no welcome being
held out to the amateur competitor. But circumstances have been too
strong for this trade, as for others, and it burst its bonds in due
time. The co-operation of the independent worker became essential
as the demands of the market increased. In the production of plays,
for instance, England at first led the way. But the American and
French producers came quickly to the fore. The English pioneers,
not being skilled in the mysteries of stage craft, wisely retired
from the producing field upon the entrance of the expert from the
legitimate theatre, who realised that the moving-picture field offered
him increased opportunities for his knowledge and activity as well
as bringing him more profitable financial returns for his labours.
The British fathers of the industry devoted their energies to the
manufacture of cinematographic apparatus, as they foresaw that sooner
or later the amateur and independent worker must enter the industry.
The activity of amateurs was needed by the English trade as a whole,
and the manufacturer, with great enterprise, brought down the cost of
apparatus to a very reasonable level. This has been effected by methods
not less advantageous to the purchaser than is the reduction of the
price--by standardisation of parts and simplification of mechanism.

To-day a reliable camera for living pictures, suitable for topical
and other light work, can be bought for L5 or $25. A more expensive
camera, the Williamson, costs L10 10_s._ ($52), and is actually as
good as other machines priced at four or five times that sum. On the
other hand, so much as L150 ($750) can be paid. But the camera sold for
this large sum demands a purchaser with something more than a long
purse. It demands special knowledge. Designed for studio work, it has
peculiarities that are difficult to master and is not to be recommended
to a beginner.

With the cost of the camera the cost of other apparatus has fallen
in proportion. It was realised that the amateur's dark room and
other facilities are likely to be less excellent than those of
the professional and that he must be provided with compensating
conveniences. This problem has been solved. A complete developing
outfit can now be packed in a hand-bag, and a camera and printing
outfit can be carried in a knapsack no larger than is required for
the whole-plate camera of the old "still-life" photographer. Simple
and efficient appliances for the dark room can be purchased very
cheaply. There is a portable outfit for use in field work, where it is
imperative that films should be developed as soon as possible after
exposure, and this outfit is now used by the majority of travellers
and field workers, such as Cherry Kearton, Paul Rainey, and others.
Distinct advantage, it may be observed, comes from prompt developing.
There may be vexatious delay, occasionally, but the photographer is at
least able to tell quickly whether his film is a success or a failure.
It is better to gain this knowledge on the spot, even compulsorily,
where another record can be taken, than to gain it later a few
hundreds of miles from the chance of trying again.

The capital expenditure of the cinematographer need certainly not be
great. A complete outfit, the "Jury," may now be obtained for L20 or
$100. It comprises a combined camera and printer, developing troughs,
film-winding frames for developing and drying, and all necessary
chemicals. Yet it is no toy, as might be thought, but a thoroughly
reliable outfit capable of doing first-class work. Anyone who is
more ambitious, or willing to spend more money, should purchase the
Williamson outfit. This costs about L40, or $200.

Now for other difficulties that have nothing to do with money. It
has been assumed that the art of animated photography is a mystery
demanding a long and weary apprenticeship. But the impression is
really quite wrong. Anyone who has practised still-life and snap-shot
photography may become proficient in the new art within a week or two.
Many of the problems encountered in the old photography are actually
easier to solve in the new; some are eliminated entirely; others, that
are intensified, are really not very hard to master.

[Illustration:

 _From the "Cinema College," by permission of the      Motograph Co._

A LION AND LIONESS AT LUNCH.]

[Illustration:

 _By permission of the Motograph Co._

CAUGHT!

A jungle-fowl brought down by a leopard.]

Animated photography is nothing more than a Kodak worked by machinery.
Instead of the shutter being actuated by hand to make an exposure,
and the film afterwards moved by turning a roller so as to bring a
fresh area before the lens, the two movements, in the cinematograph,
are combined. The rotation of the handle alternately opens and closes
the lens, and moves the film forward a defined distance after each
exposure. Therefore, speaking generally, if the beginner knows how to
use an ordinary camera and is familiar with subsequent operations of
developing and printing, he should be able to accustom himself quite
readily, with little waste of material, to the different conditions of
motion photography.

There is practically but one process that he should not at first
attempt. This is the perforation of the film. The film is a celluloid
ribbon and is punctured near either edge, at intervals, so as to enable
it to be gripped by the claws of the mechanism and moved forward
intermittently a definite distance--three quarters of an inch--through
the camera. This puncturing or perforation of the film is the most
delicate of the whole cycle of operations. It can only be done by
a machine of unerring precision manipulated with extreme care. The
machines, though many are on the market, are somewhat expensive, and it
is upon them that the steadiness of the picture on the screen depends.
The inaccuracy in the perforation may be slight, a minute fraction of
an inch, but it must be remembered that each picture on the film is
magnified more than fifteen thousand times upon the screen, and the
errors are magnified in proportion. But these considerations need not
trouble the amateur. He can purchase his "stock," as the unexposed film
is called, perforated ready for use.

In spite of the great reduction in the cost of both camera and outfit
the expense of cinematography is still its drawback. The film is the
culprit. It costs from 2_d._ to 4_d._--say, from 4 to 10 cents--a foot.
Yet in this case, as in others, reduction seems to be within sight.
The increased demand is sure to cheapen the process of production.
If the price is not then lowered as much as could be hoped the cause
will be in the cost of the basic materials. These also, perhaps, will
become less dear in time. Cinematography is an industry in revolution.
Its possibilities are only beginning to be seen; its followers are
only beginning to be counted; but it can hardly be doubted that the
ranks of the amateur and independent workers are certain to increase
considerably and rapidly. The attractions and inducements to practise
the craft are too alluring to be ignored.




CHAPTER II

THE PRINCIPLES OF CINEMATOGRAPHY


For complete success in moving-picture work it is essential to have an
elementary knowledge of the principles upon which the art is based.
Although pictures are said to be shown in motion upon the screen, no
action is reproduced as a matter of fact. The eye imagines that it sees
movement. Each picture is an isolated snap-shot taken in the fraction
of a second. In projection upon the screen, however, the images follow
so rapidly one after the other and each remains in sight for so brief a
period that the successive views dissolve into one another. The missing
parts of the motion--the parts lost while the lens is closed between
the taking of each two pictures--are not detected by the eye. The
latter imagines that it sees the whole of the process of displacement
in the moving objects. In fact it sees only one-half--the half that
occurred in those fractions of seconds during which the lens was
open. What occurred while the lens was shut is not recorded. Animated
photography, therefore, is an optical illusion purely and simply.

The fact that an appearance of natural movement is seen under these
conditions is due to a physiological phenomenon which, for the want
of a better explanation, is termed "persistence of vision." This
peculiarity of the eye and brain remains a scientific puzzle, and
although in one or two quarters the theory of visual persistence is
ridiculed, the iconoclasts have not yet brought conclusive testimony to
upset it. The whole subject of persistence of vision in its relation
to moving-pictures is discussed at length by the present writer in
a former book to which he would refer such readers as may wish for
information on this subject.[1]

[1] See "Moving Pictures: How they are made and worked," Chapter I.

[Illustration: OPERATOR AND HIS CAMERA BURIED IN A HOLE TO TAKE
MOVING-PICTURES OF SMALL ANIMALS.]

[Illustration:

 _By permission of the Motograph Co._

MAKING MOVING-PICTURES OF WILD RABBITS.

Mr. Frank Newman with his camera concealed in the bushes.]

[Illustration:

 _From the "Cinema College," by permission of the Motograph Co._

THE NEST, SHOWING CURIOUS SUSPENSION BY FOUR STRINGS.

A UNIQUE PICTURE. THE MOTHER KING REGULUS FEEDING HER YOUNG.

Motion-pictures of the Golden-crested Wren, the smallest bird in the
British Isles.]

The eye is about one million times faster than the most rapid
sensitized emulsion which chemists have yet produced. So there is
nothing wrong about the popular opinion that the organ of sight is
the quickest of the senses. Yet it is not so quick that it cannot
be deceived. If the pictures of a cinematograph are projected upon
the screen at the rate of so many per second, the effect upon the
eye is that of perfectly natural movement. The laws that govern this
illusion have been discovered in a very interesting way. A positive
film was prepared, but between each successive image a wide white
line was inscribed. This film was then passed through the projector,
and the pictures were thrown upon the screen at the speed generally
accepted as being necessary to convey the effect of natural movement;
but animation could not be produced at all, however rapidly the
pictures were projected. The reason was simple. Immediately after a
picture disappeared from the screen the white flash occurred, and
notwithstanding its instantaneous character it was sufficient to wipe
out the image of the picture, which without the white line would have
lingered in the brain. Even when the pictures were run through the
projector at thirty per second, no impression of rhythmic movement
was obtained; they appeared in the form of still-life pictures with
spasmodic jumps from one to the other. They failed to blend or dissolve
in the brain, notwithstanding that the white flash in some cases was
only about one ten thousandth part of a second in duration.

Another film of the same subject then was passed through the projector
under conditions exactly similar except that the line dividing the
pictures in this case was black instead of white. When this picture
was thrown upon the screen, animation became apparent directly the
speed attained sixteen pictures per second, because after one image
had vanished from the screen it persisted in the brain, in spite of
the black flash, until the next picture appeared. Thus, the requisite
dissolving effect was obtained. The black flash did indeed produce a
defect like that which was common in the early days of cinematography
and was characterised generally as "flicker." But it did not suffice to
ruin the illusion of movement. A white flash destroys apparent motion,
owing to the brain being extremely sensitive to white: a black flash of
equal duration exercises no ill effects.

In the latest development of the art, one inventor has taken advantage
of this peculiarity. He has perfected a practical system wherewith the
shutter of the camera may be abandoned because each picture is cut off
from its neighbour by a very thin black line. An improved mechanism
jerks each picture off and brings the next one on the screen very
sharply, so that an effect is produced like that obtainable with the
shutter and without any impression of flicker. It may be pointed out
that with this invention there are none of the aberrations described in
a later chapter, such as the spokes of a wheel appearing to move in the
reverse direction to which the rim is travelling.

The next question is that of the speed at which it is necessary to
take and to project the pictures in order to get an apparently true
impression of natural movement. This factor to-day is governed almost
entirely by commercial considerations. It has been found, as a result
of elaborate investigation, that a speed of twelve to sixteen pictures
per second is the minimum wherewith in monochrome pictures animation is
obtainable. But this applies only to general work, such as records of
ordinary scenes, topical events and stage plays, where the action of
the moving objects is comparatively slow. In these instances an average
of sixteen pictures per second in photographing and projecting gives
completely satisfactory effects.

But in reality the speed is a variable quantity: it must be adapted
to the subject and the character of the work in hand. In other words,
strictly speaking, the speed must be accommodated to the velocity
of the subject so far as photographing is concerned, and also, in a
lesser degree, to the distance of the moving object from the lens. For
instance, when a man, walking four miles an hour, is photographed at
sixteen pictures per second, the movements recorded are far from being
natural or rhythmic. On the screen he appears to walk with a disjointed
action. To obtain a lifelike result, his pace should be slowed down
75 per cent., or the photographing speed should be accelerated to
seventy pictures per second at the least. This fact is illustrated very
conclusively in pictures of soldiers marching: they appear to advance
like automatons. Again, in photographing animals, a complete movement
is often lost between successive pictures. A cat in one picture will
be seen to the right; in the next picture it is on the left, having
sprung from one side to the other during the brief interval the lens
was closed. When extremely rapid movements have to be recorded, the
photographing speed has to be accelerated to an extreme degree, up
to ten thousand pictures or more per second in the case of a bullet
leaving the muzzle of a rifle, and up to two thousand pictures per
second to catch the movements of a dragonfly's wings. On the other
hand, in photographing very slow movements like the growth of a plant,
one picture per hour may be adequate.

In projection the speed can be adjusted. The ten thousand pictures per
second may be decelerated to sixteen per second to allow the movement
to be followed, and although the rifle bullet may appear to crawl
through the air, the movement is perfectly correct. Similarly the very
slow motions must be accelerated to sixteen pictures per second to
obtain evident animation. These two extreme phases of cinematographic
investigation are described at length in another part of this volume,
but are mentioned here merely to show that the photographing speed is
a somewhat elastic factor, to be adapted to circumstances in order to
produce passably natural effects.

For everyday work, however, a speed of sixteen pictures per second is
sufficient and represents the generally practised velocity. Possibly in
the near future the speed will be accelerated to twenty, twenty-two,
or twenty-four pictures per second, as the present speed is generally
admitted to be too slow. The eyes of the regular picture palace
patrons have become trained, as it were, with the result that there
is an appreciable strain of the eyes, while the disjointed character
of the movements on the screen may be detected. But when the taking
and projecting speed is accelerated by 50 per cent. the picture
stands steadier upon the screen, the movements are more natural,
and there is an entire absence of that automaton effect which is so
characteristic of most pictures taken under prevailing conditions.
These considerations do not affect photo-plays produced in the studio
so materially, because there the actions of the players can be slowed
down to suit the conditions.

One of the leading manufacturers is earnestly considering the
advisability of accelerating the taking and projecting speeds up
to about twenty pictures per second, and private investigations
and experiments have certainly demonstrated the value of such an
improvement. Unfortunately two difficulties prevent its immediate
realisation. An increase of only four pictures per second represents an
increase of 25 per cent. in the consumption of the film, and therefore
in its cost. The other difficulty is more serious. Existing apparatus,
both cameras and projectors, are geared to eight pictures per turn
of the handle. This involves two complete revolutions per second.
Consequently the gearing of the mechanism would have to be altered,
and this is a more troublesome question than appears at first sight.
Some time may elapse before a forward step is taken in this direction.
In matters of this character the cinematograph industry is notoriously
conservative, although the moment one firm courageously adopts an
accelerated speed, the higher quality of the resulting pictures will
force the others to follow the example.

As a matter of fact the decision to adopt sixteen pictures per second
was taken somewhat haphazardly without any scientific investigation.
When it became standardised, film was expensive. Accordingly, efforts
were made to secure the requisite effect with the minimum expenditure
of film. Machines were built to coincide with these requirements,
and the original designs have been followed slavishly in their broad
outlines ever since.




CHAPTER III

THE MOVING-PICTURE CAMERA AND ITS MECHANISM


The cinematograph camera differs entirely from the instruments used
in other branches of photography. While the advanced worker and
the prosperous picture-play producer employ costly and elaborate
machines, the amateur, or the independent worker, in the particular
field which he has selected for his operations, can get equally good
results with an apparatus only a fifteenth or even a twentieth part
as expensive. The range of operation with the cheaper instrument may
be limited, and it may be deficient in those many little refinements
which are characteristic of the professional appliance, and may lack
silver-plated finish and highly-polished woodwork or morocco leather
covering. But the camera itself is more important than these.

The cameras, both expensive and low-priced, work upon the same
fundamental principles. In the latter everything is reduced to the
simplest form so as to be readily and easily understood by the
beginner. They have the additional recommendation that the risk of
breakdown is eliminated, because the few essential component parts
are substantially made, well-proportioned, and nicely-balanced.
Serviceability and reliability are the outstanding features of the
low-priced camera, and it is applicable to almost every branch of the
craft.

Contrary to general belief, taking the "movies" is quite as simple as
snap-shot photography with a Kodak. In the latter case you press the
button; in the former you turn the handle; the camera does the rest.
The rotation of the handle, a simple operation, performs every duty
through the internal mechanism. It swings the shutter across the lens,
moves the film intermittently through the instrument, and coils up the
exposed film in its dark box.

As has been explained, the beginner is now able to make his selection
from a wide variety of makes, ranging in price from L5 ($25) upwards.
If one desires to gain experience in the cinematographic art with the
minimum capital outlay, the Jury, "New Era," or "Alpha" cameras will
suit the purpose excellently. Both are first-class, well-made machines,
having perfect registration and alignment, extremely simple and easy
to handle. The first-named model, which is the cheapest, is contained
in a mahogany case measuring 9-1/2 inches square by 4-3/4 inches deep,
and in the unloaded condition weighs 5-1/2 pounds. The "Alpha," which
costs a little more, is full value for money, and is well worth the
slightly increased price. This camera is fitted with a light-proof
hinged front panel giving access to the adjustable shutter, which
permits the opening of the latter to be varied within wide limits and
thus enables extremely rapid movements to be photographed while running
the machine at the normal speed. The spool boxes carry 100 feet of film
of standard gauge in each instance, and for general all-round work,
such as the recording of topical events, either model will be found
perfectly efficient. It may be mentioned that both models are supplied
without the lens, because the average beginner in motion-picture work,
having practised still-life or snap-shot photography, has usually
developed a marked fancy for some particular make of lens--Dallmeyer,
Cooke, Ross, Zeiss-Tessar, or Voigtlander. Naturally, being familiar
with the working of his favourite and knowing what he can do with
it, he feels more at home when he is able to have it fitted to his
moving-picture machine. Here, again, there is a wide selection to meet
all purses, so that the most fastidious tastes in regard to the lens
may be gratified. On the other hand, if the beginner has no marked
preference, and wishes to be economical, he can get a lens capable of
doing first-class work at a remarkably low price. His complete outlay
upon the camera and the lens need not exceed L6 5_s._, or, say, $31.

If prices are not to be so strictly considered, and if the beginner
wishes to have a machine of the finest type at a comparatively low
figure, he cannot do better than fit himself out with a Williamson
camera, the price of which, complete with lens, is L10 10_s._, say
$52. Except for an expert, it is difficult to detect the difference
between this machine and one which costs five times as much, for both
are designed upon the same lines, are equally well made, and equally
capable of doing the finest work. It must not be forgotten that Mr.
James Williamson, the designer of the latter instrument, was one of the
pioneers in cinematography, and, in his machine, the results of some
twenty-five years varied and accumulated experience are incorporated.
He has been able to realise just those essentials which are required
for a high-class apparatus free from complexity, and this end has been
achieved to excellent effect. The camera, finished in a brass-bound
mahogany or teak case--the latter is preferable for working in tropical
countries--measures 9-1/2 inches square by 4-3/4 inches deep, is fitted
with a Zeiss-Tessar 2-inch lens with focusing, and iris diaphragm.
It weighs 7-1/2 pounds complete in loaded condition. It is eminently
suited for all round duties, from the rush and tumble of topical work
to the uneventful, quiet but exacting requirements of the laboratory.

[Illustration: THE JURY MOVING-PICTURE CAMERA.

B. Driving sprocket. A, C. Upper sprocket pulleys. D. Exposure window.
H. Gate. E, F. Lower sprocket pulleys. G. Exposed film-box guide
pulley.]

[Illustration: THE WILLIAMSON TOPICAL CAMERA AND TRIPOD.

A. Camera. B. Handle. C. Lens. D. View finder. E. Tripod head. F.
Horizontal panoramic movement handle. G. Vertical panoramic movement
handle.]

These machines by no means exhaust the selection. Other manufacturers
have produced very good instruments at competitive prices, but those
which I have mentioned represent probably the best in their respective
classes. For the purpose of introduction to the art of cinematography
the beginner can do no better than obtain one of them. If, after a
little experience, he comes to the conclusion that he has ventured into
the wrong province, then his monetary expenditure is not serious.

It will be seen that the aspirant has no lack of inducement to embark
upon the moving-picture industry. Provided he has acquired a certain
knowledge of the elements of photography, and is possessed of average
intelligence, there is no reason why he should not be able to produce
pictures with his inexpensive machine that are in all ways comparable
with the product of the professional worker and the costly instrument.
Naturally, as the intricacies of the craft are mastered, the tyro will
wish for a more elaborate apparatus. He can gratify his ambitions in
accordance with his progress, or with the improvement in his financial
position.

The mechanism of the modern cinematograph camera is very simple in
its character and very easy to understand. The necessary parts are
very few in number. In all cameras the chief object is to effect
the forward intermittent movement of the film at regular intervals
and for a defined distance. For this purpose the early types of
camera were fitted with what is known as the Geneva stop movement.
Opinion is divided upon its merits, some authorities condemning it
unequivocally, while others uphold it strenuously, contending that it
gives a steadier and freer motion. There is much to be said in favour
of the latter view. Mechanically the Geneva stop movement is perfect.
So far as cinematography is concerned its advantages were proved most
emphatically by Mr. Robert Paul, the first man to bring motion pictures
into commercial application in Great Britain. He adopted this movement
in his camera, and it cannot be denied that his pictures were in every
way equal to those produced to-day, while his camera has never been
excelled. Curiously enough, although this movement has been superseded,
there is a tendency among expert workers to revive it, and many cameras
specially built have been fitted with it.

The movement more commonly used is that known as the "claw." It is
simple, and has the advantage of bringing the film into place for an
exposure with a sharp, quick jerk. But it is a movement which requires
to be designed very finely in order to perform its work smoothly and
evenly, and without inflicting any injury upon the film.

The claw consists of a small lever in duplicate, which is so mounted
as to have an eccentric movement and is driven direct by the main gear
wheel rotated by the handle. The free upper end of each arm of the
lever has a projecting pointed tooth of sufficient size to engage with
the perforations on either side of the film. With the revolution of the
wheel upon which it is mounted eccentrically the claw engages with the
perforations, and, thus gripping the film after the manner of a ratchet
and pawl, jerks it downwards a definite distance. When this downward
movement is completed the claw disengages from the perforations and
falls back clear of the film. Then the wheel, continuing its rotary
movement, proceeds to lift the claw. When it has raised it to its
highest point it brings it forward smartly to re-engage with the
perforations, and causes a fresh downward movement of the film.
The action is intermittent and occurs at regular intervals, while
the movement of the film is always the same. Quick engagement and
disengagement of the perforations is imperative for preventing the
vibration and tearing of the film.

[Illustration: Fig. 1.--Mechanism of camera showing threading
of film.]

The mechanism of the camera may be understood from the diagram (Fig.
1), which refers to the Williamson instrument. The sprocket A is driven
directly by the operating handle, which engages with the sprocket
spindle. This sprocket A is fitted with two rows of teeth, mounted
upon its periphery, and so spaced apart, both circumferentially
and transversely, as to coincide with the distances between the
perforations of the film. A pair of twin rollers, D and E, bear against
this sprocket under the tension of a spring, their object being to
keep the film pressed firmly against the sprocket. The teeth engage
with the film perforations, so that by the rotation of the handle and
sprocket the film is fed forwards regularly, smoothly and evenly, as it
is drawn from the loaded spool box B.

The film is brought into position before the lens by passing through
what is known as the "gate." This device H consists of two parts of
which the first is fixed irremovably while the second is hinged to the
first at one side and kept flat against it by means of a spring. Both
of the parts are provided with an aperture or window, the exact size of
a cinematograph picture--1 inch wide by 3/4-inch deep--through which
the light passes, after admission through the lens, to strike upon the
sensitized surface of the film. There is just sufficient space between
the two parts of the gate to permit the film to move easily, and its
object is to hold the film perfectly flat and steady during the period
of exposure. Each picture is thus kept in absolute focus.

The feed through the gate is accomplished by the claw N, which is
mounted upon the eccentric O as already described. At the instant of
exposure the claw is free of the film, or in the "out position," as it
is termed, so that the sensitized ribbon is absolutely still. When an
exposure has been made, the claw, having risen to the highest point
of its travel, re-engages with the film and jerks it down 3/4 inch,
so as to bring a fresh unexposed surface before the lens. As the film
emerges from the gate it is picked up once more by the sprocket A, the
engagement of the perforations in the film with the sprocket teeth
being assured by the two rollers J and K. The film then passes under
the guide roller L, and is wound up on the bobbin M in the exposed
film box C, the bobbin being worked through the handle that drives the
mechanism.

The rotation of the handle also ensures, through gearing, the
revolution of the shutter P, whereby the lens is eclipsed
intermittently. The shutter is a ring fitted with an opaque sector
which comes before the lens and shuts out the light during the movement
of the film through the gate H by the claw N. In the Williamson camera
this shutter is recessed into the case.

Although the lens may be of the fixed focus class--the focussing
distance varying with the stop used--focussing can be carried out
independently if very critical work is required. In the case of the
Williamson camera and others of this type, focussing is accomplished
by opening the shutter and the side of the camera and looking through
the gate. In some cameras a focussing tube is provided. This passes
from the gate to the rear of the instrument, through a space provided
between the superimposed film dark-boxes. It is telescopic at the
forward end. Thus, when focussing is being carried out, it can be
extended so as to come flush with the gate, and pushed back out of the
way when all is ready for working, so that the free movement of the
film is not obstructed in any way. The rear end of the tube, which
extends through the rear face of the camera box, is fitted with a cap
to save the film from being fogged by light entering from behind.

One conspicuous advantage of the Williamson machine is that the whole
of the mechanism is mounted upon a skeleton casting fixed to the
interior of the mahogany case by means of four screws. By withdrawing
these the whole of the internal mechanism may be removed intact, and
much trouble is saved when inspection or repairs are necessary.

In some cameras the intermittent movement of the film is effected by a
single claw which engages with the perforations upon one side of the
film only. But this movement is not perfect. All the pulling strain
is thrown upon one side of the film. This gives it a tendency to move
unevenly into the gate and also increases the risk of tearing.

The driving gear of the camera is so adjusted that one complete
revolution of the handle completes eight exposures. Consequently two
revolutions have to be made per second to maintain the necessary speed
of sixteen pictures per second. In the Williamson camera this is
emphasised as a fixed speed in ordinary working, and any compensations
demanded by the varying intensity of the light are made by altering the
aperture of the lens. This is a logical method, for if the operator is
required to make such compensations by varying the speed of his handle
he is apt to obtain an indifferent result. It requires a very skilled
operator indeed to vary the speed of the handle with judgment between
the narrow limits possible. In some cameras this compensation for light
is effected by varying the area of the opaque section of the shutter,
but this is not so simple or effective a method as the variation of the
stop. The latter can be accomplished while the camera is being driven,
but in the former it is necessary that the work should be stopped while
the front panel camera is opened and the shutter adjusted.

As for the tripod, one cannot be too careful in choosing it. This
apparently insignificant detail has a far-reaching effect upon the
picture results. Any ordinary tripod used in photographic work may
suffice, but its absolute rigidity is essential. A tight head, too, is
most necessary, without which the operator will get a side-to-side
sway upon the picture. It must be borne in mind that in turning the
handle there is a tendency, especially at first, to exert an unequal
pressure upon the handle side of the camera, and, unless the support
and its head are kept absolutely rigid, the pictures will betray
evidences of the defect. The telescopic ladder tripod is very handy for
topical work. This, when it is extended and when the camera is fixed,
brings the lens some 7 feet above the ground. A cross-rail placed from
12 to 25 inches above the ground, and attached to the rear legs, offers
a platform upon which the operator can stand to work his instrument. In
this way both camera and operator are brought above the heads of the
crowd, and an uninterrupted view can be obtained.

For moving-picture work a special type of tripod head has been evolved,
which allows the camera to be moved bodily through both the horizontal
and the vertical planes while exposures are being made. Thus it
can follow a subject travelling in either of these directions. The
movements are upon the rack and pinion principle, a small handle being
fitted to each motion so that either can be operated independently of
the other. By means of this panoramic attachment the main object in the
picture, such as a carriage or an aeroplane, may be followed in either
direction. But if both movements are to be completed simultaneously,
the operator will require help. One person must sight the object and
keep it in the picture by the manipulation of the two handles governing
the respective movements of the tripod head, while the other confines
his energies to turning the camera handle.

Although the moving-picture camera is built substantially and strongly,
its mechanism is comparatively delicate. While it will withstand the
hardest descriptions of legitimate work, it succumbs readily to brutal
treatment. Although operated by means of a handle, it is neither a
coffee mill nor a barrel organ, but a sensitive scientific instrument,
and it must be treated as such if the finest results are to be
obtained. Rough usage will throw out the registration and alignment. If
handled carefully a camera should perform its task for years without
needing repair. The effects of wear and tear can be mitigated very
appreciably by keeping the moving parts well lubricated with good oil,
such as is used for clocks, which neither gums nor clogs the bearings,
nor injures the mechanism in any way.




CHAPTER IV

THE CAMERA AND HOW TO USE IT


Having examined the mechanism of the moving-picture camera, and the
broad principles upon which it works, we must now study the way to use
it.

The first step is to load the film box, an operation which must
be carried out in the dark room. The film is sold as a rule in
standardised lengths, such as 100, 200, 350 feet, etc. With the
ordinary type of camera the 100 or 200 feet lengths are used. For
topical work either are quite adequate as a rule.

As has been said, the film is supplied perforated and ready for use.
Many firms that sell the "stock," as the unexposed film is called,
attach a blank or unsensitized "lead" to one end of the roll, for the
purpose of "threading-up" the camera. If this is not supplied, and if
the operator wishes to avoid the waste of 2 or 3 feet of sensitized
ribbon, the deficiency can easily be remedied. For the blank "lead"
all that is required is about 3 feet of useless or spoiled film which,
however, should not be torn or cracked. The emulsion at one end of
this should be scraped off for a distance of about 1/4 inch. A pocket
knife will do this very efficiently. The blank should then be laid
flat upon the table, emulsion side uppermost, preferably upon a sheet
of glass which secures a smooth, clean, level surface, and a little
film cement applied to the scraped end of the blank. Film cement can
be obtained readily and cheaply in small bottles complete with cap and
brush. A bottle should always be kept to hand as it is often required,
especially in joining up successive lengths of film; but if it should
so happen that none is available at the moment, glacial acetic acid
may be used with equal success, although it demands more careful
handling. In an emergency alcohol constitutes a first-class cement,
but it requires extreme care and skill because it is a solvent of the
celluloid base.

After the cement has been applied to the cleaned end of the blank lead,
the end of the unexposed coil of film is laid upon it, emulsion side
uppermost, the overlap being about 3/4 inch. Care must be exercised to
see that the joint is made perfectly square and that the perforation
holes of each piece of film come dead true, otherwise there will be
trouble in passing the joint through the camera mechanism. When it has
been superimposed satisfactorily, pressure must be applied to secure
perfect adhesion. In order to ensure perfect jointing a film jointer
should be used: in fact it is an indispensable and inexpensive tool.

When attaching the blank lead every precaution must be taken to protect
the spool of unexposed film from light; only a very faint ruby glow
should be used, for the cinematograph film is extremely sensitive.
The cement dries rapidly, and the joint being found to be perfect the
dark box should then be loaded. The coil of ribbon is slipped over the
central bobbin. A hole large enough for this purpose is always left in
the coil. The end of the lead is then passed through the velvet-faced
slot near the bottom of the box. In order to prevent the loose end
slipping back into the box, in which event there must be another
journey to the dark room, it should be bent back and re-entered into
the slot so as to form an external loop. The dark box is then closed,
and securely locked, and is ready for insertion in the camera. It is
advisable to carry at least two loaded boxes, especially if each is
only of 100 or 200 feet capacity. The camera is provided with two dark
boxes, one placed above the other. The upper box carries the unexposed
film, while the lower receives the ribbon after exposure.

The camera may then be "threaded-up," or, if focussing is desired,
this can be completed first. With the Williamson camera focussing
is unnecessary within certain distances owing to the fixed foci of
the stops. These will be explained later. Many other manufacturers
of cameras follow the same principle, and it is most convenient for
every-day work. Yet it may happen that the operator desires to focus
critically. In this event he opens the side of the camera, lifts the
pressure plate of the gate, and inserts into the gate window a small
length, about 2 inches, of matt film, with the matt side towards the
lens. The matt film serves exactly the same purpose as the ground-glass
in the ordinary plate camera. The handle is revolved until the lens is
opened, and the image thrown upon the matt film becomes apparent. This
can then be focussed by moving the milled focussing screw on the lens
until the picture stands out as sharply as is desired. At first the
operation may appear to be somewhat awkward, because the operator has
to look upon the matt film at an angle. It is easier in the case of a
camera fitted with a focussing tube, for the operator has then merely
to open the side of the machine to insert the matt film and push the
telescopic tube out to its fullest extent to bear against the gate.
By removing the cap from the tube upon the rear face of the camera,
and looking through it as if through a telescope, he is able to look
squarely upon his screen.

When focussing is complete the matt film is withdrawn and placed in
a safe position. It is a good plan to clinch it to the bottom inner
surface of the camera with drawing pins, for it can then be found when
it is wanted. Should the piece be lost the defect can be repaired
as follows. Take a small bit of waste film; scrape off the gelatine
emulsion; and rough the celluloid surface with a piece of sandpaper; or
even with a rough stone surface. It is well to carry a few inches of
spoiled film in the pocket for such an emergency.

The film may now be threaded up. The loop of blank projecting from the
dark box is picked up and the coil within is steadily unwound as the
threading proceeds. The blank is first passed under the pressure roller
(marked D in Fig. I), and then under the spring roller E, which can be
lifted for this purpose. It must be seen that the teeth of the sprocket
engage with the perforations in the film. A loop G is then made and
the film is threaded through the gate H. Before this can be done the
claw N must be thrown in the "out" position to obtain access to the
gate, which is done by turning round the eccentric. The spring part
of the gate is then opened on its hinge, and the film is slipped in
from the side. Care must be observed that an ample loop is left above
the gate. When the gate is closed once more another loop I similar to
that above the gate, is formed. The film now is passed round the under
side of the sprocket A, the spring roller J being pressed back to admit
of easy entrance, and the end of the blank is passed under the second
or pressure roller K. Here again one must be careful to see that the
insertion is square and that the sprocket teeth mesh with the film
perforations. The film is then carried under guide roller L and through
the velvet-faced slit into the empty film box C. This must be opened
to permit the free end of the lead to be secured to the centre bobbin
M, on which the film is wound in after exposure. The handle should be
given a few turns to see that threading has been carried out properly,
and also that it is properly attached to the bobbin M. If a sufficient
length of blank is attached to the end of the unexposed film, and a
piece of gummed paper is fixed on the lead about 6 inches in advance of
the joint, it is possible to continue winding in on the lower bobbin
until this mark appears at the mouth of the loaded dark box.

If the threading has been accomplished properly the interior of the
camera should be as shown in the illustration facing p. 42. Here both
film boxes are shown open, though of course the upper one is kept
closed during the threading process. The most important part of this
operation is the formation of ample loops both above and below the
gate. Once formed they remain constant, because of the action of the
teeth on the sprocket; for the movement of the ribbon over the sprocket
is equal to that produced by the claws through the gate. At first
sight the necessity of these loops may not be apparent, but when it
is remembered that the film is moved through the gate intermittently,
sixteen times per second, with a vicious jerk, it will be seen that if
there were no loop, and the film were drawn directly from the dark box,
a great strain would be imposed upon it, and probably it would break.
But by providing the loop an elastic feed is secured, and the film is
jerked into position before the lens with the minimum of vibration and
without any risk of tearing or displacement.

Threading completed the lower dark box is closed and secured, together
with the side of the camera, so that the whole of the interior is
light-proof. The camera should not be re-opened after photographing has
commenced until the whole of the film in the loaded box is exhausted,
or, if the supply is not used, until the dark-room is regained, unless
the waste of a foot or two of film is a secondary consideration.
Should it become necessary to open the camera in the field, the handle
should be given two or three turns to make sure that the last picture
taken is wound into the exposed film box and is thus secure from the
light. Opening the side of the camera obviously ruins the whole of the
unexposed film threaded through the mechanism, so that when picture
taking is resumed the handle must be given a few more turns to make
sure that the whole of the light-ruined film has passed through the
gate. Seeing that one turn of the handle represents eight exposures,
equivalent to 6 inches of film, it is a simple matter to estimate how
many turns of the handle are necessary to clear the gate of spoiled
film.

Most cameras are provided with a film indicator enabling the operator
to tell at a glance how many feet of film have been exposed. In this
case, care must be taken to see that the indicator is returned to zero
when the mechanism is threaded-up.

Another convenience is the "punch" whereby it is possible to mark the
film after an incident has been photographed, so that the worker can
afterwards tell in the dark room by a mere touch where the exposure
ended in each case. The film should be marked after every episode
is finished because it is then possible, if desired, to develop the
film in lengths. Indeed it is advisable to follow this practice, and
especially when the exposures have been made under varying conditions
of light. By developing in sections one gets lengths of uniform
density--a great assistance in printing.

[Illustration: THE WILLIAMSON CAMERA THREADED READY FOR USE.

The film is taken from the upper unexposed film-box, passed over the
sprocket, through the gate, under the sprocket and wound into the lower
exposed film-box.]

[Illustration: THE LENS OF THE WILLIAMSON CAMERA.

(For explanation see p. 43.)]

[Illustration: THE ADJUSTABLE SHUTTER OF THE JURY CAMERA.]

In cinematography, as in ordinary photography, the judgment of
the brilliance of the light and of the right stop to use on each
occasion, is the one important factor for which mechanical provision
is impossible. This is because of the extreme variation of the light
conditions. But, while no hard and fast rules concerning exposure can
be laid down, it is possible to give the beginner a little guidance
to keep him on the safe side. Practice alone can make perfect, and
experience is the more necessary because the cinematograph is an
all-the-year-round machine. In topical work the operator is compelled
to make the most of the existing weather conditions, no matter how
deplorable they may be.

Under these circumstances it is well to have what might be termed a
very flexible lens. The lens, that is to say, should be fitted with
the means of varying the size of the aperture, and varying it within
wide limits, according to the light conditions. The simplest way of
achieving this is by means of what is called an iris diaphragm.

To illustrate the functions of the iris diaphragm we will take the
Williamson instrument. This is fitted with a Zeiss-Tessar lens of
2-inch focus. By the aid of the iris diaphragm the diameter of the
aperture may be varied from approximately 3/5 to 1/8 of an inch. Now
it is obvious that more light can be passed through the lens with the
larger, than with the smaller, aperture. While the larger aperture
would do excellently for filming a football match on a dull day in
mid-winter, it would be useless for a seascape on a cloudless day in
July. For the latter the smallest aperture would suffice. But the
requirements between these two extremes must be met: in other words the
aperture must be adapted to intermediate demands. By turning the milled
ring in which the iris diaphragm is mounted the size of the aperture
can be varied even to a minute degree and thus adjusted to any sort of
light conditions. For the guidance of the operator the total rotary
travel of the ring is graduated to six different definite points or as
many different sized apertures. These are as follows:--

  _f_/3.5 gives an aperture 3/5-inch in diameter (nearly)
       4    "         "     1/2-inch         "
      5.6   "         "     1/3-inch         "       "
       8    "         "     1/4-inch         "
      11    "         "     1/5-inch         "       "
      16    "         "     1/8-inch         "

Although the differences between these successive apertures are very
slight, they exercise a very appreciable effect upon the volume of
light passing through the lens, and accordingly the period of the
exposure. Thus although stop _f_/5.6 only decreases the size of the
aperture by 1/6 of an inch over _f_/4, yet the effect of this reduction
is to necessitate twice as long an exposure as is suited for the latter
stop. Similarly _f_/8 demands twice the exposure of that required for
_f_/5.6, and so on, the exposure being doubled with every diminution
of the stop up to the limits of the diaphragm. Yet in practice this
increase of exposure between two stops is impossible, because the
handle must be turned at a definite speed. It is obvious, therefore,
that compensation must come from another quarter. Instead of increasing
the duration of the exposure we must have a greater intensity of light
for _f_/5.6 than for _f_/4.

At first sight the beginner might be disposed to think that the
selection of the most favourable aperture is a matter demanding
extremely fine judgment and skill, especially when there are other
factors which may upset calculations. Many other advantages arise from
using as small an aperture as possible, such as increased sharpness of
the picture, especially at the edges. Mr. Williamson the designer of
the camera has realised this, and as a result of his unique experience,
he has set down some very useful rules to guide the beginner, as to
which stop should be used for varying conditions of light and subject.
In elaborating this advice Mr. Williamson rightly commences from the
zero point as it were, taking moving-pictures of a football match on a
dull winter afternoon, when, owing to the feeble light, the capacity of
the lens and the sensitiveness of the film are strained to the utmost.
From this point he has graduated the diaphragm and its use as follows:--

  --------------------------------------------------
    Stop.   |       Subject and Conditions.
  --------------------------------------------------
    F/3.5   | On a dull winter's day; well-lighted
            | interior: or on a subject at any time
            | of the year where there are heavy
            | shadows such as under trees.
  --------------------------------------------------
    F/4     | On a bright day in winter: on dull
            | days in spring and autumn.
  --------------------------------------------------
    F/5.6   | Outdoor exposures during September,
            | October, March, and April. Dull
            | summer weather.
  --------------------------------------------------
    F/8     | Street scenes in bright summer
            | weather.
  --------------------------------------------------
    F/11    | Open fields in bright sunshine.
  --------------------------------------------------
    F/16    | Bright sea and sky subjects.
  --------------------------------------------------

It must be understood that the foregoing are not set down as hard and
fast guiding rules, but they may be safely taken as some indication of
what should be done under such varying conditions. They may be said to
apply generally to the temperate zones where the conditions are almost
identical, irrespective of geographical situation. If the beginner
follows them at first he will not make very serious mistakes. But, as
has been said, experience alone can finally determine the factor of
lens aperture.

The size of the aperture has another far-reaching effect. This is
in regard to focussing. With the 2-inch Zeiss-Tessar lens of the
Williamson camera when the largest aperture is used, nothing important
in the picture should be within a distance of 20 feet. If it is,
it will not be in focus. As the diaphragm is closed this distance
decreases proportionately until the infinity, INF, mark is reached. At
this point practically everything is in focus. The distance when other
objects are in focus at the respective stops is as follows.

  _f_/3.5  focus distance   20 feet
  _f_/4      "      "       20  "
  _f_/5.6    "      "       15  "
  _f_/8      "      "       12  "
  _f_/11     "      "       10  "
  _f_/16     "      "        5  "
  INF        "      "        everything.

At first sight the fact that the camera is operated by the turning of
a handle makes it seem to be absurdly simple. One or two experiments
however, will prove that it is far from being as easy as it looks.
The salient point is to turn the handle steadily and evenly so as to
complete two revolutions per second. The first pictures will be found
to be very unsatisfactory, having an eccentric jerky effect instead of
a smooth easy animation. An even pressure must be maintained throughout
the complete rotation, and, before the beginner attempts to take any
pictures and thereby waste expensive film, he would do well to practise
handle-turning until he has become proficient. If the turning movement
is timed with a watch, and "one" corresponding to a second is counted
for each double turn, a perfectly steady turning movement will soon be
attained. Some cameras are fitted with an indicator which records the
number of feet of film consumed. But no anxiety need be felt if this
convenience is absent. The operator need only count one, two, three,
and so on, while turning the handle, each number representing a double
turn. In this way, as 16 pictures, equivalent to one foot of film, are
made with every double turn and every one count, the number reached at
the end of the task will show how many feet of ribbon have been used,
and if this is deducted from the amount originally held by the loaded
box it is easy to tell the length of film unused. When the upper box
has been exhausted and the lower box filled, the latter is withdrawn
and packed away to be opened in the dark room only. The empty upper box
is taken out and slipped into the lower position to act as a receiver
from the next loaded film-box.

In photographing, the operator must keep his eyes riveted upon the
view finder, to make sure that the subject he desires is in the field
of the lens. The movements can be followed easily, and there should be
no difficulty in keeping the most important part of the subject in the
centre of the picture.

To follow the subject either in a horizontal or vertical plane it is
necessary to turn the handle controlling the panoramic movements of the
tripod head. This mechanism should be turned slowly and steadily with
one hand, while the other is turning the camera handle. It is by no
means an easy, simple matter to follow a subject in this way without
any disconcerting jerky movement, since it involves doing two things
at once. For a beginner it is particularly exacting, as an eye must
be kept fixed upon the view finder to follow the moving object. But
after a little experience the whole of these movements are carried out
in a semi-mechanical manner. In cinematography, it is the diligent,
careful, and persevering worker who scores successes. In the beginning
failures may be galling and frequent, but practice and experience are
the best teachers. One can soon become adept in a fascinating art.




CHAPTER V

HAND CAMERA CINEMATOGRAPHY


During the past few years competition among professional moving-picture
photographers has become exceedingly keen, especially in connection
with the filming of topical events. The operator often is faced with
prodigious obstacles, the subjugation of which is not always easy,
or even possible. For instance, in a dense crowd the conventional
apparatus, from its bulkiness, weight, and proportions, cannot be
handled, and, even if set upon its tripod with the lens elevated above
the heads of the people, there is the serious danger of the whole being
upset by the swaying motion of the mass of spectators. Yet at the same
time a place in the crowd constitutes an ideal point of view.

Again, there are many situations where the use of a tripod is
impracticable, if not dangerous. Take the aeroplane. An operator
seated in a flying machine and desirous of recording the moving scenes
beneath, cannot support his machine upon the conventional device for
this purpose. He has to hold it as best he can, and so secure his
pictures under extremely trying conditions. Although films innumerable
are taken by persons seated in aeroplanes, only a very small proportion
ever come before the public eye, for the majority are failures.
Nowadays, also, the filming of aeroplane flights from a fixed point on
the ground is by no means easy. In order to follow the evolutions of
flying machines, more particularly at comparatively close ranges and
when travelling at high speeds, two operators are required, one to turn
the camera handle, and the other to sight and follow the object both
through its horizontal and vertical planes in such a way as to keep
it in the centre of the picture. To do this he has simultaneously to
turn the two handles operating the panoramic and elevating gear of the
tripod head, and often in opposite directions. The task must be done
without the slightest jerk, or the success of the film is marred. One
of the most disconcerting effects upon the screen is a jumpy panoramic
movement either horizontally or up and down. It worries the eye, and
more often than not reduces the picture to an almost unintelligible
blur.

[Illustration: THE "AEROSCOPE" MOVING-PICTURE HAND CAMERA.

A. Air valve. B. Button for varying photographing speed during
exposure. C. Exposure button.]

[Illustration: THE COMPRESSED AIR RESERVOIRS OF THE "AEROSCOPE"
CAMERA.

One charge is sufficient to expose 600 feet of film.]

But perhaps the most unnerving and difficult conditions under which
moving-pictures can be taken are those pertaining to the filming of
wild animal life at close range under natural conditions. In this
case a good nerve, a steady hand, and acute presence of mind, are
indispensable. A wild elephant trumpeting madly and dashing towards the
camera at full speed, or a lion springing towards the operator may form
the subject for a thrilling incident in a film, but does not inspire
confidence in the cinematographer. Under such conditions a tripod
outfit is worse than useless. It not only endangers the operator's
life, but the pictures taken under such conditions are invariably of
poor quality, even if they survive the results of the animal's mad
frenzy. To stand one's ground and to keep turning the camera handle
steadily at two revolutions per second up to the last moment with
the _sang-froid_ of someone filming a street procession would put
too great a strain on human nature. Even the coolest man would not
obtain first-class results at uncomfortably close quarters. Instead of
turning the handle in a steady rhythmic manner the motion would be in
a series of erratic jerks, some fast and some slow, producing a result
which the public would ridicule. Mr. Cherry Kearton, whose pictures of
jungle life constitute some of the marvels of the cinematographic art,
considers that this branch of cinematography cannot be excelled for
thrilling excitement. The operator must stand his ground undismayed,
because the close-quarter pictures are always the most fascinating.
Yet at the same time he must keep a corner of one eye fixed upon an
avenue of retreat, so that he can get clear in the nick of time when
the crisis arises. The attention given to the photographic work must be
reduced to the absolute minimum, so as to be practically automatic; the
camera must be as small and as compact as possible, for the only way of
escape lies often up a tree.

Several inventors have devoted their energies to the evolution of
a reliable hand-camera, capable of fulfilling the same duty in
cinematography as the snap-shot instrument in still-life work. The
tripod was sacrificed, but then there arose another difficulty. This
was in the necessity of moving the film mechanism by means of the
handle. In fact, under many conditions of working, such as in the
jungle, it would be quite impracticable. What was required was an
efficient moving-picture machine, small, light, and compact, working
upon the principle of "you-press-the-button-and-I'll-do-the-rest."

It is a perplexing problem to solve, and the first commercially
practicable idea in this direction was conceived by the Polish
scientist Kasimir de Proszynski. He has produced a camera completely
self-contained and wholly automatic in its operation. Dimensions and
weight have been kept down. In loaded condition, with 300 feet of
film, it is 12 inches long, 8-1/2 inches wide, 6-1/2 inches deep, and
weighs only 14 pounds. It works upon the "press-the-button" system, the
film-moving mechanism and shutter running the whole time the button is
depressed. The power comes from cylinders of compressed air by which
a tiny engine is driven. All that the operator has to do is to sight
his subject and to keep his finger on the button, while he follows the
object on the view finder.

When this camera, known as the "aeroscope," appeared upon the market,
it aroused considerable interest, but its reliability was doubted.
It was not until Mr. Cherry Kearton decided to give it a trial that
it came to be regarded more seriously as a feasible moving-picture
machine. This naturalist-cinematographer took it with him on one of
his expeditions, and was able to record some startling incidents which
would not have been possible otherwise. Familiarity with the camera and
experience in the field convinced him of its serviceability, provided
that certain modifications were effected. These were carried out, and
the camera is now regarded as an excellent instrument for work that
could not be achieved by any other machine.

It is fitted, as has been said, with a small engine driven by
compressed air. The air is stored in six small cylinders of an
aggregate capacity of 600 feet. This is sufficient to expose 600
feet of film. The cylinders are charged with air in the manner of a
motor tyre and with a similar kind of pump. An indicator on the side
shows constantly the air pressure remaining in the reservoirs, while a
regulator enables the speed to be varied. The driving mechanism is very
light, small, and compact, and contains but a small number of parts, so
that the risk of failure is not great. Though it constitutes the most
delicate part of the whole mechanism, and requires careful handling, it
works remarkably well so long as it is kept clean and well lubricated.

Another prominent feature of the mechanism is what is termed an
equilibrator. Practically speaking this is a small gyroscope, and is
introduced to subdue any small vibrations or tremblings which arise
while the instrument is working. This part of the mechanism has been
criticized on the ground that a gyroscope, to be effective, must be
of appreciable weight. Many operators dispute the necessity for its
introduction. They point out that the beneficial effects are not
proportionate to the extra weight involved. Furthermore, being an
additional piece of mechanism, it enhances the risk of derangement.
Against these contentions, however, the operators who have worked the
instrument maintain that it nullifies all the vibrations set up by the
driving mechanism, which, though apparently slight, would otherwise
suffice to spoil the pictures. Seeing that the sole object of employing
this camera is the elimination of a rigid support such as a tripod,
it certainly seems worth while, even at the cost of added weight, to
gain some compensating steadiness. And the vibration of the air engine
increases the need.

[Illustration: THE LENS, SHUTTER, COMPRESSED AIR-DRIVEN
MECHANISM, AND GYROSCOPE, WHICH COUNTERACTS SLIGHT VIBRATIONS, OF THE
"AEROSCOPE."]

[Illustration: LOADING THE "AEROSCOPE" CAMERA.

The unexposed and exposed film-boxes are mounted upon one spindle.]

In operating this instrument the usual method is to hold the camera
against the chest and one cheek, thereby bringing the eye on a level
with the sighting piece. By letting the elbows rest against the body
the weight is easily and steadily supported. Held in this position the
minimum of fatigue is felt by the cinematographer, while he is given
complete control over the mechanism. It can also be used when the
operator is on horseback, the method of support being virtually the
same. But in this case only one hand is used; the other is left free
to control the horse. Another advantage of the system is the ease with
which the camera can be swung round in order to follow a moving object
steadily.

Photographers who use a hand-camera are familiar with the disturbances
set up by the motion of the body in breathing. This is often sufficient
to spoil a picture if care is not displayed at the instant of exposure.
With the aeroscope--owing to the exposure being from 1/32 to 1/50 of
a second, relatively long in comparison with snap-shotting where the
exposure is often only the 1/200, or even less, of a second--these
disturbances are somewhat more acute. Considerable practice is required
before this difficulty can be overcome. Some operators who have used
the aeroscope prefer to utilise a convenient support, if available,
such as a wall, or the stump of a tree, thereby making sure of a solid
rigid foundation. But in cinematography the ill-effects arising from
respiration are not so serious as in still-life work. A picture here
and there may show its effects, but they pass unnoticed. They are
subdued, as it were, by the unblemished pictures which precede and
follow.

Another camera of this type is the "Jury Autocam" which, as its name
implies, works upon the automatic "press-the-button" system. This
camera is fitted with a small electric motor, driven by a small dry
battery, and brought into action by the pressure of a button. A small
side-lever controls the picture-taking speed, which can be varied while
the mechanism is running. The camera itself is exactly similar to the
"Jury Duplex" model, the only addition being a small separate case,
about 2 inches in depth, fitted to the base of the instrument, and a
covered chain gearing on one side for transmitting the power from the
motor to the camera mechanism. This camera likewise is fitted with a
small balancing apparatus to counteract slight vibrations.

[Illustration: Mr. Cherry Kearton steadying himself upon a precipice to
take pictures of bird life.

Mr. Cherry Kearton slung over a cliff, showing the operation of the
hand camera.

THE "AEROSCOPE" CAMERA IN THE FIELD.]

[Illustration:

 _From the "Cinema College," by permission of the Motograph Co._

VULTURE PREPARING TO FLY.]

In such instruments as these the even running of the motor is a vital
factor. It must not run any faster when the reservoir or battery is
fully charged than when it is nearly exhausted, nor must there be
any variations of speed, for eccentricities of this sort are apt to
spoil the film. The governing therefore requires to be most delicate
and thorough. Another difficulty is the incorporation of a reservoir
capable of carrying a sufficient quantity of air at the necessary
pressure to drive the length of film for which it is rated. In the
"Jury Autocam" a length of 100 feet can be driven on a single battery
charge. This is adequate for many purposes, but a length of at least
200 feet is generally to be preferred. The camera is being adapted to
meet these conditions, and it is anticipated that no more difficulty
will be met in consummating this end, than was involved in making the
camera drive a 100 feet length.

While it is a moot point whether the automatic cinematograph camera
will ever displace the orthodox machine entirely, it is a useful and
even indispensable machine for working under difficulties. It has been
used in the aeroplane and has been found successful. It is also of the
utmost use in close-range dangerous work, or in situations where the
turning of the handle by hand is liable to be carried out imperfectly
and unsteadily. The aeroscope camera has been used on many notable
expeditions such as those of Paul Rainey, and others in Africa, and
is used exclusively by Mr. Cherry Kearton in his daring work in tight
corners. Many of the thrilling and exciting pictures taken in the
haunts of wild animals have been secured therewith, and these films
show convincingly what can be done with the instrument when it is
handled by an expert.

But the true province of the hand cinematograph camera undoubtedly is
in connection with rush work. For the filming of topical incidents it
is invaluable. The operator is not trammelled with a bulky outfit. He
carries his camera in his hand or slings it across his back in the
manner of a knapsack. When he wishes to film an incident he is not
harassed even by the crowd. He is not compelled to set up a tripod or
to climb to an elevated point to get clear of the sea of heads. He can
hold the camera above his head, and by means of a second and special
view finder placed on the under side of the instrument he can sight
and follow the subject while pressing the button. Thus he records the
episode as easily as if he were placed in the most advantageous raised
position, and could manipulate the machine in the orthodox manner. When
his work is completed he can get away without any delay, because the
small box contains everything.

On the whole, however, the hand moving-picture camera is scarcely yet a
suitable instrument for beginners. The invention is in its infancy, and
although clever men are striving to make it more simple and reliable,
many peculiar problems still remain to be solved. But in the hands of
an expert operator it is capable of doing first-class work.




CHAPTER VI

DEVELOPING THE FILM


The beginner, when he handles for the first time a coil of sensitized
film measuring 1-3/8 inches in width, and perhaps 200 feet in length,
might hesitate to attempt its development. He might prefer to despatch
it to a firm prepared to carry out this work for a light charge,
confident that with the facilities at their command, and with their
accumulated experience, they would be able to bring out his work to the
best advantage.

But the man who aspires to succeed in topical work for the local
picture palace or general market, especially if he is not within easy
reach of a post office, must be prepared to undertake the task himself.
As a matter of fact it is by no means so difficult as it appears at
first sight, and the rudiments of the process may be grasped readily
by a person of average intelligence. Success, as in other handicrafts,
only can be achieved with practice.

Cinematography, being a peculiar and special branch of the photographic
art, demanding the use of new and unfamiliar tools, has been
responsible for the perfection of particular devices and methods to
assist and facilitate development. In the early days the worker had
to worry through the task, and was compelled to undertake a host of
doubtful experiments. The beginner of to-day is able to profit from
the mistakes of the pioneers, and the appliances and processes at his
disposal are those of approved application. After one or two trials
the worker will realise that the development of a 200-feet length
of celluloid ribbon is no more difficult than the development of an
ordinary Kodak spool.

One thing the beginner will do well to bear in mind. He should adopt
some particular brand of film, and cling to it after he has become
acquainted with its emulsion, speed, composition, and peculiar
characteristics. There are three or four different makes of film upon
the market, but it is preferable to select a film which is easily
obtainable at any time and in any part of the world. I would strongly
urge the beginner to select the Eastman stock for this if for no other
reason. The Eastman organisation has its tentacles spread throughout
the world. It has thousands of agencies in immediate touch with the
different national companies. The result is that this film can be
purchased without difficulty in nearly all parts of the globe. If a
local dealer does not stock it, he can procure it to order within a
day or two. Moreover the film will be new and in perfect condition.

There are many other reasons why it is advisable to select and to
adhere to this stock, which, although of a technical character, are of
much importance to the user. It must be borne in mind that the technics
and chemistry of cinematography are still in their infancy, and the
technical staff retained for the preparation of the various ingredients
employed in the sensitizing of the film are striving constantly to
improve and to increase the speed or sensitiveness of the emulsion.
The result is that the worker who uses Eastman film keeps pace with
developments. The makers of this ribbon were the first to discover a
base and emulsion suited to moving-picture work. This was achieved
only after the expenditure of enormous sums of money, after hundreds
of fruitless experiments, and with the co-operation of the highest
technical and chemical skill. Under these circumstances the limitations
of the base and of the emulsion become thoroughly understood, so that
the film is certain to maintain the highest quality. On the other hand,
those firms who have embarked upon the manufacture of the commodity
only within recent years, have still to face and to overcome many
pitfalls which the older concern discovered and surmounted years ago.
So the film marketed by younger organisations is apt to vary in its
quality.

[Illustration: A WELL-EQUIPPED DARK ROOM SHOWING ARRANGEMENT OF THE
TRAYS.]

[Illustration:

 _By permission of Jury's Kine. Supplies, Ltd._

WINDING THE DEVELOPING FRAME.

The film is transferred from the exposed film-box to a revolving frame,
emulsion side outermost.]

Before the beginner attempts development he must make sure that his
dark room and accessories are adequate. To seek success with makeshifts
in the first instance is to court heart-rending failure. Many of the
utensils employed in the dark room can be fashioned by any handy man.
They may lack finish, but so long as they perform their work properly
nothing more is necessary.

The dark room must be spacious, for cramped conditions are fatal to
satisfactory work. An expert will perform his task successfully, if
the exigencies arise, in a small cupboard, but the beginner will find
that the more space he has at his command the easier he will be able to
complete his task. The room should measure 10 feet in length by 6 feet
wide at least. In a corner, or at some other convenient point along the
wall, there should be an ordinary sink provided with free waste and
with ample supplies of water laid on to a tap above. On one or other
side of this sink, there should be a bench, 3 feet in width, for the
purpose of the developing, fixing, rinsing, and other baths.

At least four trays will be required, three being for solutions and one
for rinsing. Each tray should be at least 33 inches square inside, by
about 6 inches in depth. These trays may be made of wood throughout,
with dove-tailed sides, and tongued and grooved bottom, or the bottom
may be made of glass. If the work of dove-tailing seems too difficult,
the sides and bottom need only be nailed or screwed together, but in
this case a lining of waterproof fabric should be fixed to the wood.
Trays of this type are inexpensive, and are quite as good as those of
a more elaborate character. In some developing works lead-lined trays
are used, but they are weighty and cumbersome to handle. In order to
draw off the solution when necessary it is well to fit a drain and plug
in the bottom of the tray by which the contents can escape into the
storage vessel placed beneath the bench.

Sometimes a vertical tank is used. This system is maintained to be the
most satisfactory as it enables the solution to be kept more easily in
movement. The tank, in this case, should be 33 inches high by 33 inches
wide, and 6 inches from front to back. These are inside measurements.
It must be lined with waterproof material or with thin sheet lead in
the same manner as the tray. For the purposes of the small worker,
the tank process is more expensive, owing to the greater quantity of
solution that it requires; so, for ordinary and limited working, the
tray is recommended. It should be fitted with a rocker so as to enable
the solution to be kept flowing evenly over the surface of the film.

[Illustration: Fig. 2.--The "Pin" Frame.]

The film is mounted upon a special frame. A frame made of wood is most
generally used. This likewise a handy man can make at home, although it
is not expensive to buy. The middle of each side of the frame is fitted
with a short pin to serve as a spindle and to facilitate spinning
round when the frame is mounted upon its stand. Each transverse end is
provided with guide pins for winding the film.

The other type is known as the pin frame. Its design may be gathered
from Fig. 2. It is a light skeleton frame with vertical pins projecting
from the four diagonal members. The spool is slipped on the central
spindle and the film is unwound and passed round the pin on one
diagonal, then to the relative pins on the three other members. It is
then taken round the second pin on the first diagonal, followed round
the relative pins on the other three members, and so on until the whole
film has been uncoiled, the pins on the other four cross members being
called into requisition as additional supports when the frame is about
half covered. When the film is mounted upon this frame it is in the
form of an endless square spiral. When the frame is laid in the bath of
solution the film stands edgewise. The wooden frame, however, is now
almost exclusively used, as it is easier and simpler to work. The film
can be transferred to it in a shorter space of time, and the frame with
the film upon it can be handled more safely.

The ruby light may be either electricity, gas, or oil, but extreme care
must be taken to make absolutely certain that the light is non-actinic,
and is not too powerful, otherwise the film, which is extremely
sensitive, will be fogged during development. The safety of the light
may be tested in a very simple and easy manner. Cut off about 6 inches
of film from the unexposed reel, lay it flat upon the developing bench,
emulsion side uppermost, in full view of the ruby light. Place two or
three coins upon the emulsion and leave them there for a few minutes.
Then develop the strip in a covered dish. If the space surrounding the
places where the coins were laid comes up grey, then it shows that the
light is unsafe, because the exposed emulsion surrounding the coins has
become fogged. On the other hand, if no signs of the position of the
coins are revealed upon the developed strip, the light is perfectly
safe.

The trays should be placed side by side along the bench. The one which
is used for developing should stand furthest from the ruby light.
If space will allow, the rinsing bath should be placed next to it,
but if this is impossible the fixing bath may be placed there. A
division board should be set up between the two trays, rising some 10
or 12 inches above their upper edges. This will prevent the fixing
solution splashing into the developing bath and spoiling it. Various
formulae have been prepared for development, each of which has certain
advantages. As may be supposed, each firm has evolved a formula which
it has found from experience to give the best results. Obviously
these formulae are secret. But the most satisfactory for the beginner
is that advocated by the Eastman Company. It possesses the advantage
of having been prepared by the chemists who are responsible for the
emulsion, who understand its particular characteristics and also its
limitations. The majority of other formulae are based more or less upon
this one, which is applicable and adaptable to all kinds of work. It
has the quality of bringing the picture out to the utmost degree, and
by its means many of the errors in exposure may be corrected during
development.

The developing solution is made up as follows:--

  ------------------------------------------------------------------
                               |      Avoirdupois.  |   Metric.
                               |------------------------------------
  Sodium sulphite (des.)       |         53 oz.     | 1,575 grammes
  Sodium carbonate (")         |         25  "      |   750    "
  Metol                        |        180 grains  |    12    "
  Hydrochinon (hydroquinone)   |          8 oz.     |   237    "
  Potassium bromide            |   1 oz. 63 grains  |    34    "
  Citric acid                  |        400 grains  |  27.5    "
  Potassium metabisulphite     |          2 oz.     |    60    "
  Water  (Imperial measure) }  |    8-1/3 gallons   |
    "    (United States " ) }  |           10  "    |    40 litres
  -------------------------------------------------------------------

The ingredients must be mixed in the order indicated. All the chemicals
are readily and cheaply obtainable at any photographic chemists and
drug stores. After preparation the developer will keep for a long
period so long as the bottle is well stoppered and kept in a cool
place. Only the highest grade chemicals of a reputable brand should
be used. A slight saving in the purchase of these essentials is false
economy, because a film costing one hundred or more times the money
saved in the outlay upon chemicals may thus be ruined.

In cases of over-exposure, perhaps the most common fault of the
beginner who does not understand the stopping down of the lens, a
restrainer is necessary. This is composed of the following:--

  --------------------------------------------------------------
                       |   Avoirdupois. |       Metric.
                       |----------------------------------------
  Potassium bromide    |      1 oz.     |      30 grammes
  Water                |     10 oz.     | 300 cubic centimetres
  --------------------------------------------------------------

The process of development is as follows. First, the film is
transferred from the dark film-box of the camera to the frame. The
latter, if it is of the wooden type, can be spun round freely when
mounted on its stand. It is not advisable for the beginner to withdraw
the coil of film bodily from the box until he is expert in winding the
frame, otherwise, to his surprise and disgust, the spool may fall out
and the film be precipitated to the floor in an inextricable tangle.
He should let it remain in the dark box until it is removed by being
drawn slowly through the velvet-lined slot. The free end of the film
should be fixed with a drawing pin to one end-bar of the frame, and
contained between two guide pins, with the emulsion side outermost. The
emulsion side can be recognized even in the subdued light of the dark
room because it has a matt surface, while the other side is glossy. The
difference between the two sides can also be detected by the touch.
When the end of the film has been attached to one end-bar the frame is
turned, the film meanwhile being permitted to slide out of the dark
box, until the opposite end of the frame comes up. The film is passed
over this bar, also between the first pair of guide pins, and once
more, with a half-turn to the frame, the film passes along the second
side of the frame back to the first bar, between the succeeding pair
of guide pins, over the top and back again to the opposite bar, this
process being continued until the coil of film is unrolled, when the
second extremity is likewise fixed to the bar by means of a drawing
pin. The film while being wound must not be drawn too tightly; at the
same time it must not be too slack. When winding has been completed,
the frame and film will have the appearance shown in the illustration
facing p. 65. The guide pins in the end-bars prevent the edges from
overlapping or touching. The result is the presentation of two
emulsion faces on either side of the frame and each face resembles the
sensitized side of a dry plate.

[Illustration: THE FILM TRANSFERRED FROM THE DEVELOPING FRAME TO
THE DRYING DRUM.

For amateur use a small drum can be used.]

[Illustration:

 _By permission of Williamson Kine. Co., Ltd._

THE FILM WOUND ON FRAME AND PLACED IN THE DEVELOPING TRAY.]

[Illustration:

 _By permission of Jury's Kine. Supplies, Ltd._

THE JURY COMBINED CAMERA AND PRINTER.]

In winding the film upon the frame, and indeed during all the
operations, the operator should be careful not to touch the gelatine
coating of the ribbon with his fingers. The finger nails should be
kept well trimmed so that scratching may be avoided. A touched film
is usually marked, for the touch leaves a deposit of grease, which
interferes with the action of the developer.

The frame, with the film wound upon it, is lifted off the stand and
carefully placed in the developing bath, into which the developing
solution has already been poured. If it is inserted gently no air
bubbles or bells will form on the emulsion, but if there should be any
such they can be removed at once by means of a large, flat, soft, camel
hair brush. In order to secure first-class results, the developing
solution should be kept at a temperature of 65 deg. Fahr.

The developing solution is rapid in its action and the film must be
watched closely. The frame must be kept rocking so that the solution
may remain in movement. This enables it to act upon the whole surface
of the film equally. Should development take place too quickly--(_i.e._
the images flash up almost instantly)--the frame should be removed at
once from the developer and immersed in the rinsing tray to allow a few
drams of the restrainer solution to be poured into, and mixed with, the
developer. On the other hand the film may be under-exposed, and then
the images will appear very slowly.

Development proceeds exactly as in the case of a glass plate, and
the same judgment is required to determine when the process has been
carried far enough. When this point has been reached the frame is
lifted out of the developer and placed in the rinsing tray to receive a
thorough washing. Water is a kind friend in cinematography and should
be used ungrudgingly. Three or four thorough flushes will suffice to
rinse the film satisfactorily, and then the frame is placed in the
fixing bath. This is made up as follows:--

  ----------------------------------------------------
                        |  Avoirdupois.  |  Metric.
                        |-----------------------------
  Water                 |  64 oz. (fluid)| 2,000 c.c.
                        |                |
  Hyposulphite of soda  |  16 "          | 480 grammes
                        |                |
  Sulphite              | 3/4 "          |  22   "

  When fully dissolved add the following hardener.

  Powdered alum         |    1/2 oz.     |  15 grammes
                        |                |
  Citric acid           |    1/2 "       |  15   "
  ----------------------------------------------------

During fixing the frame should be kept rocked so that every trace of
undeveloped silver salts may be removed from the film. Then it is
transferred to the washing tray and submitted to a thorough washing
in frequent changes of water for some twenty minutes. The film is
now ready for its final treatment. This is immersion in the soaking
solution:--

  ----------------------------------------------
                 | Avoirdupois. |    Metric.
                 |------------------------------
  Water          |      32 oz.  |  1,000 c.c.
  Glycerine      |       1 "    |     30  "
  ----------------------------------------------

This final bath is not always used, but it is desirable if the negative
film is to be kept for any length of time. Immersion in this soaking
solution prevents the gelatine coating of the film from becoming hard
and horny. After remaining in this bath for five minutes the frame is
lifted out, and returned to its stand, where the excess of glycerine
and water is removed by wiping with a soft cloth.

It will be seen that once the film is wound upon the frame it is not
removed during the whole process of development, and may be left in
the same position during the drying period. But if the drying is to
be quickly performed the frame must be of what is known as the spring
type, so that it does not keep the same area of film constantly
pressing upon the curved end-bars. Otherwise the film would retain
this shape when it has been dried and the kink would be irremovable.
To avoid this defect it is just as well to transfer the film from
the frame to a drum (see illustration facing p. 72). This is an easy
matter. The drum is mounted upon a stand so as to be free to revolve
easily. Detach one end of the film from the developing frame, and
attach it to the drum by means of a drawing pin. The emulsion side, of
course, must face outwards. Then by unwinding the frame and rotating
the drum simultaneously the film becomes wound spirally upon the
drum. Another pin will secure the second end of the film. The drum
is an inexpensive and very handy accessory to the moving-picture
photographer, especially in the drying operation, when forceful methods
have to be adopted.

Unfortunately the drying of the film cannot be accelerated to any great
extent. The hardening of the gelatine emulsion cannot be hastened, as
in glass plate work, by immersion in a bath of methylated spirits or
some other evaporative agent, since the alcohol contained therein would
dissolve the celluloid base. The only available means is a current of
warm, dry, clean air. While the well-equipped factory is fitted with
a special drying room, such a facility is beyond the resources of the
average independent worker, who must therefore be content to revolve
his frame or drum continuously, until the gelatine has hardened
sufficiently. The process can be accelerated to a certain extent by
revolving the drum or frame over a steam radiator, or some other form
of heating which emits no smoke or flame, but the temperature of
the air must not be raised too high or the gelatine coating will be
injured. If the weather is fine and calm, the drying may be done upon
a lawn in the open air, but in any event extreme care must be observed
to prevent dust settling upon the gelatine while it is wet and soft, or
irreparable injury will be inflicted. So it behoves the worker to keep
his dark room and drying room free from dust. Drying should not be done
in the dark room because there are small particles of chemical dust
always floating about in such surroundings. If these should settle upon
the emulsion they would play sad havoc with it.

When the gelatine has hardened the film may be transferred direct
from the drum to a spool by means of a winder. When the beginner has
become expert he will be able to do this by hand, but it is never a
wise practice since the coating is liable to become scratched. The
spool-winder is inexpensive and does the work much more quickly, while
the risk of damaging the film is eliminated.

As has been mentioned, it is well to develop the film as soon as
possible after exposure. Although the exposed film is kept in a dark
box, the chemical action set up by exposure before the lens, continues,
as in dry-plate and snap-shot photography, and in a more rapid manner.
Consequently the film should not be left undeveloped for more than a
few days at the utmost. While prompt development is usual in topical
work, there are other sorts of work in which the operator may feel
tempted to put the film on one side for development at a later and more
convenient time. Perhaps several weeks may elapse, and then complete
amazement is expressed at the result. In the unexposed condition,
however, Eastman stock will last many months so long as it is not
removed from the case in which it is packed at the works. Equal care
must be used in storing the developed negative films. They must be kept
in a cool dry place, protected from severe fluctuations in temperature
and climatic effects.




CHAPTER VII

PRINTING THE POSITIVE


Theoretically there is no operation in the whole art of cinematography
which is more complex than the preparation of the positive. This is
used for projecting the image on the screen, and is the result upon
which popular criticism is passed. Also, in the process of printing the
positive, several short-comings in the negative can be corrected.

At the same time, from the practical point of view, the preparation
of the positive is simple. The beginner who has mastered the somewhat
intricate process of development, need not apprehend any greater
difficulties than those he has already overcome before he essays to
print his positive. In practice he will soon become proficient, though
he may retain rather hazy ideas of the theory of the matter.

The essentials for the preparation of the positive are a printing
machine and an illuminant. The appliances and methods of operation
differ completely from those used in any other branch of photography,
so that a new art virtually has to be mastered. Fortunately, the
beginner gets assistance from those masters of the craft, who, having
left the producing for the manufacturing side of the industry,
willingly give advice to the tyro. By following the few rules which
these early workers lay down, the beginner will not go far wrong, and
will not run the risk of incurring many dispiriting failures. While the
large professional firms use elaborate and costly printing machines,
the amateur is able to get just as good results with simpler and
cheaper apparatus. He could not wish for a better equipment than the
Williamson printer, which costs only L4 10_s._ ($22.50), or the Jury
Duplex, which is a combined camera and printer.

So far as the illuminant is concerned this depends upon circumstances.
In most towns it is possible to obtain electric light, which is the
simplest, and taken all round, the most reliable and satisfactory
illuminant. If this is not available, gas and an incandescent mantle
may be used. Failing either of these conveniences, acetylene or petrol
gas, the latter with the incandescent gas mantle, can take their place.
Even daylight may be used.

Success in printing depends upon a correct judgment of the intensity of
the light, and of the density of the film. This enables one to estimate
the exposure required. Obviously this knowledge can only be acquired
in the school of practice. The same experience is needed to estimate
the length of the exposure in making lantern slides, or in bromide
printing. But it must be borne in mind that in the cinematograph film
one is working with a much more sensitive emulsion.

A very good practice for the beginner is to make experimental exposures
with short lengths of film--say 12 inches--making the tests with
sections of the negative which vary in density, at various distances
from the light, and at different speeds. A careful note should be
made of each trial. In this way one can estimate the exposure and
learn how it should be varied at different points of the negative
where the density varies. Moreover, the knowledge will be acquired at
comparatively little expense.

If the negative has been over-exposed or over-developed, or both, a
common error in the first attempts, it will naturally be very dense,
and will demand a longer exposure, or a more powerful light, than a
negative which is exposed correctly. This situation may be met either
by slowing down the process of printing, or by bringing the light
nearer to the film. On the other hand, if a negative is under-exposed
it had better be destroyed at once, as it is worse than useless. An
over-exposed negative will yield a passable print, possibly somewhat
harsh, but nothing can be done with a negative which is deficient in
detail. The only exception that may be made to this drastic policy is
the topical film, which may have been taken under adverse conditions,
during a fog, or in heavy rain, or on a dull day, or at a late hour
when the light was bad. In the topical film it is more the interest of
the event than the quality of the film that is important.

For absolute simplicity it would be difficult to excel the system
adopted in the Jury Duplex camera. In this case one obtains both camera
and printing apparatus--without the lens--for the modest outlay of L8
($40). There is a small bracket mounted upon the outer top face, and
near the front edge, of the case. This bracket carries the spool on
which the negative film is coiled. This is slipped on the bobbin and
locked in position by means of a small lever. The film is carried from
this spool between two small guide pressure rollers and fed into the
camera through a slot faced with velvet, like that provided in the dark
boxes. The film is pulled down a sufficient distance to enter the gate
so as to secure engagement by the claws of the camera mechanism. In
threading the film care must be used to bring the emulsion side facing
the dark boxes and the glossy side facing the lens.

The positive film is inserted in the unexposed film-box of the camera
and is threaded up as if for taking photographs. As the emulsion
side is uppermost, when the unexposed film meets the negative in the
gate, the two films are brought together with their emulsion sides in
contact. As one film is laid squarely over the other, and with the
perforations in line, it will be seen that the claws engage with both,
so that the two films are jerked together intermittently through the
gate.

Emerging from the gate the two films part company. The exposed positive
ribbon passes into the exposed dark box, while the negative film passes
through another velvet-lined slot in the bottom of the camera, and then
is wound up on another spool.

It will be seen that in this case printing is carried out in a manner
similar to photographing. The film is run through the camera in the
ordinary way by turning the handle, and the number of exposures per
second can be varied within wide limits to suit the density of the
film. The camera is supplied with a second spindle and gearing upon
which the handle may be slipped. The ratio of this gearing is one
exposure per revolution, or as it is termed "one turn per picture."

Owing to the positive film being contained within the camera, and
therefore in a light-tight space, the electric light or other
illuminant may be mounted upon the bench within the dark room, so that
the operator can work in a lighted apartment. In this arrangement,
however, the camera should be clamped firmly to a rigid foundation, so
that it may not move during exposure. This also ensures that the light
should remain at a constant distance from the machine.

This camera can be adjusted easily and cheaply for the purpose of
daylight printing. All that is required is a square funnel, about two
feet in length, made of wood and so designed that the smaller open
end fits into the front recess of the camera after the shutter panel
is removed or opened. This funnel should be made after the manner of
a Kodak enlarger, and blackened on the inside, with a dull medium, so
that no reflections of light are set up. When this funnel is attached
it is only necessary to stand the camera on its rear face so that the
opening of the funnel points directly to the clear sky overhead, not
towards the sun, and to turn the handle upon the one turn one picture
gear. The printing speed will vary with the intensity of the light and
the density of the film. Obviously the camera can be run more rapidly
on a bright summer than on a dull winter day. In the first case it is
safe to turn the handle as fast as possible, but in the second the
speed would need to be about one picture, or handle turn, per second.

[Illustration: THE WILLIAMSON PRINTER.

(For explanation see p. 85.)]

[Illustration:

 _From the "Cinema College," by permission of the Motograph Co._

WATER BEETLE ATTACKING A WORM.]

One advantage of this system of printing is that the picture is
printed with the camera with which the negative was obtained, and so
first-class results are inevitable. The registration is assured as
well as the alignment. In threading up the camera it is only necessary
to make sure that the image on the negative comes squarely and truly
before the window in the gate. Once this is so, every successive
picture must be in perfect registration and alignment. There could
be no method of printing more suitable for those who are travelling,
or engaged on topical work, often under trying conditions, for the
conversion from photographing to printing, and _vice versa_, may be
accomplished in an instant. Some of the more expensive cameras costing
from L20 ($100) upwards are now fitted with a printing attachment, the
printing accessory being detached when the instrument is being used for
photographing purposes. These cameras follow where the Jury Duplex led
the way.

The Williamson printer works upon a different principle, being a
distinct and separate machine. Nevertheless it is an eminently
practical appliance, and is as well adapted to the factory as to the
amateur's dark room. It comprises a base board on which the whole of
the mechanism is mounted, together with the stand for the light. (See
illustration facing page 84.)

In this installation there must either be a dark box to contain the
light, against the face of which the base board of the printing
mechanism is screwed, or else an aperture must be provided in the wall
of the dark room and the light be placed on a shelf outside. The handy
man, however, will be able to devise a light-tight box, either for
the electric light or gas. In the latter case it must be fitted with
a chimney with baffle plates absolutely light-tight, to carry off the
products of combustion. The light-tight box should be lined either
with absolutely safe ruby fabric, or with orange and ruby fabrics
superimposed. If wood is used, the light-box is apt to split under the
influence of the heat within.

The Williamson printer is of the simplest design conceivable. There
is an upper spindle A (see illustration facing p. 84) on which the
spool containing the negative is carried. Immediately below is another
spindle carrying the spool B on which is slipped the coil of unexposed
film. The negative film, emulsion side outermost, as it winds off
the spool A is passed behind the guide roller C and then picks up
the unexposed film of spool B. The emulsion side of the unexposed
film comes into contact with the emulsion side of the negative film.
Passing over another guide roller D the films pass together between
the two rollers E to enter the gate F. The latter is mounted upon
the rear face of a small chamber, the aperture of which is of the
size of the cinematograph film image. This aperture is provided on
the inside with a small hinged shutter. By opening this one can see
that the negative image occupies the full space of the window, or make
any other observations. The film is moved intermittently through the
printing gate F by the sprocket wheel G, the teeth of which engage
with the perforations in the films. The engagement of the films with
this sprocket is ensured by the two pressure rollers H. The sprocket
G is mounted upon and revolved by the handwheel I--a motor drive can
be incorporated if desired--and after being moved beyond this sprocket
wheel, the two films divide, the positive film being wound upon a
spool or into its dark box, while the negative is wound upon another
spool. The movement of the light K, either towards or from the exposure
window F, is effected by means of the handle J, which has ten stops
corresponding to as many different distances. The lamp moves to and fro
along the support L.

It will be seen that the Williamson is a simple, straightforward
machine. It is soundly constructed and works admirably. Its
achievements are in every way equal to those of the complicated
and more expensive model manufactured by the same firm for
professional use.[2] So long as the machine works reliably, and has
perfect registration and alignment, nothing more is required. Extra
refinements, and little details, while of service to the expert, only
serve to harass the amateur.

[2] "Moving Pictures: How they are Made and Worked," Chapter
VIII., page 82.

As a matter of fact the most important duties of a printing machine are
to feed the two films evenly and easily through the gate, and to hold
them flatly and tightly together, so as to secure perfect contact while
they are before the exposure window. By this instrument both these
duties are perfectly performed. The sprocket G continuously revolves
under the steady turning movement of the handle, and the two films are
held rigidly, tightly and steadily together by the pressure gate F.

Of course, in printing with this machine, the operator works in total
darkness, owing to the coil of positive film being fully exposed.
This is no handicap however, because the dark-room ruby lamp supplies
sufficient light to enable the necessary operations to be performed.
But it is not wise to use too powerful a ruby light, or the unexposed
positive film will be fogged.

Turning the driving handle is no more difficult than turning that of
the camera mechanism. The gearing is so designed that six exposures
are made per revolution, representing twelve pictures per second, when
revolved at the normal speed. With a negative of average density this
speed is sufficient. But the period of exposure can be varied according
to the speed at which the handle is turned. The turns of the handle
should be steady and regular, or the pictures will be of uneven density
owing to the variations in exposure.

The electric light is easily moved by means of the handle while the
ten stops give it great flexibility. In order to maintain an exposure
of twelve pictures per second with an average negative, a lamp of 50
candle power should be used. To ensure the best results it should
be of the class known as "focus lamp." This type of lamp has a
special filament, with a smaller coil than is found in the ordinary
incandescent electric lamp. A gas burner with incandescent mantle may
be used if electricity is not available, though the operator will have
to ascertain the relative value of the luminous intensity of the light
as compared with the 50 candle power electric light, and will be wise
if he makes one or two trial exposures with short lengths of film
before essaying the printing of a complete film.

While it is possible during printing to vary the distance of the
light from the exposure window, the light being manipulated with the
left hand, while the handle is turned with the right, there is slight
necessity for such a procedure. The negative film should be examined
to ascertain how the density varies along its length, and then each
portion of film that shows tolerable regularity of density should be
printed off at the same speed. In this way variations of distance need
occur only with distinct lengths of film. This is a far safer method,
especially for the beginner, than the movement of the light to and fro
while the films are running through the gate, though of course with
practice it becomes possible to do the two things satisfactorily at
once. Many amateur cinematographers make the mistake of attempting
artifices which they have seen practised by some experienced
professional worker, and the result is failure. What is easy and simple
to the expert is often beyond the powers of the beginner. Success in
printing can only be achieved by honest and diligent work, but patience
is sure of its reward. At first there may be a tendency to make the
positives somewhat too dense, and then, when the evils of this defect
are appreciated, to fly to the opposite extreme. Of the two blemishes
probably the latter is the worse, as it produces a washed-out effect
upon the screen.

The positive is developed in exactly the same way as the negative,
and with the same solutions. When dry the positive, which may have
been printed in short distinct lengths, should be connected up with
the aid of cement as described in a previous chapter. If titles have
to be introduced they may be inserted wherever required, merely by
severing the film at that point, and introducing the length carrying
the explanation.

The preparation of the titles is a simple matter. If printed type is
used, the letters cut out of white paper or cardboard are laid flat
upon a level surface with a black background. The camera is then placed
overhead with the lens pointing downwards upon the centre of the title
space. The latter, brilliantly illuminated, is then photographed at the
rate of sixteen pictures per second for a period of ten seconds or more
according to requirements.

In many instances, especially in non-topical work, the operator need
not necessarily incur the expense and trouble of printing a positive
film. Many of the purchasers of educational and popularly scientific
films will give their decision after having seen the negative passed
through the projector in the manner of a positive film. So long
as great care is used, this can be done without ill effects, but
of course the slightest scratch or abrasion that the negative may
receive in the process will be reproduced with accentuated effect
upon the positive film. Even with some of the topical films a positive
is not necessary. To submit the negative to the local theatre or
prospective purchaser is often a good way of saving time and being
first in the field. Many theatres now are being equipped with dark
rooms and printing machines. A glance at the negative will enable
the manager to decide whether the film is serviceable or otherwise,
and if a purchase is made, the deletion of the uninteresting parts
can be made before printing. Incidentally, one great advantage of
this is that the film is submitted for consideration about three or
four hours earlier than would be the case if the independent worker
struck off his own positive, and in these days of high pressure such
a saving is important. It may often be the means of forestalling a
competitor. Even if it is intended to supply prints to two or three
different picture palaces the negative offers a means of transacting
business, because the respective establishments can give their orders,
make their arrangements concerning announcements, and be able to judge
fairly accurately the hour at which the film will be available for
projection. In one instance an independent topical worker who had a
first-class negative of a popular subject drove round from theatre to
theatre with his negative and secured an order for about half-a-dozen
copies. He then handed over the work of printing to a professional
firm. Four hours later he delivered the positives to the respective
theatres, and ultimately he sold the negative outright to the firm who
completed his printing contracts for the supply of other markets at
their disposal. In another instance an enterprising amateur who had an
excellent negative handed it over to a topical-film firm to print and
circulate, the firm to take fifty per cent. of the receipts and to bear
the expense of printing and other details.




CHAPTER VIII

ABERRATIONS OF ANIMATED PHOTOGRAPHY


It has been pointed out in a previous chapter that cinematography
is nothing more or less than an optical illusion. Further proof of
this assertion exists in plenty. When following the projection of a
picture upon the screen, one is often perplexed by a curious effect,
or a movement which appears to be in opposition to all the known laws
of motion. This happens not only in trick work where such odd and
startling effects are introduced purposely, but in straightforward
every-day topical subjects.

For instance, it must have been noticed that when a ship or railway
train is in rapid movement, and is photographed from a fixed stationary
point, such as the quay or platform, the moving object appears to
stand out in bold relief against the background. One gathers a very
comprehensive idea of its length, width, height, and the comparative
size of all its integral parts, such as the guns on the ship's deck or
the locomotive's cylinders. It is a curious stereoscopic effect, but
at the same time is not truly so, because it is only the moving object
which appears to possess solidity. The foreground and background
remain as plane surfaces so that it is impossible to obtain an idea of
distance. This effect arises from the fact that what might be described
as the central part of the picture is moving or continually changing,
thereby compelling all the objects attached to its length and breadth
to assume relief in regard to the other parts of the picture.

But if the camera with which the pictures are taken is placed upon the
moving object itself, then the whole of the resulting picture stands
out in a truly stereoscopic manner. One gathers an impression of
distance between the various objects on the screen. Everything is shown
with form and solidity in precisely the same way as if one were looking
through a hand stereoscope upon a photograph taken stereoscopically.
This effect is due to the fact that all the planes are moving
continually.

But probably the most bewildering puzzle is the moving wheel. A
carriage or waggon is seen advancing across the screen from left to
right, but the spokes of the wheels, on the other hand, seem to be
moving in the opposite direction. At other times the spokes move in
successive spasmodic jumps, or appear to be stationary, so that a
curious skidding effect is produced, notwithstanding that the rim
itself is seen to be revolving normally.

There have been many explanations of this extraordinary effect, and in
one instance the higher mathematics were pressed into service without
any great success. The most convincing explanation known to the writer
is that given him by Monsieur Lucien Bull, the assistant-director
of the Marey Institute, where phenomena of this class are minutely
investigated, because they accord with the work of that unique and
admirable institution. By Monsieur Bull the illusion was explained very
easily, but, curiously enough, in carrying out the experiments to this
end, he encountered another illusion equally strange.

[Illustration: Fig. 3.--The first picture of the four-spoke
wheel.]

[Illustration: Fig. 4.--During the eclipse of the lens the
spokes have moved a distance equal to the angle between them, causing
the spokes apparently to stand still while the wheel is moving.]

To reduce the explanation to its simplest form we will suppose that a
wheel has four spokes spaced equidistantly, that is, 90 degrees apart,
and that the wheel is moving from right to left. As a matter of fact
such an example is not the best for the purpose, but it shall be taken
merely because it is the simplest to understand. An exposure is made,
the wheel being photographed in the position shown in Fig. 3. The lens
is eclipsed by the shutter, and the film is jerked downwards into
position in the gate so as to bring a fresh unexposed surface before
the lens. While this operation is taking place, we will suppose that
the wheel, continuing its forward movement, completes one quarter of a
revolution. Consequently when the second exposure is made spoke 1 has
moved 90 degrees, which is the angle between each spoke. Accordingly
it now occupies exactly the same position as that of spoke 2 at the
time of the first exposure. Spoke 2 has moved to the position formerly
occupied by spoke 3. Spoke 3 has travelled sufficiently to take the
place of spoke 4, while 4 has gone to that of 1 (Fig. 4). If four
exposures are made, and the spokes move 90 degrees each time the lens
is closed, when the four pictures are thrown successively upon the
screen they will look exactly alike. The spokes will appear to be
quite stationary, although the rim of the wheel will have moved a
distance equal to its circumference across the screen. Consequently,
if a dozen, a hundred, or a thousand exposures are made under these
conditions, the spokes moving 90 degrees between each exposure, a
quaint skidding effect will be produced. All the spokes being alike the
eye is unable to detect that any displacement has taken place between
one exposure and another. This impression of the spokes standing still
while the wheel is moving, must arise in every case in which the wheel
moves sufficiently to cause the spokes to cover a distance equal to
the angle between them during the interval while the lens is eclipsed
by the shutter. It will happen equally whether the wheel has four,
sixteen, or more spokes.

[Illustration: Fig. 5.--During the eclipse of the lens the spokes move
less than the angle (AB) between them, producing apparent backward
motion of the spokes while the wheel is running forwards.]

[Illustration: Fig. 6.--During the eclipse of the lens the spokes move
more than the angle (AB) between them, and accordingly the wheel is
seen to be moving naturally.]

Now we will suppose that the revolving speed of the wheel is retarded,
causing less than a quarter of a revolution to be completed between
each exposure. The spokes, let us say, move through an angle of 85
degrees instead of 90 degrees while the lens is eclipsed. The eye
at first receives the impression shown in Fig. 3. As the wheel only
covers 85 degrees during the eclipse, in the second picture the eye
observes that movement has occurred. Spoke 1 is now behind the point
formerly occupied by spoke 2 (shown by the dotted line in Fig. 5) in
the first exposure. The lens is eclipsed once more, and the spoke moves
another 85 degrees. When the next picture is seen spoke 1 has fallen
still farther behind the 90 degrees mark, and this indication of less
movement than the right angle becomes accentuated with each succeeding
exposure. Accordingly, the spokes in the successive pictures appear
to be moving at a less speed than the rim of the wheel, and forthwith
the eye imagines that the spokes are travelling backwards, although
meantime the wheel rim is seen to be advancing across the screen. This
remarkable effect is produced whenever the advance of the wheel is such
as to cause the spokes to move less than the angle between them, no
matter what the size of the angle may be.

We will now suppose that the revolving speed of the wheel is
accelerated so as to cause more than a quarter of a revolution to
be made while the lens is eclipsed--that the spokes move forward 95
degrees between each exposure. In this case, while the first picture
will show the position indicated in Fig. 3, the next exposure will show
spoke 1 in the position shown in Fig. 6, that is, in advance of the
angle of 90 degrees and in advance of the position occupied by spoke
2--(see the dotted line)--in the first exposure. In the third picture
the spoke will be shown still farther in advance of the right angle
mark, and the effect will be produced of the spokes apparently gaining
upon one another. When a series of pictures taken under such conditions
is thrown upon the screen in rapid succession, the spokes and rim will
be seen to be moving harmoniously in the forward and correct direction.
Accordingly natural movement of the wheel only can be shown when the
spokes of the wheel, irrespective of their number, move a distance
equal to more than the angle between them.

[Illustration: Fig. 7.--When the spokes move slightly more (AC) or
slightly less (AD) than half the angle (AB) between them, during the
eclipse of the lens, the curious illusion of seeing twice the number of
spokes in the wheel is produced.]

In the course of elucidating this problem Monsieur Bull discovered
another curious optical illusion produced by the moving wheel. Still
taking the four-spoke wheel as an illustration, we will suppose that
between each exposure the spokes are displaced a little more or a
little less than half the angle between them. As the spokes are set 90
degrees apart, the half-way point will be 45 degrees. When a succession
of such pictures is thrown upon the screen, it is not four spokes which
are seen, but eight (Fig. 7). Monsieur Bull is engaged upon a series
of experiments to ascertain why this peculiar optical illusion should
prevail, and the explanation will prove interesting.

Another interesting and more conclusive illustration of the optically
illusory properties of the cinematograph was demonstrated to me by
Monsieur Bull. In order to be absolutely positive that an apparatus
which he uses in certain cinematographic investigations should maintain
the speed he desires, he has contrived a tuning-fork control for his
electric motor. This tuning-fork resembles a large trembler blade, such
as is used in the high-tension accumulator and coil ignition system
upon motor cars. This particular instrument is timed to make, say,
40 vibrations per second, and at this speed, of course, it emits a
distinctive musical note. This tuning-fork controls the electric motor
driving the apparatus. For the purpose of illustration we will suppose
it to be necessary that the speed of the motor shall not exceed 40
revolutions per second. In the earliest experiments he depended upon
his ear to detect whether the motor and tuning-fork were in synchrony.
He varied the speed of the motor until its hum was dead in tune with
that of the tuning-fork.

But, as he thought that his ear might not be infallible, he devised
an ingenious synchronising apparatus based upon the cinematographic
principle. A small disk of cardboard provided with two holes near
its edge, at opposite points of the circumference, is mounted upon
the spindle of the tiny motor. Behind this disk is placed a small
adjustable mirror. A pencil of electric light is projected horizontally
in such a manner that it strikes the cardboard disk at right angles,
and, when a hole on the disk is brought into line with it, it passes
through and falls upon the mirror. The mirror is then set so as to
reflect and focus the pencil of light in a small circle upon the free
vibrating extremity of the tuning-fork. Naturally a strong shadow is
thrown by the latter upon the white wall behind.

In the daylight the vibration of this fork is distinctly visible, and
although it is slight and rapid it can be followed without any effort.
But when the room is darkened, the ray of light is thrown upon the
tuning-fork from the mirror. When the motor bearing the cardboard disk
is set in motion a very curious effect is produced. The pencil of light
reflected against the tuning-fork becomes interrupted twice in every
revolution of the disk, that is 80 times per second, so that, looking
at the background upon which the tuning-fork is silhouetted, the effect
produced is precisely similar to that observable upon the cinematograph
screen, where the passage of the light from the lantern is interrupted
by the rotary action of the shutter. If the revolving speed of the
motor, that is the number of revolutions per second, is the same as the
number of vibrations per second of the tuning-fork, viz. 40, the end of
the fork, as one looks at the illuminated circle on the wall against
which the shadow is thrown, appears to be at rest. One only needs to
touch the end of the fork, however, to be certain that it is vibrating.

Now if the motor be thrown out of synchrony with the tuning-fork, even
if it makes only 39 or 41 instead of 40 revolutions per second, the
disturbance is shown instantly, because looking at the illuminated
tuning-fork one observes it jumping spasmodically. This movement
becomes more pronounced as the harmony between the revolutions of the
motor and the fork is disturbed, the jumps of the blade at times being
apparently of a very severe character. Moreover, curiously enough,
under the illumination of the ray of light the erratic movements of the
blade appear to be three or four times more severe than they really
are. But as the motor revolutions and the tuning-fork vibrations are
brought into synchrony, the movements grow quieter, until at last the
tuning-fork once more appears to be quiescent.

The explanation of this quasi-cinematographic illusion, which is as
interesting and as puzzling as that of the wheel, is very simple, for
it is based indeed upon the same phenomena. As the cardboard disk is
provided with two small holes spaced 180 degrees apart, the passage
of the ray of light is intercepted by the opaque section of the disk
80 times per second when the motor revolutions and the tuning-fork
vibrations are in absolute synchrony. The result is that at this speed
the light strikes the tuning-fork each time at the instant it is at the
half-way point in its oscillating travel. One hole in the disk comes
before the light when the blade has completed half its movement in one
direction, while the second hole comes into line with the light when
the blade is at the same point on its return journey. Consequently the
light falls upon the blade at the same spot every time, causing the
eye to imagine that it sees the blade always in the one position as
if under a steady ray of continuous light. Hence comes its apparent
quiescence. But directly the speed of the motor is altered in relation
to the vibration of the tuning-fork, the rays of light catch the blade
at varying points in its travel, and these changes, coming in quick
succession, convey the visual idea of movement. Acceleration of the
motor so that its revolving speed per second exceeds the number of the
tuning-fork vibrations, causes the perceptible movements to be made
more quickly, while on the other hand deceleration slows them down. In
reality the eye imagines that it sees more than what actually takes
place; it imagines that the blade of the fork is kicking spasmodically
and viciously, whereas in fact the extent of the movement to and fro is
constant and never changes.

While the experiment is peculiarly fascinating, its application is
extremely useful to the worker. It offers a means of being absolutely
certain about the speed at which the instrument utilised in a
particular investigation is running, so that the resulting calculations
may be completed without the slightest error.




CHAPTER IX

SLOWING DOWN RAPID MOVEMENTS


During the past few years much effort has been spent upon adapting
the cinematograph so that it will record exceedingly rapid movements,
such as a bullet in flight. Some popular films of this character
have been placed on the market, and, in order to attract the public,
have been colloquially described as "quicker-than-thought" or
"quicker-than-the-eye" movements. Strictly speaking both the latter
designations are erroneous, especially in regard to the eye, inasmuch
as if a bullet fired from a rifle were brilliant white the eye would be
able to follow its flight with ease, notwithstanding the fact that it
may issue from the muzzle with a travelling speed of 2,000 feet or more
per second.

So far as the moving-picture camera is concerned it is obvious that the
ordinary machine could not be operated with sufficient speed to film
a bullet in flight, or even to catch the flap of the wings of a small
insect, such as a house-fly or bee. It would be impossible to jerk
the film through the gate with sufficient speed to take perhaps five
thousand pictures per second--the mechanism, and more particularly the
film, would break down before a fiftieth of the number of pictures were
taken in the space of one second.

Accordingly, great ingenuity has been displayed by cinematograph
investigators in the evolution of a means of snapping such extremely
rapid movements at sufficient speed to make the films interesting
or scientifically useful. This particular branch of the craft was
developed first by Monsieur Lucien Bull, of the Marey Institute, who
designed a novel and ingenious camera capable of taking up to two
thousand pictures per second.[3] With this apparatus many wonderful
films have been obtained, and such a fascinating field of study has
been revealed that attempts are being made in all directions to secure
"quicker-than-thought" films that would have been thought ten years
ago to be photographically impossible. Monsieur Bull is developing
his idea in order to be in a position to obtain longer records of a
subject, and also to take the photographs at a higher rate of speed.
Professor Cranz, a German experimenter, also has carried out some novel
experiments on the same lines, and has designed a system whereby he is
able to take a photograph in the ten-millionth part of a second.

[3] See "Moving Pictures: How they are Made and Worked," Chapter XXIV.,
page 264.

This particular phase of cinematographic investigation is wonderfully
fascinating, and from the private worker's point of view it is
additionally attractive because it offers him an opportunity to
display his ingenuity. It is only by individual effort and the mutual
communication of ideas that perfection can be achieved, and in this
one field there is great scope. There are many problems which have
to be solved, many of which are peculiar to this particular study.
It involves a combination of the electrical and cinematographic
expert, since dependence has to be placed upon the electric spark for
illumination, and also upon electricity for operating the mechanism.

In such work as this the time factor is a most important feature.
Obviously, from the scientific point of view, it is essential to have
some reliable means of determining the fraction of a second in which
each picture is taken and also the period which elapses between the
successive pictures. In the system devised by Monsieur Lucien Bull a
tuning-fork is used. The vibrations of this fork per second are known,
and as the two ends of the fork are reproduced in each image, it is by
no means difficult to calculate the time factor.

Dr. E. J. Marey insisted strongly on the importance of this
registration of time. It is obviously essential in many kinds of
scientific work. Marey during his life investigated some very rapid
natural movements such as those of a pigeon's wings during flight.
Such a film would have been useless from the scientific point of view,
unless there were some means of showing in what interval of time each
successive picture was taken, and also the period which elapsed between
each exposure. Knowledge of these two facts enables one to tell the
time occupied in making a complete flap of the wing, and the physical
changes which take place in the shape of the wing to accommodate the
bird to different conditions, and it also enables the investigator to
trace the motion photographically lost while the lens is eclipsed to
permit the film to be moved forward.

To this end Marey devised an interesting type of clock. It consisted
of a dial provided with one large revolving hand which was driven by
ordinary clockwork. The face of the dial was marked off into twenty
equal divisions, each of which corresponded to one-twentieth part of
a second. This "chronoscope" as it was called, was placed near the
object under cinematographic study, so that both the movement of the
clock-hand and that of the object were photographed simultaneously.
This system of timing motions it may be pointed out has been revived in
a similar form by Mr. Frank Gilbreth in connection with "micro-motion"
study described in another chapter.

[Illustration:

 _By courtesy of the Marey Institute._

MAREY'S APPARATUS FOR TAKING MOVING-PICTURES OF RAPID
MOVEMENTS.

(For explanation see p. 112.)]

[Illustration:

 _By courtesy of the Marey Institute._

CINEMATOGRAPHING RAPID MOVEMENTS.

The complete beat of a pigeon's wing secured by Dr. Marey in eighteen
pictures, and taken, according to the "chronoscope" in the corner, in
3/20ths of a second.]

Marey also evolved a means of adapting the camera so as to enable
him to take the pictures at a speed exceeding sixteen per second. He
did not change the mechanism of the camera very radically, but was
able to secure as many as one hundred and ten pictures per second.
His arrangement of the camera was very simple, as shown on the plate
opposite. The film travelled intermittently, its arrest for each
exposure being very abrupt. In the camera were two cylinders C and
C^1 between which the film passed, and these cylinders revolved in
opposite directions and towards one another. As the two peripheries of
the cylinders were brought together the film was gripped and was moved
forward by friction, somewhat in the manner of the clutch-action which
was adopted in the very first moving-picture cameras. But each cylinder
was provided with eight flattened sections, of equal length, disposed
equidistantly. Consequently, when two opposing flat surfaces came
together the grip on the film was momentarily released, and the film
stopped, though the cylinders continued their rotary motion. By the
incorporation of gear trains the number of revolutions could be varied
up to about seventeen or eighteen per second. In the camera, above the
lens was a small device whereby the sudden and complete stoppage of
the film was assured during the periods when it was not gripped by the
cylinders below. Another similar device was introduced at F above the
window, through which the mechanism at the gate was visible, and this
also pressed lightly upon the film to counteract all the vibrations set
up from its quick intermittent movement. The unexposed film was mounted
upon a spool in the removable box R in the usual manner, but before
being fed into the camera it passed between two other friction disks
D and K, and was then fed through the camera mechanism and out at the
bottom into a second removable spool box L, where it was wound in after
exposure. This lower box also contained two friction disks similar to
those in the unexposed film box, and the larger of these cylinders in
the lower box, like D in the upper or unexposed box, was driven by the
revolving handle, through belts and pulleys.

It was a very simple apparatus. Although it was open to the objection
that the film might slip while photographs were being taken at high
speed, Marey proved strikingly successful in his use of it, his
pictures being wonderfully steady, even when taken at a speed of one
hundred and forty per second. In photographing the beat of a pigeon's
wings he secured a complete cycle of motion in eighteen pictures,
which, by reference to the chronoscope visible in the same field, shows
that they were recorded in three-twentieths of a second.

Such an adaptation of the camera could be used successfully to-day
for what might be described, somewhat paradoxically, as slow rapid
movements. But it would be better to secure a more positive and simple
means of moving the film forward. Of course the main advantage of the
friction disk system is that the film suffers no damage as it moves. In
an ordinary camera, working on the conventional claw principle, there
would be a tendency to tear the perforations when the pictures exceeded
sixty or so per second, and it would prove difficult in some instances
to ensure the absolute quiescence and steadiness of the film during
exposure. With the Geneva stop system of moving the film, a steady
smooth movement is more easily obtained than with the claw mounted upon
a sharp eccentric.

For such work where there is no desire to exceed two hundred pictures
or so per second, the ideal camera is that which has been perfected by
Monsieur M. P. Nogues, of the Marey Institute. In general appearance
this camera resembles the ordinary machine. It was designed specially
for the purpose of field work, for which Monsieur Bull's camera is
not suitable. In Monsieur Bull's camera the illumination is effected
by means of the electric spark, and it is impossible by this means to
light a large field.

[Illustration: Fig. 8.--Mechanism of the Nogues camera, wherewith up to
two hundred and forty pictures per second can be taken.]

In Monsieur Nogues' camera there are two claws, each mounted upon its
own eccentric, and the film passes between them. The claws do not work
together. That is to say, they do not engage the film simultaneously
on both sides, but work alternately. When one is engaged with the film
the other is in the out position. Without entering into a technical
description of the mechanism it may be stated that there is an
articulated lever system, so designed as to give the claws an irregular
D-shaped trajectory, which is very rapid and abrupt, the ascent of
the claw to re-engage with the film being sharper and quicker than
is possible in the orthodox design. The general design of the claw
mechanism and its method of operation may be gathered from a reference
to Fig. 8, wherein the paths described by the moving parts are
indicated clearly. The handle whereby the camera is operated is turned
at the normal speed of two revolutions per second, but this, owing to
the gearing, causes ninety or more downward jerks to be imparted to
the film F during each second. This makes one hundred and eighty film
movements by the two claws per second, and consequently one hundred and
eighty exposures.

Notwithstanding the high speed at which the celluloid ribbon is
moved through the camera, there are no signs whatever of tearing.
Furthermore, the film, during the brief period of exposure--from
1/360th to 1/480th part of a second--remains perfectly steady and quiet
in the gate.

The first camera built on this principle had a maximum speed of one
hundred and eighty pictures per second, but by modifying certain
details it was found possible to increase the velocity in a subsequent
machine to two hundred and two hundred and forty pictures per second.
This represents a far higher speed than has ever yet been attained
with the ordinary moving-picture apparatus. The machine is no larger
than the ordinary type, although, owing to the rapidity with which the
pictures are taken, the externally fitting film-box system is adopted,
so as to provide a supply of about 700 feet of film for exposure.

In projection on the screen the speed is reduced to about one-twentieth
or more of the rate of the exposure. The results are far superior
to any which have yet been seen upon the screen. The movements are
steadier and more continuous, inasmuch as the proportion of lost
movement is about one-twentieth of what it is with the orthodox
instrument. The result is that one sees upon the screen many phases of
movement which otherwise escape detection or are only partially shown
under present cinematographing conditions. Owing to the gearing and the
balance of the moving parts the operation of this camera is not more
fatiguing than that of the ordinary instrument; indeed, it runs far
more easily and lightly. The camera has been evolved for the express
purpose of reinvestigating many of the studies conducted by Marey,
which, owing to the imperfect appliances at his disposal, are possibly
incomplete.

But it may be asked, where is the demand for pictures taken at
such a speed? In reply it is only necessary to point out that such
photographing speeds are indispensable in studying the motions of
the smaller members of the animal kingdom. For instance, an amateur
recently prepared a film showing the life and habits of lizards. They
were taken at the normal speed of sixteen pictures per second, which
the operator judged to be sufficient. But when the pictures were shown
upon the screen, the very motions which are the most interesting, such
as the movement of the tongue, jerk of the head, and so forth, were
lost. Similarly, another film depicted the chameleon, but failed to
catch the instantaneous throw of its tongue. On the other hand, when
the pictures were taken at the accelerated speed of fifty to eighty per
second, the results were strikingly different. Not only were they more
complete, but they were smoother, more continuous, and more natural; in
fact, they were practically identical with those which the human eye
observes in the creatures themselves.

Phases of natural movement, capable of being recorded at speeds ranging
between eighty and two hundred per second, are the most promising
spheres of moving-picture activity at the present moment. Nature study
never fails to arouse enthusiasm, while from the operator's point of
view it is indescribably fascinating. Something unexpected is secured
at every turn of the handle. The portrayal of Nature stirs the emotions
of wonder, it is true to fact, and it often introduces the spectator
to something about which he has read but which he never has seen.
Consequently, so far as life is concerned, the pictures should never be
taken at less than forty to fifty per second, unless one is contented
to have a mere distorted impression of what actually takes place. Even
moving-pictures of the snail or tortoise, generally considered to move
very slowly, should never be photographed at a less speed, because
these have actions which cannot be caught at sixteen pictures per
second.

Generally speaking, the smaller the live subject under investigation,
the more rapid should be the photographing speed. The movements of a
bee's wings cannot be caught at sixteen or even two hundred pictures
per second. This was proved some time ago when Monsieur Lucien Bull,
by the aid of his electric spark system, and special camera, obtained
a series of photos showing how a bee regains its normal balance when
it is upset. For this purpose a bee was launched from the special
apparatus used in connection with the camera, with its equilibrium very
seriously disturbed. So rapid was its recovery that twenty pictures
taken in succession at the above speed served to illustrate the whole
operation, the final photograph showing the bee in normal flight.
This was the first occasion wherein this peculiar phenomenon had been
photographically recorded, and the unique character of the achievement
may be realised from the fact that the bee regained its balance in the
infinitesimal period of approximately the hundredth part of a second.

Even in photographing a man, to show rapid walking motion, a speed of
sixteen pictures per second is far from adequate. If he happens to
be walking at four miles an hour quite 75 per cent. of the motion is
lost, and the movement portrayed under these conditions is spasmodic
and jerky. For a natural cinematographic record of a man walking, at
the present orthodox rate of sixteen pictures per second, his pace
should not exceed a mile an hour. Therefore to film a man walking at
four miles an hour the photographing speed should not be less than
sixty-four pictures per second.

Though the ultra-rapid movement involves the use of intricate
electrical apparatus, it is a peculiarly absorbing study. The
appliances required are necessarily expensive, but, since it is
virtually an untouched province, enormous opportunities await the
patient worker. It is additionally attractive because each worker is to
a very great extent dependent upon his own ingenuity in the design of
efficient auxiliaries and secondary apparatus. It is this wide scope
for individual initiative which causes rapid cinematography to be so
keenly appreciated by investigators, and, as results have shown, their
discoveries when popularised make a very deep impression on the public.

Of course, in projection, it is useless to attempt to throw the
successive pictures upon the screen at anything approaching the speed
at which they were snapped. If the flight of a bullet recorded at say
ten thousand images per second, were projected at a corresponding
speed, nothing would be seen. So, in projection, the speed is slowed
down; the subject photographed at two thousand pictures per second is
thrown upon the screen and brought to the eye at the rate of sixteen
pictures per second. The bullet moves across the screen with the pace
of a snail. The wings of a dragon fly, which in life make several
hundred oscillations per second, appear to move as sluggishly as those
of a barn-door fowl. But the detail and the complex movements are
recorded; the eye sees and follows something which has formerly been
beyond its powers.

If it is desired to reduce the speed to its absolute slowest point, so
as to facilitate even closer study, the operator can take advantage,
to an extreme degree, of the phenomenon of the persistence of vision.
This has been done by Monsieur Lucien Bull. It is impossible to reduce
the speed of projection to less than sixteen pictures per second, for
this is the lowest rate at which the laws of persistence will allow
of an appearance of continuous motion. Yet there is an ingenious way
of obtaining the equivalent of a speed of eight pictures per second,
and this without either disturbing the apparently lifelike movement
or producing any flicker. The method is by duplicating each separate
picture of the negative upon the positive. That is to say each negative
picture is printed twice in succession upon the positive, so that 12
inches of film, which normally would carry sixteen successive and
different pictures carries in this case only eight. When projected upon
the screen, at the rate of sixteen pictures per second, the eye fails
to detect that it is seeing every picture twice. This might almost be
described as an optical illusion, and it makes another interesting
proof that the eye can be deluded by cinematography. Monsieur Bull,
after having found that the eye did not observe that two identical
pictures were shown in succession, endeavoured to carry multiplication
still farther. He found, however, that a pair of pictures was the
limit. When three identical pictures were shown in succession the
impression upon the eye was too long. The movement from triplet to
triplet gave a disjointed effect such as arises in ordinary projection
when the speed is too slow.




CHAPTER X

SPEEDING-UP SLOW MOVEMENTS


The preceding chapter described how it is possible to photograph
extraordinarily rapid movements and to slow down in projection so as
to enable the eye to follow them. Now I will go to the other extreme
and show how the very slowest movements can be accelerated and thrown
upon the screen in continuous motion. This feature has proved one of
the most popular in the whole range of cinematography, for it has
enabled the public to follow, within the course of a few minutes, such
wonderful and apparently impossible studies as the growth of a plant
from the germination of the seed and the appearance of the leaves
to the bursting of the bloom and the formation of the seed for the
propagation of the species.

The speeding-up of relatively slow movements has become a favourite
branch of research among cinematograph workers mainly because it is
simple, inexpensive, and comparatively easy. The worker needs to
develop only one special faculty. That is patience, for the recording
of a single subject may easily extend over a period of a month or so,
and the camera has to be kept going night and day to produce a faithful
record. It is a field which the amateur can follow very profitably. It
puts no great tax on his skill. The risk of failure is slight, and the
films thus obtained, if worked out upon popular or instructive lines,
are certain to command a ready market.

For this work one may use the ordinary L5 ($25) camera. It illustrates
the fact that cinematography is nothing more nor less than a string of
successive snap-shots, for the principle is that which is generally
described as "one turn one picture." That is to say, instead of the
handle being turned continuously as in taking a topical subject, it is
moved at stated intervals, and only sufficiently to make one exposure
and to jerk the film downwards the required distance ready to receive
the succeeding image. It virtually resolves cinematography into
ordinary snap-shot or Kodak photography.

This development, like many others widely practised in the
moving-picture world to-day, has issued from the Marey Institute.
It was there exploited in the usual manner for the study of natural
movement and phenomena. In the early days of the present century,
even before the picture palace came into vogue, the workers of this
institution produced a short length of film showing the opening of the
blossom of a convolvulus. Although this film is some ten years old it
would be difficult even now to improve upon it. The opening movement of
the petals is so steady and perfect as to suggest that the exposure was
not intermittent but continuous.

In these particular studies success in the main depends upon the
apparatus employed for the periodical exposure of the film and the
judgment shown in deciding the lapse of time between the successive
exposures. Naturally this varies according to the characteristics of
the subject under investigation. A mushroom, for instance, demands
exposure at briefer intervals than would be necessary for filming the
growth of a grain of wheat. The timing is perhaps the most difficult
part of the undertaking, because if it is not gauged to a nicety the
movement on the screen is apt to be unnatural, the growth taking place
in a series of sudden jerks instead of proceeding slowly, steadily and
gracefully. Many a first-class film of this character has been ruined
because the interval between the exposures has been too long to bring
about the necessary blending together of the motions in the successive
pictures. No hard and fast rule can be laid down to guide the worker.
Experience and close study of the subject being photographed can alone
enable this factor to be determined.

The auxiliary apparatus to ensure the exposures being made at regular
intervals need not be of an intricate character. The simpler the means,
the more likely is the result to be successful. Clockwork mechanism can
be devised to open the shutter at stated intervals, but this system
suffers from one serious disadvantage. The mechanism must be wound
up regularly, and when a long study is in progress, extending over a
fortnight or a month, the worker is apt to overlook this indispensable
duty. There is one worker who generally uses a water motor, and has
found it very reliable; but it cannot be safely left, and it ceases to
act if the public water supply be cut off.

The most reliable agent for such work is electricity. When the Marey
Institute first embarked upon these tedious subjects a very elaborate
apparatus was employed. It was like a gallows, being in reality a
massive wooden frame (see illustration facing page 128) fitted with a
pulley. A rope passed over this pulley, and to one end was attached
a weight P. The other end passed round a small winch T, to which the
camera C was connected. Upon the spindle connecting these two parts
of the mechanism was a small wing-piece L, one of the extremities of
which rested upon a vertical spindle E connected with an electro-magnet
F. In the electro-magnet circuit was a small water-balancer B having
two cells and a see-saw motion. This was driven by a stream of water
flowing from the tap of the tank R. The flow of water from the tap
could be regulated.

When the elevated cell of the balancer was filled, its weight caused
it to fall. As it fell the electric circuit of the battery V was
closed. This caused the small vertical rod E to be drawn downwards by
the electro-magnet F. The descent of the rod allowed the leaf L to
fall. The make and break in the electro-magnet was instantaneous, so
that the vertical rod E immediately returned to its normal position,
with the result that, when the wing came round, after completing a
revolution, it was stopped, and remained there until the second cell
of the water-balancer, filling and falling in its turn, repeated the
cycle of operations. As the rod carrying the wing L was the common axis
of the winch and the driving mechanism of the camera the release of
the wing brought the strain of the weight P upon the cord, and thereby
moved the camera driving mechanism a complete revolution. Thus it
conformed to the "one-turn-one-picture" movement. It was a combination
of weight-driven and electrical mechanism, and, though apparently
complicated and certainly cumbersome, it was satisfactory because it
completed its work with unerring steadiness and regularity. As the
weight P descended a very small distance for each exposure a single
winding-up was sufficient to drive the mechanism for several hours. The
intervals between the exposures could be varied by turning the tap on
or off, thereby changing the volume of water flowing into the balancer.
The thinner the water stream the longer the period required to fill the
cell, the longer the interval between each see-saw, and obviously the
greater the lapse of time between each exposure. Similarly the time
intervals between each exposure could be shortened by turning on the
tap so that the cell became filled more quickly.

[Illustration:

 _By courtesy of the Marey Institute._

THE ELABORATE APPARATUS CONTRIVED AT THE MAREY INSTITUTE TO TAKE
THE FIRST MOVING-PICTURES OF THE OPENING OF A FLOWER.

(For explanation see p. 127.)]

[Illustration: THE FIRST MOTION-PICTURES OF AN OPENING FLOWER.

Taken at the Marey Institute. The complete opening of a convolvulus is
shown in fifteen pictures.]

[Illustration:

 _By courtesy of the Marey Institute._

THE DEVELOPMENT OF A COLONY OF MARINE ORGANISMS.

(Read from top to bottom and left to right.)]

In the Marey Institute investigations with the convolvulus, which was
placed on a chair a short distance from the lens of the camera, sixteen
successive snap-shots were made in the hour. These pictures, taken at
intervals of four minutes, show the complete opening of the flower,
the phases in the successive pictures blending so well together as to
convey the impression that the pictures were taken at the normal speed.

A striking contrast to the bulky, weighty, and massive apparatus
employed ten years ago to photograph intermittently the opening of a
flower is the latest device which is employed at this Institute for
this work. It is a small, light compact contrivance driven by a kind
of carriage clock. This clock actuates two levers whereby electric
contacts are made at predetermined intervals to open and close the
lens. This mechanism can be set so as to give exposures at intervals
ranging from a minute to several hours, and will run for twenty-four
hours without attention. The apparatus is as accurate as it is
ingenious.

It is obvious, however, in such work, that a great deal depends upon
the personality of the worker himself. If he is skilful he will find no
difficulty in devising a reliable timing apparatus which he can trust
for hours together. But the simpler the character of the appliances the
more trustworthy will they prove, because the reduction in the number
of the component parts will decrease their liability to derangement and
irregular action.

Seeing that exposures have to be continued at the predetermined
intervals throughout the whole twenty-four hours, arrangements
must be made for artificial illumination during the night. This
should not prove a difficult problem. There is a wide range of
illuminants--electricity, gas, acetylene, etc.--from which a choice
can be made according to the circumstances of the case. Thus a worker
living in country districts may find a difficulty in obtaining electric
current or coal gas, in which case he must rely upon acetylene, or a
petrol gas flame, in conjunction with an incandescent mantle, or even
an electric battery and flash-lamp with a reflector.

If electricity or coal gas are available from public supply sources
there need be no anxieties whatever. A metallic filament incandescent
electric lamp of high power is quite sufficient for the purpose, and
if there is need for a concentrated strong light it can be obtained by
mounting the lamp within a parabolic reflector, such as is used for
automobiles. Coal gas with an incandescent burner and mantle is just as
efficient, and concentration in this case can be managed in the same
way with a reflector. But it is necessary to make sure that no draughts
play upon the gas flame, as the intensity of the light might thus be
greatly impoverished.

Acetylene is a very useful and powerful illuminant when all else fails.
It is the nearest artificial approach to sunlight. Petrol gas with an
incandescent mantle will be found just as good as ordinary coal gas,
while there are many cheap lamps well adapted for its use. If all these
alternatives are lacking there is the electric flash lamp working with
the dry battery. A tiny metallic filament incandescent bulb mounted
within a parabolic reflector will give a light of intense brilliancy.
But the exhaustion of the battery causes the value of this light to
diminish in a relatively short time, so it is well not to let it burn
continuously. There should be a means of producing the flash only at
the moment the timing apparatus makes the exposure. In one application
of this system the flash and the movement of the shutter are controlled
by an electro-magnet, arranged in such a manner that the lamp lights
up a fraction of a second before the shutter is moved. Thus the object
under study is in the full glare of the light before the film is
exposed. Of course, if a high capacity accumulator can be obtained,
such as that of the latest Edison Nickel type, the light may be left
burning continuously. But when there is already an electrical system of
actuating the shutter it is a simple matter to incorporate a means of
limiting the contact in the lamp to the moment of the exposure.

For the average worker, however, the electrical system is too costly.
He will usually prefer a form of light which can be allowed to burn
continuously through the night. Even the longest night will not consume
a very great quantity of current or gas. Also, unless some very
accurate mechanism is used for controlling the intermittent operation
of the light, there is always a chance that the exposure and the
illumination may fail to synchronise, and thus an excellent film might
be ruined.

The "one-turn-one-picture" movement has to be adopted for many
subjects other than flowers. For instance, it is necessary in filming
the movements of the star-fish, in evolution phenomena such as the
emergence of a chicken from its shell, and in the case of certain
minute organisms which can be cinematographed only with the aid of a
microscope. But the same broad principles apply in each case; there
is equal need for time and patience, while complete success can only
be achieved by careful observation and ingenuity. There are critical
moments in such work and the unexpected frequently happens. Unless
the operator is equal to the emergency weeks of tedious labour may be
wasted.

The study of exceedingly slow movements offers a very promising field
to the patient worker. A film which occupies a month to photograph,
and entails an exposure once every thirty minutes, produces a film
only 90 feet in length. In projection it passes across the screen in
a minute and a half. This means that a process of Nature is condensed
into one thirty-seven-thousandth part of the time it actually took,
and its presentation on the screen is a remarkable triumph. But at
first sight the minute and a half seems a very slight return for the
time and labour expended. This is one of the principal reasons why
the professional cinematographer displays a marked aversion to the
recording of slow movements. On the other hand, it offers unique
attractions to the private investigator, for the time occupied in
preparing a film that reveals the wonders of Nature invariably commands
a high price if it has the elements of popularity or novelty.




CHAPTER XI

CONTINUOUS CINEMATOGRAPHIC RECORDS


It has already been pointed out that the intermittent method of taking
cinematograph pictures results in the loss of certain motions which
occur during the interval when the lens is eclipsed by the shutter.
A similar loss is experienced by the eye, in daily life, when it
blinks. In the case of blinking, of course, the proportion of movement
which escapes observation is exceedingly small. But in cinematography
practically one half of the movement is lost. When very rapid movements
are being investigated these losses become appreciable--in fact the
most vital part of a motion may be missed during the 1/32 part of a
second during which the lens is covered by the shutter.

There are many fields in which cinematography as at present practised
is quite useless owing to this intermittent eclipse of the lens.
Suppose that the behaviour of a rapidly moving piston rod is under
observation. With the ordinary type of moving picture camera and
process the results are quite misleading. The piston travels so
rapidly, perhaps at a rate of 8,000 lineal feet per minute, that with
sixteen pictures per second only a very small proportion of the work
would be recorded.

This deficiency, however, is remedied by another development in
chronophotography. This is the continuous cinematographic record,
the outstanding feature of which is the elimination of the revolving
shutter and the intermittent movement of the film, in favour of a lens
that is constantly open, a sensitized ribbon that moves steadily and
continuously all the time the experiment is in progress.

Marey, in the course of his momentous investigations with animated
photography, used this system for a number of experiments in which an
intermittent exposure would not have afforded sufficiently precise
results. Recent experiments have substantiated Marey's contentions upon
this point, and have shown how unreliable are the results obtained with
sixteen pictures per second where extraordinary precision is required.
An effort was made to remove the drawback of the intermittent method by
writing in, or divining, the movement which occurred during the periods
of eclipse, but this method, in turn, was found to be unreliable. There
are some motions which it is impossible to imagine or anticipate, even
if they do occur in the one-thirty-second or one-sixty-fourth part of a
second.

[Illustration:

 _By courtesy of the Marey Institute._

CONTINUOUS MOVING-PICTURE RECORDS OF THE BEATS AND SOUNDS OF THE
HEART.

Electro-cardiogramme of a normal person. The upper line refers to
the heart beats; the lower line is a photographic record of the
heart sounds. These wonderful pictures are rendered possible by Dr.
Einthoven's string galvanometer in conjunction with Mr. Lucien Bull's
ingenious camera.]

[Illustration:

 _By courtesy of the Marey Institute._

CONTINUOUS MOVING-PICTURES OF THE HEART BEATS OF AN EXCITED
PERSON.

The upper line shows the palpitations occurring at irregular intervals,
while the lower line is a cinematographic record of the heart sounds.]

Under these circumstances the continuous photographing system is now
very extensively employed. It has undergone many wonderful developments
and achieved extraordinary success.

One of the most interesting and marvellous of its triumphs was won
with the extremely sensitive "string" galvanometer, which was invented
by the eminent Dutch scientist, Professor Einthoven. This particular
apparatus has been of incalculable value to the medical profession, and
Monsieur Lucien Bull has constructed a special camera with the idea
of obtaining permanent and continuous cinematographic records of the
experiments conducted by means of it.

The apparatus employed for this particular sphere of operations is of a
somewhat involved character. Fundamentally the camera is that which was
designed by Monsieur Bull for photographing the flight of insects at
the rate of two thousand pictures per second, but it has been modified
to suit the new conditions. The reason why it offers the best chance of
securing a continuous record is that its sensitized ribbon is mounted
upon a drum, a single winding of which produces a photographic record
about 3 feet 6 inches in length.

The principle of the Einthoven string galvanometer may be described
roughly in a few words. There is a very fine conducting wire, or fibre,
of platinum or silvered quartz, which is stretched across the magnetic
field of the galvanometer. It is extremely thin, being virtually a
hair. Now, when an electric current, ever so slight, is transmitted
through this fibre, or string, as it is called by the inventor, it
is deflected from its position of rest, the extent of the deviation
varying with the strength of the electrical disturbance. When a slight
current is sent through the string it may betray the fact with no more
than a slight tremor, but a stronger current will cause it to move
violently.

A pencil of light, from an electric arc lamp, is transmitted through
the galvanometer in such a way that the string is brilliantly lighted.
An enlarged image of the string is then thrown upon the sensitized
ribbon in the camera by means of a powerful microscope lens.

Seeing that the time and distance measurements in such delicate
experiments as these are of the first importance, the sensitized
surface upon which the record is printed--paper or film--is calibrated
photographically while the experiment is proceeding. It is divided into
small squares, the longitudinal lines referring to the time factor,
while the transverse lines indicate the extent of the movement of the
quartz thread.

This continuous record system is of inestimable value in connection
with physiological researches when details concerning the beating
of the heart are desired. A person who places a finger of each hand
upon the extremities of the string, witnesses the recording of his
own heart beats. For the brief period between each beat the string
remains quiescent in its normal position, and the record of the
same, the enlarged shadow thrown by the pencil of light through the
microscope lens, is made upon the sensitized surface within the camera
in the form of a steady straight line. The beat of the heart sends an
impulse of electricity through the galvanometer, and causes the string
to deviate rapidly. As the pencil of light is shining continuously
through the microscope lens of the instrument, it stands to reason
that the slightest tremor of the thread, accentuated in the shadow,
must be recorded. No vibration is too slight to be caught. Not only
is the extent of the vibration photographed and capable of being
calculated by means of the calibration, but, as the sensitized ribbon
is travelling continuously past the lens, the duration of the vibration
is photographed as well.

In the case of a normal and healthy person the number of vibrations
on the record, corresponding to heart-beats, will average about 80
per minute, and their extent or amplitude will remain comparatively
even. But if the person is in bad health, excited, or exhausted,
the palpitations will be depicted in the most erratic manner, both
as regards their occurrence and their force. One very powerful
palpitation, for instance, may be followed by a comparatively long
interval of quiescence, succeeded by several spasmodic short movements
at brief unequal periods.

From the medical point of view the perfection of the system offers
illimitable opportunities. In the hospital, where a patient may be
lying in a critical condition, the surgeon can have a continuous record
of the state of his pulse without its being felt by hand at intervals.
The physician, in unusual or baffling cases of disease, can have a
photographic record of the pulse and heart movements from the moment
the symptoms develop until the patient either dies or recovers. It
also enables the physician to be informed as to how the invalid is
responding to his treatment. Hitherto, the practice has been to feel
the pulse at varying specified intervals, to commit the readings to
a chart, and then to connect the points by lines so as to show at a
glance whether heart movement has accelerated or decelerated, and to
what degree. Such charts are satisfactory so far as they go, but they
may be erroneous, because the action of the heart may have fluctuated
between the readings. With the continuous photographic system,
however, guesswork does not enter into the issue at all. The complete
story is set down in an unimpeachable graphic manner.

Perhaps the most extraordinary feature of this development is that the
very sounds of the heart palpitations can be committed to a sensitized
surface in a continuous manner. The principle is much the same as in
the case of the record of the heart's movements. There is a small light
disk provided with an aperture, mounted upon a stand. Across this
aperture is stretched a thread of platinum or quartz. This instrument
is placed in the horizontal path of a pencil of light, between the
camera and the source of illumination, so that the ray passes through
the aperture of the disk to enter the lens of the camera. Consequently
the shadow of the quartz thread is thrown upon the sensitized surface
in the camera.

A film of soapy water is spread over the aperture in the disk, and
this, of course, comes into contact with the quartz thread. The
provision of this film in reality converts the disk into a very
sensitive diaphragm. Now a stethoscope is placed over the patient's
heart, the opposite end of which is connected to the disk in such a way
as to bear upon the surface of the soap bubble. When the heart beats
the noise which is set up thereby is received by the stethoscope and
conveyed to the soap bubble. The bubble, being very sensitive, responds
to the sound movement in greater or less degree. As it vibrates, it
naturally moves the quartz thread with it, and the moving shadow of the
string is caught by the photographic film in the camera.

In this manner the surgeon or observer can have a permanent continuous
record of the sound of the heart beats converted into movement, and
from the regularity of the oscillations he is able to tell whether
the heart is beating regularly. If desired, the record of both the
heart-beat as demonstrated by the galvanometer, and the sound of the
palpitation as indicated by the soap bubble diaphragm, may be obtained
upon one chart, and, in synchrony, so as to set a double check upon the
observations.

The chronophotography of continuous movement has been brought to a
high stage of perfection by the searching experiments of Professor
Einthoven. From the physiological point of view he has contributed
most valuable data concerning the heart, for his experiments have
been with subjects of all ages and in varying conditions of health.
The investigations have been extended to animals also, showing the
differences in heart beating phenomena between the various members of
the animal kingdom.

[Illustration:

 _By courtesy of the Marey Institute._

CONTINUOUS CINEMATOGRAPHY.--THE PALPITATIONS OF A RABBIT'S
HEART.

The vertical lines indicate the extent of the heart beat, while the
horizontal lines give the time interval.]

[Illustration: THE STEREO-MOTION ORBIT OF A MACHINIST'S HAND.

LINES OF LIGHT INDICATING TO-AND-FRO HAND MOVEMENTS.

The latest development in Micro-motion Study. A small electric
incandescent lamp is attached to the workman's hand, and the lines of
light photographed.]

There is an increasing tendency to adopt continuous cinematography
in preference to the intermittent motion for many other phases of
particular study, especially where very fine results are desired.
One mechanical engineer has applied the method to the measurement of
the deflection of bridges when undergoing tests. Monsieur Deslandres
adopted a combination of stylography and chronophotography for
recording the vibrations in metal bridges under varying conditions of
traffic as far back as 1892, but the direct cinematograph record is
to be preferred. Sometimes a camera has been used in combination with
the existing processes of observations, so that a photograph of the
actual movement and of its extent is obtained simultaneously, while the
calibration of the sensitized surface, or the introduction of a clock,
like that used by Marey, enables the time intervals to be accurately
determined.

Another ingenious form of continuous record, which was made many years
ago by Soret and Georges Demeny, the collaborator of Marey, has been
revived in an improved form by Mr. Frank B. Gilbreth, the eminent
American authority on motion study. In this case a moving film is
not absolutely essential, but under certain conditions it is to be
preferred. The object of the study is the tracing of motions with
a view to their improvement and expedition, or the elimination of
unnecessary actions, so that the particular task may be achieved in
less time and with reduced exertion.

A stationary plate may be used, and the path of the motion is indicated
by a ribbon of light from a small electric incandescent lamp which is
attached to the hand or other limb of the subject. In this instance
the plate presents an apparent jumble of lines, but by the aid of a
magnifying glass the complete cycle of movements can be followed from
end to end. When the photographs are taken upon a stationary plate,
however, it is necessary that they should be taken stereoscopically,
so that relief may be given to the picture to enable the movement
to be followed correctly. The hand or limb may not be visible in
the photograph, but that is a minor detail, because the path it has
described is indicated by the lines of light. When the subject is
continually advancing, where it does not double back upon itself, a
slowly moving film will supply a complete and perfect graphic record of
its progress. But in all such experiments the timing element must be
incorporated, or the record will have little practical value, and will
provide no conclusive evidence.

A novel application of this method was carried out by Demeny several
years ago. The scope of the investigation was the study of the
characteristic walks and gaits incidental to certain maladies. Patients
suffering from rheumatism and other complaints which interfere with the
natural walking motions were taken into a darkened room. Incandescent
electric lights were attached to their shoulders, heads, and other
parts of their bodies, and these were photographed as the subjects
moved about the darkened room. The results upon the sensitized surface
were merely the paths described by the moving lights. There have been
many applications of the continuous record, especially to the work of
testing physical, chemical, or electrical phenomena. The observer is
certain to obtain a correct result. This has been shown in certain
microscopical observations where the movements are extremely rapid, and
where a graphic outline is more important than the photographic detail
of the subject.

The great advantage of the continuous cinematographic system is that
it records every movement. Even the slightest vibrations will be
indicated, and upon a large or small scale according to the rapidity
with which the travelling sensitized surface is moved through the
camera. Comparative investigation between this and the other systems
has proved that the continuous cinematograph shows many motions which
the former systems lose. It has introduced the investigator to many
curious phenomena of which he was previously ignorant.

One thing must be emphasised. It is the salient difference between
the ordinary cinematographic method and the continuously moving
film process. The first records upon the film a complete picture
of the subject. The second records only the path or trajectory of
a _single point_, or at the utmost of a number of points, of the
subject under observation. This remark does not refer to the method of
cinematographing with the electric spark, which is a totally different
and special application of the art.




CHAPTER XII

RADIO-CINEMATOGRAPHY: HOW THE X-RAYS ARE USED IN CONJUNCTION WITH THE
MOVING-PICTURE CAMERA


With the perfection of radio-photography it was not surprising that the
cinematograph investigator pressed this new development into service.
It opened up a wide and fascinating field for moving pictures. When the
Roentgen rays were first introduced there was one serious handicap to
photography by their means--the length of the exposure. But the chemist
and the scientist speedily removed this adverse factor, and now X-ray
photographs can be taken instantaneously--60 per minute.

Long before this achievement Radio-photography had been yoked with the
moving pictures. It was a difficult problem, but it was solved. One
scientific inventor stands out prominently in this connection. This
is Monsieur M. J. Carvallo who, during his position as sub-director
and secretary of the Marey Institute, spared no effort to harness
the X-rays to cinematography. Another illustrious worker is Dr. J.
Comandon, who may be said to be the pioneer of the popularisation of
cinematographic science. It was he who first appealed to the public
with films of this character under the auspices of the well-known firm
of Pathe Freres. He has been responsible for the preparation of many
most interesting films. Both of these workers have shown what can be
achieved in this direction, while the fact that they proceed upon
totally different lines adds value to their work. It enables their
followers to decide for themselves which principle is likely to produce
the most satisfactory result in each case.

Strictly speaking, Monsieur Carvallo's methods would appeal more
strongly to the scientific mind, bent upon the discovery of some
abstruse phenomena, and indifferent to the complicated process
involved. The methods of Dr. Comandon, on the other hand, from their
enhanced simplicity, will attract the average worker. This investigator
makes a special point of accomplishing his end in as simple a manner as
possible.

From this it will be judged that radio-cinematography may be expensive
or inexpensive. This is a correct assumption, but the amateur
investigator need not fear that the deeper researches are beyond his
reach. In justice to Monsieur Carvallo, it must be mentioned that his
experiments were undertaken at a time when radio-photography had not
reached its present stage, and therefore he had to contend with certain
difficulties which no longer exist.

[Illustration:

 _By courtesy of the Marey Institute._

A WONDERFUL X-RAY FILM MADE BY M. J. CARVALLO.

The process of digestion in the intestine of a frog after its removal
from the body.]

[Illustration:

 _By courtesy of the Marey Institute._

MOVING X-RAY PICTURES OF THE DIGESTION OF A FOWL.

These pictures, taken at five per second by M. J. Carvallo, show the
different phases in a complete cycle of the gizzard, which lasts
exactly five seconds.]

Monsieur Carvallo was probably the first worker to attempt to portray
in movement the elusive and peculiar features revealed by the Roentgen
rays. One or two other scientists had dabbled in the art, but their
achievements were not very convincing for the simple reason that they
did not employ chronophotography. Monsieur Carvallo, however, being
fully aware of the valuable work that had been carried out by Dr. E. J.
Marey, saw the true way of applying radiography to cinematography, and
saw that it could not fail to be of scientific value. He embarked upon
a number of illuminating, though tedious, experiments, in the effort to
combine these two branches of photography.

Carvallo's installation was of a most elaborate character, but he
accomplished some marvellous results, the full significance of which
are appreciated only to-day. The complete apparatus he used in his
experiments is shown in Fig. 9. The source of energy was a small
electric motor, capable of making 2,000 revolutions per minute with a
current of only 50 volts. This motor was extremely sensitive, since it
would make 300 revolutions per minute with a current of 10 volts. The
control of the speed was essential to his work, so he elaborated a
simple and ingenious change-speed gear mechanism, which enabled him to
drive the camera at four different speeds without touching the motor.
The gear mechanism was not dissimilar from that adopted upon a larger
scale in automobiles, lathes, and other machinery where the speed has
to be varied according to the character of the work. The direct drive
was transmitted from the motor-shaft to that of the camera mechanism
through a belt and pulleys so as to secure flexibility and immunity
from shocks. The three lower speeds were transmitted through gear
wheels. These sets of wheels were mounted upon two parallel shafts and
worked upon the sliding principle, which was found to be the simplest
and most effective. In order to reduce the noise arising from the
meshing and working of the gears the smaller wheels were made of fibre.

[Illustration: Fig. 9.--The ingenious radio-cinematographic apparatus
devised by Monsieur M. J. Carvallo.

A.A. Film spools. B. Crookes tube. C. Frog being radiographed. D. Coil.
=F=. Film. F. Clock. G. Exposure interrupter. H. Change-speed
gears.]

By this gearing system it was possible to vary the speed of the camera
from 30 revolutions per second to one turn in 15 seconds. When still
slower speeds were desired, upon the one-turn-one-picture principle,
the motor was cut in and cut out intermittently so that the exposure
could be varied from once in 20 seconds to once in an hour or more.
Of course, in those instances where the exposures only needed to be
made at relatively prolonged intervals, the driving motor was started
up intermittently so as to move the shutter at the required moment. A
pendulum clock was introduced into the electrical circuit, together
with a novel relay. The clock-face was provided with a ring around
the dial, with the hour intervals represented by contacts instead of
figures. The clock was fitted with one hand only. One electrical lead
was connected to the contact ring and the other to the pivoted end of
the clock-hand. When the latter came against one of the contacts the
electrical circuit was completed, the motor was set in motion, and the
camera mechanism was given one turn--sufficient to make an exposure
and to jerk the film forward the desired distance through the gate for
the next exposure. Obviously this clock system is capable of variation
as desired. The contacts may be disposed to coincide with intervals of
a second, a minute, an hour, or more between successive exposures. It
was necessary to ensure that the contact was of sufficient duration
to complete the cycle of camera movements, and, on the other hand,
to prevent the motor movement being so prolonged that more than the
requisite exposure and movement of the film would be made. This was
effected by means of a brake, which arrested the movement of the motor
after the exposure had been completed.

[Illustration:

  I.      II.      III.

  _By courtesy of the Marey Institute._

RADIO MOVING-PICTURES OF COLD-BLOODED ANIMALS MADE BY M. J.
CARVALLO.

I. The stomach and the intestine of a trout (one exposure every 20
seconds). II. The digestive organs of the frog (one exposure every
2 seconds). III. Lizard digesting its food (one exposure every 90
seconds).]

[Illustration:

  1.      2.

  _By permission of Pathe Freres._

TWO OF DR. J. COMANDON'S EARLIEST INVESTIGATIONS IN
RADIO-CINEMATOGRAPHY.

1. X-ray moving-pictures of the bending of the knee, showing muscular
movement. 2. X-ray film of the opening of the hand.]

With this seemingly complicated apparatus it was possible to take any
desired number of successive pictures and at any intervals of time with
unerring precision.

For these particular experiments a special film was prepared, for
the pictures produced by the standard camera were not large enough.
Monsieur Carvallo took pictures of a depth of 2-2/5 inches instead
of the usual 3/4 inch. Special arrangements were made also to secure
extreme sensitiveness of the emulsion so that it might be more
susceptible to the action of the X-rays. The disposition of the film
followed special lines, as may be seen by reference to the diagram
(Fig. 9). The Crookes tube, containing the X-rays, was placed beneath
a table provided with an aperture upon which was laid a transparent
medium, such as glass, to support the subject under investigation.
Above this was placed the gate through which the film was moved
intermittently, the sensitized ribbon travelling in a horizontal
direction from one spool to the other. In the early experiments a
Maltese cross movement was incorporated to provide the requisite
intermittent motion to the film, but subsequently a novel claw motion
devised by Monsieur Nogues, the mechanician to the Marey Institute, was
introduced with far better results.

In carrying out the experiments with different live subjects extreme
ingenuity was used in placing and holding the creature so that the
most perfect images might be obtained. Monsieur Carvallo devoted his
energies largely to radio-cinematographing the functions of digestion,
and selected such subjects as fresh-water fish, toads, frogs, lizards,
birds, and mice. Thus he obtained comparative results from five species
of the animal kingdom. The subjects were fed first with a special diet,
comprising a mixture of flour, sugar, peptone, sub-nitrate of bismuth,
and water or milk. The chemical, sub-nitrate of bismuth, was used in
order to give the alimentary canal the necessary opacity to secure
the best results under the Roentgen rays. In the case of the trout the
chemical was injected into the blood.

In order to obtain sharp, clear, and distinct pictures upon the film,
the subject under study had to be fixed in an immovable position. In
the case of a trout a small celluloid envelope was made, fitted at
each end with a small glass tube through which water necessary to the
fish's existence was passed in a continuous stream. This vessel was
only just large enough to contain the fish, so that movement was quite
impossible. The top of the vessel was closed with a sheet of paraffin
paper, which was placed in front of the aperture of the film gate. It
was a very novel and successful means of radio-cinematographing a fish
under natural conditions. The fish themselves appeared to suffer no
ill-effects from the method adopted to keep them alive, a trout in one
instance being kept in this confined position for two consecutive days.
So long as an adequate supply of fresh water was passed through the
celluloid vessel in which it was encased it experienced no trouble in
respiration.

In the case of the toad and frog the subject was kept in a prone
position by attaching thin ribbons to the legs and extending the latter
to their utmost so that the digestive organs might be radiographed
clearly, distinctly, and without difficulty. The lizard, which is very
difficult to photograph, was secured in a similar manner. The birds
likewise were attached by their legs, and had their wings extended so
that the body came directly in the path of the rays. When young birds
were under investigation it was necessary to maintain a circulation of
warm water around their bodies so that the temperature might remain
constant; otherwise the digestive functions might have been disturbed,
thereby invalidating the value of the pictures. In one investigation a
fowl was placed in a plaster cast so as to hold it perfectly still and
steady.

The photographic speed was varied according to the character of the
investigation and the subject. Thus, in recording the digestion in
the stomach and intestine of the trout, an exposure was made every
twenty seconds. In the case of the toad the speed was one in every ten
seconds, while the chicken required one in every five.

One of the most novel experiments which Monsieur Carvallo carried out
in this particular field was to ascertain the extent to which digestion
will continue in the intestine after it is removed from the animal. The
digestive tube of the frog was selected for this novel investigation
and the photographs taken at the rate of one per second illustrate the
fact that the digestive organ will continue its functions long after
its removal from the body.

Since the year 1900 when Monsieur Carvallo carried out his scientific
researches with the Roentgen rays, radiographic science has made great
strides. Researches of this character no longer require elaborate
and expensive apparatus. This has been shown by Dr. J. Comandon, the
well-known French scientist, who, at the laboratories of Messrs. Pathe
Freres, has prepared some magnificent X-ray films in such a manner as
to make them interesting to the average patron of the picture palace.
Dr. Comandon possesses the unique ability of so treating his subject
as to make it appeal to the unscientific mind.

[Illustration: Fig. 10.--Dr. Comandon's radio-cinematographic
apparatus.]

In his system Dr. Comandon does not radio-cinematograph directly in
the manner of Monsieur Carvallo, but has recourse to the fluorescent
screen, thereby obtaining his results much more simply and easily. By
this means, also, he is able to use the standard cinematograph camera
and film without any modifications, the images upon the sensitized
celluloid ribbon being of the normal size. The general arrangement
of the apparatus used by this investigator is shown in the diagram
(Fig. 10). A room is divided by a partition A. On one side is placed
a camera F of the conventional type. On the other is the necessary
electrical apparatus. An aperture B is provided in the partition,
and this space is filled with a fluorescent screen. On one side of
the partition A centrally in regard to the fluorescent screen, and a
little distance therefrom, is placed the Crookes tube C, the subject
under investigation being placed between the tube and the screen.
Consequently, the radiograph is projected upon the fluorescent screen
and this image is then photographed by the camera. At the normal
photographing speed the exposure is about 1/32 second.

The fluorescent screen employed by Dr. Comandon is of the type known
as "reinforced." It is covered with tungstate of calcium, instead
of barium platino-cyanide. With this screen the Roentgen rays are
intensified, or rather are transformed, the luminous radiation being
rendered more actinic and therefore able to act more quickly upon the
emulsion of bromide of silver with which the film is coated. By using
this fluorescent screen the exposure is reduced to about one-tenth of
what would be required were the subject radiographed direct.

The high tension current is supplied from an apparatus of a special
type E with which a current as high as 100,000 volts can be obtained.
Another prominent feature is the high tension interrupter D, which cuts
the electric circuit of the tube in and out, in synchrony with the
camera mechanism. Thus the Crookes tube is active while the shutter is
open but inactive while it is closed.

This interrupter consists of a small glass vessel, charged with petrol,
and sealed with a cover of insulating material. Within the vessel, and
spaced about 2 inches apart, are two brackets, which extend through
the sides of the receptacle through hermetically sealed joints. To
these brackets the positive and negative wires are coupled. Above
the brackets, and moving within the vessel, is an inverted U-shaped
piece. This slides up and down through apertures provided for the
purpose in the insulated cover. When lowered to its full extent the
arms rest upon the brackets, to which the wires are attached, and
this contact completes the electrical circuit. A pulley wire is fixed
to the centre of the inverted U-piece to allow it to be moved up and
down as required. The up-and-down movement serves as a make-and-break
for the circuit. A lift of a quarter of an inch suffices to break the
circuit, which lift is effected by the mechanism of the camera over a
system of cords and pulleys. Thus, when the camera handle is turned
to open the shutter, the contact piece in the interrupter is lowered,
the circuit is completed, and the Crookes tube is brought into use.
Directly the shutter is closed the contact piece is raised and the tube
is disconnected. This simple control permits the exposure to be varied
from five or six to sixteen exposures per second, while the tube can
be kept continuously at work for as many as fifty-five seconds if
desired.

The camera is fitted with a lens made from quartz, which permits the
maximum quantity of the actinic rays to pass through to the sensitized
film. The film is covered with an exceptionally sensitive emulsion in
order to ensure the best results possible with very short exposures.
In order to protect the spools of film in the camera from the actinic
properties of the rays diffused from the fluorescent screen, the boxes
are covered with sheet lead, while the operator is protected with a
lead apron, such as is used generally in Roentgen ray investigations.

The many interesting films which Dr. Comandon has produced offer
adequate testimony to the practicability and success of the system
which he has evolved. Undoubtedly it is the simplest and most
inexpensive method of "radio-cinematography" which has been brought
into practical operation up to the present, and it is one which may be
followed by the private investigator with such modifications as may
suggest themselves in particular cases.




CHAPTER XIII

COMBINING THE MICROSCOPE AND THE ULTRA-MICROSCOPE WITH THE
MOVING-PICTURE CAMERA


One of the most fascinating fields in the whole realm of animated
photography is the filming of the infinitely small by the aid of
the microscope. In this manner it is possible to catch glimpses of
bacterial and microbic life in natural movement, and to throw them
upon the screen, where the extreme magnification enables one to follow
with ease the motions of a living world invisible to the naked eye.
Furthermore, the representation upon the screen is clearer, brighter,
more detailed, and easier to follow, than any image seen directly
through the microscope. There is an absence of that distortion and
unnatural motion which often occur when the microscope alone is used.

Micro-cinematography may be either costly or cheap. As the operator in
a well-equipped laboratory is able to use a camera costing L100 ($500),
it is only natural to suppose that he will also be able to command
the services of the most expensive type of microscope. On the other
hand, the independent worker, forced by circumstances to be content
with an inexpensive camera, will have to do the best he can with an
inexpensive microscope also. Yet the investigator of each class can
accomplish excellent work in his own sphere. I have seen some very
fine films of microscopic subjects which were taken with an instrument
costing less than a sovereign. From the general point of view they
compared very favourably with those obtained with an instrument twenty
times as costly. So long as the amateur does not attempt to embark upon
work which is beyond the capacity of his microscope, and is content to
work with subjects of relatively large size, there is no reason why he
should not be able to take most interesting pictures.

In the preparation of micro-cinematographic subjects it is essential
that the instruments should be mounted upon a solid base, a heavy bench
or table, so that vibrations may be as slight as possible. The camera
may be turned by hand or driven by an electric motor through belts and
pulleys.

The method of mounting the microscope in its relation to the camera
may be varied according to circumstances. In the simplest form the
microscope is mounted horizontally with the stage on which the subject
is placed set vertically, the subject itself being in line with the
middle of the cinematograph lens.

In working with the microscope it must be remembered that the objects
are seen by transparence. That is to say, the ray of light passes
directly through, or around, the object, causing it to stand out darkly
upon a luminous background. From this arises one of the limitations
of the microscope. If the subjects themselves are wholly or nearly
transparent, they become wholly or nearly indistinguishable in the
illuminated field in which they are placed. In still-life microscopical
study this disadvantage is overcome by colouring the glass slide on
which the subjects are deposited, but in cinematography this operation
is ruinous to the work for the simple reason that the aniline dye used
to colour the slide kills the microbe whose life and movements are to
be observed.

It must not be forgotten that very small organisms, as a rule, move at
a speed which is quite disproportionate to their size. Some will dart
hither and thither across the field of the microscope with the speed of
lightning, while others will move with great deliberation. In the first
case a photographing speed of sixteen pictures per second will scarcely
suffice to give a faithful record of movement. The result will be a
series of disconnected jumps. On the other hand, if the object moves
slowly, a photographing speed of sixteen pictures per second may be
too rapid. In this event the phase of movement between two successive
pictures will be so slight that the projection on the screen will
appear tame unless the express object is to indicate the slowness with
which the organism moves. And indeed this object can be achieved with
almost equally good results by taking the pictures at a slower speed,
say eight, four, or even two images per second, and thus saving a good
deal of film.

In most cases the micro-cinematographer works in a state of ignorance.
He does not know whether he is obtaining a good or a bad film. His
subject may be moving, or it may be quiescent, or it may hover round
the extreme edge of the luminous field, in which case the pictures will
be useless. When Mr. James Williamson and Dr. Spitta were engaged on
micro-cinematograph studies some years ago, they introduced a means of
following the subject through a second tube, and in this way were able
to make certain that the camera was working only during those periods
when the subject was in full activity, near the centre of the picture.
In this way a considerable saving in film was effected.

[Illustration:

 _By courtesy of the Marey Institute._

MICRO-CINEMATOGRAPH USED AT THE MAREY INSTITUTE FOR INVESTIGATING
MINUTE AQUATIC LIFE.

A. One turn one picture control mechanism. B. Camera. C. Microscope. P.
Small tank in which organism is placed, through which a stream of water
from tank F runs continually. E. Incandescent gas jet for illuminating
object.]

[Illustration: MICRO-CINEMATOGRAPHY: THE PROBOSCIS OF THE
BLOW-FLY.]

Another difficulty is the selection and control of the light. Attempts
have been made to concentrate solar light by means of a parabolic
reflector or lens, and then to throw it through the microscope slide.
The great drawback to this system is that intense heat is thrown upon
the slide containing the organisms, and for these small creatures
heat spells death. The same difficulties arise with acetylene and
electric light. What is necessary is either to extinguish the light at
intervals, in synchrony with the closing of the lens, or to intercept
it so as to keep it off the subject until the exposure is to be made.
This is done in a variety of ways by different workers.

Some years ago, when Messrs. Bull and Pizon of the Marey Institute were
engaged in the micro-cinema study of a colony of marine organisms,
they adopted the apparatus and method of arrangement shown in the
illustration facing p. 164. The microscope C was attached to the
cinematograph B which was driven by the clock A. In this case it was
only necessary to make exposures at relatively long intervals, and
to continue them through several days and nights, so as to obtain a
complete cycle of the phases of the development of the organisms.
Consequently the clock was introduced in order to make the exposures at
the right intervals.

The organisms were placed in a small flat glass tank or vessel D, and
were illuminated by the light from an incandescent gas burner. As
it was unnecessary to keep the burner alight during the periods when
the shutter was closed, Messrs. Bull and Pizon introduced a means of
turning the light up and down. This was effected by a small electric
magnet, working in synchrony with the clock and controlling the light
so that the subject was illuminated only during exposure.

As the studies were prolonged it was essential that the water in which
the organisms were placed should be kept fresh and sweet. A glass jar F
was introduced to serve as a reservoir, and from this a tube extended
to the vessel D. A constant flow of water was thus provided. Its
circulation was ensured by another glass tube extending from the vessel
P to the waste. The flow of water was controlled to a nicety by means
of a tap without the production of bubbles or any other disturbance
in the vessel D. In this manner the colony was preserved to the best
advantage and in full activity. Some such system of circulation is
necessary in all cases where the investigations are to last a long time.

In recent years the Marey Institute has much improved its
micro-cinematographic apparatus. The microscope is now carried in a
vertical position in front of the support which holds the camera. The
camera is fitted with an external bellows which carries a prism at
its outer extremity. The prism is brought over the eye-piece of the
microscope. The rays of light striking the turning mirror on the base
of the microscope are projected upwards through the object side or
vessel and then through the eye-piece to the prism. Here the rays are
bent at right angles, and are thus directed upon the travelling film in
the camera. The camera is driven electrically, the motor being mounted
within the box forming the base. Mechanism is introduced whereby the
number of photographs per second may be varied within wide limits.

The most interesting feature of this apparatus is the means adopted
to enable the worker to follow the movements of the object so that
the camera can be stopped when they are of no moment or are not
sufficiently near the centre of the picture. A small proportion of
the light rays which have passed through the microscope are deflected
from the prism mounted upon the eye-piece and thrown into a small view
finder beside the camera. Looking into this view finder one can see
exactly what is happening upon the stage of the microscope. This novel
attachment enables the waste of film to be reduced to almost nothing.

The character of the illuminant also can be varied. Sunlight may be
caught by the mirror of the microscope and projected through the
instrument as well as the beam from an electric light, incandescent
gas burner, or what not. With this effective and compact apparatus
many marvellous microscopic experiments have been carried out at the
Institute, such as the filming of the heart-beats of minute insects,
and so forth. One very fascinating investigation was that carried out
by Dr. J. Ries, of Switzerland, whereby he secured a cinematographic
record of the different phases of the union of the sperm and the egg,
as well as the separation of the membrane and segmentation of the
sea urchin. The difficulties of such a delicate study were extreme,
but the films obtained were of the utmost interest. They enabled the
investigator to reconstruct upon the screen the complete phenomenon of
fecundation. For this study the subject had to be photographed while
immersed in a small vessel containing artificially prepared sea-water,
which was renewed as required. The clock control enabled the camera
mechanism to be so turned as to secure a regular series of exposures at
the rate of seven per minute.

When Dr. Jean Comandon set himself to cinematograph the most minute
microbes, which are so small that two million may be found in a
cube measuring only one-twenty-fifth of an inch, he appreciated the
limitations of the ordinary microscope, and the impossibility of
obtaining images clearly and distinctly therewith. So he resorted to
the ultra-microscope. With this instrument the light is not thrown
directly through the slide containing the object, but is directed upon
it by reflection from a light which stands at one side. Beneath the
object to be examined is placed a glass prism, or condenser, set at
right angles to the optical axis of the microscope, the result being
that the light enters the slide through the edge. The objects under
examination, instead of appearing as dark objects against a luminous
ground as in the direct transmission of the light, appear luminous in
themselves and stand out as bright spots against a dark background. By
the aid of this instrument, particles which are beyond the scope of
vision with the highest powered microscopes may be seen with ease.

Thus this French investigator was able to photograph even the most
minute organisms. The well-known firm of Pathe Freres placed their
laboratory and resources at his disposal, so that the work might be
done under the most favourable conditions. Even then two years passed
before a successful detailed film was obtained, and an apparatus made
perfect for this class of work.

The complete apparatus is set upon a massive bench, so as to secure
absolute rigidity, because vibrations are fatal to good results.
Slight modifications are sometimes needed, but in most cases the same
appliances are used, and in the same way. The light is furnished from
a 30-ampere electric arc lamp. In front of this is arranged a series
of lenses for concentrating and varying the rays, while all excess of
luminosity is cut off from the microscope by means of a diaphragm. The
microscope itself is set horizontally, with its longitudinal optical
axis in line with that of the camera, and its eye-piece brought against
the camera lens. The camera is one of the Pathe models with detachable
dark-boxes.

The ray of light thrown from the electric lamp is concentrated and
then falls upon the microscope condenser, which deflects it so that
the objects under study become illuminated, no light entering the tube
of the microscope. The camera may be turned by hand, or by a small
electric motor, the latter giving an improved rotary motion with the
least possible vibration.

[Illustration: THE MICRO-CINEMATOGRAPH USED AT THE MAREY
INSTITUTE.

A. Special condenser. B. Electric arc light. C. Camera. D. Shutter
between light and object. M. Microscope. O. Object under examination.]

[Illustration:

 _By permission of Pathe Freres._

ONE OF DR. COMANDON'S GALVANIC EXPERIMENTS WITH PARAMOECIA.

Under the action of electric current the organisms perform strange
evolutions.]

One of the difficulties which harassed all the early efforts in
micro-cinematography was the control of the light so that the subjects
might not be killed by the heat generated by the concentrated rays. At
first an investigation could not be continued for more than a second
or two, because the microbes were killed by the heat. Seeing that the
pictures were taken at the rate of sixteen per second, an intermittent
lighting system in synchrony with the opening of the lens was difficult
to obtain, as there was the risk that the maximum illumination might
not be thrown upon the subject at the precise fraction of a second
during which the lens was open. Many ingenious expedients were tested
to remove this disability, but without success, until at last Dr.
Comandon conceived the idea of introducing a rotary shutter, similar
to that fitted to the camera itself. This was tried, the shutter being
placed between the condensers and the stage on which the objects were
set up. This shutter was revolved by the same mechanism as drove the
camera shutter, and was so timed that the opaque sector interrupted
the ray of light at the same moment as the camera shutter eclipsed the
lens. In this way the microbes were protected from the heat of the
light while the lens was closed, and it was possible to keep them alive
and in full activity in the slide for a considerable time. Repeated
experiments suggested improvements in this shutter, and now the
scientists employ one in which there are two or three opaque sectors
of equal area spaced equidistantly, so that only a flash of light is
thrown upon the microbes at the instant of exposure. Still further to
lessen the evils of the heat a water condenser has been introduced
between two of the glass condensers placed near the lamp. This is a
small circular vessel like a big lens. It is filled with cold water and
provided with the means to remove the ill effects of bubbling when the
temperature rises to boiling point. The system is very much the same as
that adopted by the Lumiere Brothers when they first used the electric
arc for the purpose of projection and with the same object--to protect
the inflammable celluloid film from the heat radiated by the light.

With this ingenious and simplified apparatus Dr. Comandon has prepared
some very remarkable films which have served to introduce the picture
palace patrons as well as the scientists to phases of life about which
little was formerly known. When thrown upon the screen the subject in
some cases is magnified as many as fifty thousand times, so that the
infinitesimal organisms stand up as large as dinner plates and their
movements and structure and habits can easily be followed by the eye.

When the earliest films prepared by Dr. Comandon were shown by Dr.
Dastre, of the Sorbonne, to the French Academy of Sciences, it was
immediately realised that this was a new and reliable means of studying
bacteria, and that many questions which heretofore had proved utterly
unanswerable could now be solved with ease and precision. A little
later the films were introduced to the public, and although it was
feared that they would prove of only fleeting interest to the man in
the street they have really interested him almost as deeply as the
scientists. Good films of bacteria never fail to please a picture
palace audience.

At present the preparation of these films is confined to a very small
band of investigators. So far as bacteriology is concerned it is expert
work, but there are many applications within the reach of the average
microscopist. Cinematography has been of use in spreading the knowledge
of the facts of health and hygiene, and now that there are propagandist
movements on these subjects the aid of the living pictures will be more
than ever appreciated.




CHAPTER XIV

MICRO-MOTION STUDY: HOW INCREASED WORKSHOP EFFICIENCY IS OBTAINABLE
WITH MOVING PICTURES


In these days of competition it is obvious that the establishment in
which the machinery is most efficient, the workmen most skilful, and
the labour most economically expended has the best chance of success
in its particular line of business. These are the days of scientific
organisation and management, the value of which, developed upon
rational lines, cannot be denied.

But it has remained for the cinematograph to indicate the true lines
along which such developments should be continued. For instance, there
may be two workmen of equal skill and industry, each of whom is given
an identical job. One completes his task in less time than the other,
although the two men are admittedly of equal ability. They may be
checked from stage to stage by the stop-watch, but this will reveal
nothing conclusive, as the advantage from stage to stage will fluctuate
between the two. It is only in the aggregate that the superiority of
the one over the other is seen. The superiority may be so slight as
to be almost negligible, but the fact that it exists is sufficient to
prove that there is something wrong somewhere.

Where is it? How can it be detected? Hitherto scientific management and
stop-watch methods have been found wanting. The riddle can be solved
in one way only, as investigations have shown, and that is by moving
pictures.

This new phase of scientific management has been evolved and perfected
by Mr. Frank B. Gilbreth, of New York, an eminent authority upon
the subject of workshop organisation. He has given it the title of
"Micro-Motion Study." As the name implies it concerns the investigation
of small movements by the ordinary standard cinematograph and the time
measurement of each action.

While this particular line of study may not be entirely new, since
Marey and his contemporaries in the study of movement indicated such a
possible application, yet Mr. Gilbreth is the first to reduce it to a
science. Therefore he is justly entitled to the credit of perfecting
this most important development of scientific management.

Everything depends upon the timing mechanism. This must be of the
simplest type and of unimpeachable accuracy. In a previous chapter
I have described the "chronoscope" which was used by Marey. Mr.
Gilbreth, for the purposes of his work, has evolved a clock working
upon a similar principle. This clock, fitted with one hand, is designed
to make one complete revolution in six seconds. The indications on
its dial are as follows: The larger divisions represent tenths of
a revolution. Each of these is divided into two, thereby showing
twentieths of a revolution, and these latter are further sub-divided
into fifths, so that the dial is divided into one hundred parts. Each
of these divisions represents the thousandth part of a minute, while
the clock can be read easily to half-thousandths of a minute.

This clock, together with one of the ordinary type, is used in each
investigation. Both are prominently displayed in the image so that the
time interval from picture to picture may be determined exactly. The
ordinary clock is necessary, as it shows the total time occupied in an
operation. The special clock, on the other hand, serves for timing the
different stages or motions involved in completing the task.

The principle may be utilised in a variety of ways, as has been proved
at the works of the New England Butt Company of Providence, Rhode
Island. The manager of this concern, Mr. J. G. Aldrich, was one of the
first to recognise the value and possibilities of micro-motion study.

[Illustration: MICRO-CINEMATOGRAPHY: BLOW-FLY EATING HONEY.]

[Illustration: The ingenious Gilbreth clock, graduated to
one-thousandths of a minute.

The rack, showing disposition of component parts for the assembling
test.

MICRO-MOTION STUDY: THE LATEST DEVELOPMENT IN SCIENTIFIC
MANAGEMENT.]

It is an establishment devoted to the manufacture of machinery for
making braiding, such as trimmings for ladies' dresses, and so forth.
The machines are built for the most part from small light castings,
which are machined only slightly, but which must fit together without
the necessity of filing or finicking hand-work. In order to improve
the efficiency of the factory and incidentally to augment its output
and profit, experts were called in from time to time to say where
modifications of process might reduce the manufacturing costs.
Different operations in the assembling of the pieces were timed. The
result was the discovery of more expeditious methods of putting the
pieces together. Such time-study investigations also supplied a basis
for computing the various scales and systems of payment for work done.

Notwithstanding the high pitch of efficiency to which the factory was
brought by these methods, Mr. Aldrich felt convinced that still further
speeding-up might be accomplished without over-driving the men. So he
called in Mr. Gilbreth and his cinematographic method. In order to
obtain the highest results, the most expert workman was taken as the
subject of the experiment.

In one corner of the assembling room the wall and floor were marked off
into four-inch squares. In this space was placed the bench, together
with the sets of component parts. Here there was a slight divergence
from the existing practice in the factory. Instead of taking the
pieces from various boxes, packets of parts were placed in convenient
positions upon a rack. These were placed in the proper sequence, so
that the workman was saved the task of thinking when selecting the
successive pieces. He was able to take them up quickly and correctly in
a mechanical kind of way.

The timing clocks were placed in a prominent position facing the
camera, and when all was ready, the workman was given the word to
start. The whole operation of fitting the pieces of a machine together
were filmed in this manner so as to give a complete cinematographic
record of the assembling of a machine.

Now in micro-motion study the films are not intended for projection.
Instead of being screened, the pictures are studied with the aid of a
magnifying glass, the motion in each picture being closely examined
to detect whether it is essential to the task, whether it might be
eliminated, or shortened. As the wall and floor are marked off into
four-inch squares, the investigator is enabled to ascertain the precise
length of each movement in picking up and fitting the parts. At the
same time, such marking-off enables the expert to see whether the bench
and rack of packets containing the component parts of the machine are
disposed most advantageously in relation to the mechanic, and also
whether the latter stands in the most convenient position before his
work, to fulfil his task in the shortest possible time and with the
minimum of physical effort.

As might be supposed, the individual study of each picture in a film
together with the following and timing of each elementary motion is a
tedious task for the expert. This may be realised when it is pointed
out that the time interval for each picture is only 1/32 part of a
second. But the labour is not wasted. The searching analysis is sure
to reveal where a movement may be accelerated here, or eased there,
why it would be preferable to set the rack in this position, or why
it would be better if the mechanic faced his work in such and such a
way. This is the sole object of micro-motion study. Nothing rivals the
cinematograph for picking a movement relentlessly to pieces.

The most expert workman is taken for the purpose of the investigation
because his skill must be dependent upon his ability to reduce
movements to the minimum. Moreover, he serves as an excellent model
for speeding-up if such is required. By the time his workmanship
has been analysed and perfected by the elimination of all waste or
unnecessary motions, and by his mastery of the best methods, the
photographing in animation of his experience serves as a pattern for
the benefit of all in the factory.

Some remarkable results have been accomplished by this new phase in
scientific management. In the above-mentioned braiding factory the
analysis of the movements incidental to a particular operation enabled
the time occupied upon one task to be reduced from 37-1/2 to 8-1/2
minutes. In other words, the workman was able to perform more than
four times his previous volume of work in an eight-hour day after his
motions had been analysed by the cinematograph. Nor is he driven harder
to achieve this end: he is able to do it because all waste motions have
been eliminated.

The great value of micro-motion study is that it facilitates the
transmission of skill from man to record. It provides a reliable way
of transferring experience from a man who has gained it to one who has
never had it. It acts as a check upon the work. The establishment is
provided with an unassailable record of the time occupied throughout
every department, and consequently holds a complete check upon the
skill and capacity of every man. If there is a decrease in the output,
showing slackness to exist somewhere, it can be traced before material
damage is inflicted. Every workman is kept up to concert pitch, and the
maximum work per man is obtained without resort to driving or rushing.

There is no limit to the applications of micro-motion study. Obviously,
although the best efforts of every man are required, it is essential
that the records should be taken under normal conditions, so as to
provide a fair basis. To introduce special arrangements for the test is
to destroy the value of the investigations, because the other men will
retort that they cannot equal the performance unless they have the same
facilities.

The workmen are never permitted to see the moving-picture record of
their work. Neither are they shown contrasting views of how and how not
to do a thing. The pictures are merely for the use of the investigator.
When it is necessary to communicate the results of an experiment to the
workman, he is given no opportunity for argument. He is merely told
how to do this or that, according to the experience gathered from an
intimate study of the photographic record.

This application of the cinematograph has been developed also for
the benefit of apprentices. A youth who is trained on the correct
lines from the very commencement of his duties has the best chance of
becoming an expert workman, and for him the use of micro-motion study
is invaluable. He can be taken through every separate motion step by
step, the film used for this purpose being that of the most perfectly
skilled man. Experience has shown, moreover, that a youth can learn his
craft more quickly and intelligently by following it upon the screen
than by being brought face to face with the actual work at the bench.
He appears to concentrate his attention better upon the moving-picture
lesson than upon the practical demonstration, although in both cases
the appeal is made to the eye.

There is yet another valuable aspect of this work. Enterprising and
ingenious men are constantly devising improved processes in factory
equipment. At times their revolutionary ideas are put into practice
before they are thoroughly understood, and the result is far from
satisfactory. The improvement proves to be more imaginary than real.
But if recourse is first had to the cinematograph, the process can be
submitted to a searching practical trial before it is installed. A film
can be taken and each separate image can be examined minutely with the
aid of the magnifying glass, until a pretty complete idea is gained as
to the true value of the invention. The pictorial time record can be
compared with the best results secured under the existing practice, and
the manufacturer can ascertain what economies the new plan will effect
before a penny is expended, or the working of his factory disorganised
by the alteration.

[Illustration: Mr. Frank B. Gilbreth cinematographing a man's work
against time, showing the Gilbreth clock.

Bench and parts arranged after test so as to secure assembling of
machine with fewest and shortest motions.

THE GILBRETH METHOD FOR IMPROVING FACTORY EFFICIENCY.]

[Illustration:

  1      2

MICRO-MOTION STUDY: FILMS SHOWING HOW A MAN'S WORK IS ANALYSED BY
MOVING PICTURES.

These pictures are not thrown on the screen, but are examined by a
magnifying glass.

(1) Film of workman assembling machine, showing Gilbreth clock and
ordinary timepiece alongside.

(2) Film of rack and bench, floor marked off into 4-inch squares, and
Gilbreth clock.]

Micro-motion study by the aid of the cinematograph is still in its
infancy. But it appears to have a wide field of utility. The pictures
can be taken at any desired speed, according to the character of the
work photographed, but as a rule sixteen pictures per second will
suffice. It must be remembered that in this case the record is not
obtained for the purpose of studying movement from the scientific or
physiological point of view, as with Marey's investigations, but purely
for the purpose of discovering whether certain motions are necessary to
certain tasks. Obviously the expert engaged in this work must possess
an intimate knowledge of movement so as to be able to follow the
motions closely and accurately through their natural cycles, and must
also be familiar with the work of the factory so as to tell whether
a man is working to the best advantage. This faculty alone demands a
long apprenticeship, for experience is the only guide. Mr. Frank B.
Gilbreth, who has brought micro-motion study prominently before the
public, has devoted years to the subject. He has become an unique
authority upon it. Now that its advantages are appreciated, one may
expect it to fill an even wider space in industrial life, and to be
applied in many directions that are as yet undreamed of.




CHAPTER XV

THE MOTION PICTURES AS AN AID TO SCIENTIFIC INVESTIGATION


Rapid strides are being made in the utilisation of animated photography
as an aid to scientific investigation. It is a development useful in
all fields of research where phenomena can be recorded in pictorial
form. Dr. E. J. Marey, the eminent French scientist, was the pioneer
in this work. One has only to peruse his classic work "Movement"[4]
to realise the comprehensive nature of his studies. So thoroughly did
he cover the ground of chronophotography, as it was then called, that
it is difficult to conceive where any new application of the motion
picture can now be made.

[4] "Movement," by E. J. Marey. Heinemann, 7_s._ 6_d._

The Aurora Borealis always has been a subject fascinating to
scientists. Numerous papers and brochures have been written about it,
and many elaborate drawings have been prepared to convey some idea
of its characteristics and its kaleidoscopic changes. The drawings,
however, fail to convince, and even the few still-life photographs
which have been taken are uneventful.

Realising this deficiency a Danish professor is striving to record the
Aurora Borealis in motion upon the celluloid film. A special camera
has been designed for his work, and with this it is intended to snap
the phenomena from a convenient northern point such as Spitzbergen or
Greenland, not only for the benefit of the scientific world but also
for the general public which entertains only a hazy conception of the
"Northern Lights." It need hardly be said that if this investigator
should succeed in his difficult quest he will reveal upon the screen
one of the most extraordinary wonders of the world. While the
marvellous and weird colouring effects will be missing, the curtains of
light that drape the sky, and the strange luminous shafts and glares
which light the heavens, should provide a film of intense interest and
fascination.

The moving-picture camera is also being applied to the recording of
solar eclipses with a view to obtaining a more impressionistic and
intimate idea of the activity and extent of the flames which shoot from
the surface of the sun. Wonderful still-life pictures of these effects
have been taken, and it is only fair to assume that they should be
capable of being caught by the motion-picture camera. Efforts are also
being made to secure photographs of the heavens, but the difficulties
are very great. The long exposure required in this case is a heavy
drawback, but seeing that the slowest movements of Nature can be
recorded by the cinematograph, and may be speeded up in projection to
convey the effect of animation, there is no reason why similar moving
pictures of other worlds should not be obtained by combining the
moving-picture camera with the telescope. The moon followed through its
phases would yield an interesting study, and, incidentally, a film of
this character would possess considerable educational value.

At the present moment great activity is being manifested in the
application of the cinematograph to mechanics. Two Sheffield
investigators have designed a steel-testing machine to which is
attached a microscope and a cinematograph camera. The piece of steel
to be tested is placed in the machine and the cinematograph is set
in motion. By throwing the resulting pictures upon the screen it
is possible to follow exactly what takes place in the molecular
construction of the steel while it is under test.

The idea has been applied to many other phases of mechanics with equal
success, and there have been many discoveries of a technical nature
which have had their effect upon manufacturing processes.

Another series of technical experiments was carried out by Dr. Otto
Fuechs, professor of engineering at the German Technical High School of
Bruenn. The purpose was to elucidate some hitherto obscure points in
connection with the working of steam hammers. Investigations in this
field have hitherto proceeded on the graphic principle, the results
being recorded by a stylo continually travelling over calibrated paper.
It is admitted that this system leaves much to be desired because the
stylo is not sufficiently sensitive, and fails to record many of the
smaller and more important movements. Accordingly, Dr. Fuechs conceived
the idea of using the moving-picture camera in the anticipation that
much missing data might thus be discovered.

A special apparatus was designed. In reality it is an ingenious
combination of the moving-picture camera and the graphic method. There
is a paper tape that passes continuously over two rollers and has two
stylos constantly bearing on it. These stylos are connected with two
indicators attached to the sides of the cylinder of the steam hammer,
and they supply a continuous record of the steam pressure. The paper
tape is moved by an electrically-driven gear, while time intervals are
indicated by means of clockwork mechanism. So much for the graphic
portion.

[Illustration:

 _By courteous permission of Dr. Otto Fuechs._

MOVING-PICTURES OF A STEAM HAMMER RAM.

An illuminated index attached to the ram moves over a graduated scale,
while an illuminated clock indicates the lapse of time.]

[Illustration: DR. OTTO FUeCHS' APPARATUS FOR TAKING MOVING-PICTURES
OF THE OPERATIONS OF A STEAM HAMMER.]

What the cinematographic portion supplies is a continuous animated
record of the movement of the ram of the hammer. Attached to the ram is
an index which moves up and down over a scale divided into centimetres.
Both the index and the scale are illuminated so that the result given
by the camera shows a series of photographic images of the oscillating
motion. Above the illuminated finger and scale is a clock similar to
Marey's chronoscope and Gilbreth's timepiece, driven by clockwork, and
in synchrony with the remainder of the mechanism. This scale likewise
has its points of division illuminated. Its use is to supply the time
factor without which such experiments are useless.

The ram, the index-finger, the scale and the clock are all recorded
upon the film, so that it is possible to tell the varying speeds at
which the ram moves throughout its travel. The photographing speed may
be varied as desired, and as a different position is caught in each
picture, the distance the ram travels between two successive exposures,
together with the time occupied in completing the cycle of movement,
may be accurately gauged. The combination of the paper tape recorder
with the photographic part of the apparatus affords a complete record
of the ram's performance.

The results are naturally of a severely technical character and of
interest only to persons concerned with mechanics. But to these they
are very important indeed. The experiments which have been completed by
Dr. Fuechs have thrown much light upon a difficult engineering problem.
They have served to answer questions affecting the design of the hammer
and its most economical efficient operation which would otherwise
have been insoluble. From the public point of view the films possess
no interest whatever, inasmuch as the subject is illuminated and
photographed in such a way that only the features of technical interest
are brought out strongly upon the film.

Another interesting and profitable province of the cinematograph is
that concerning ballistics. This has been worked out by Monsieur Lucien
Bull at the Marey Institute with his camera capable of taking two
thousand pictures per second under the illumination of the electric
spark. While this investigator did not apply his invention directly
to ballistics he indicated the manner in which such work could be
carried out. The success of his experiments, however, prompted another
investigator to enter the field. This was Dr. Cranz, of the Berlin
Military Academy. The apparatus this professor evolved has been
devoted exclusively to the study of the flight of projectiles and to
photographing the action of the mechanism of the magazine type of
firearm.

[Illustration:

 _By courtesy of the Marey Institute._

THE WONDERFUL APPARATUS DEVISED BY MR. LUCIEN BULL FOR TAKING 2,000
PICTURES PER SECOND.

Showing stereoscopic camera, interrupter, condenser, coil, and
resistance. Illumination is obtained by the electric spark.]

[Illustration:

  (1)      (2)

FILMS PREPARED BY PROFESSOR CRANZ WITH HIS REMARKABLE CAMERA.

(1) Moving-pictures of the ejection of a cartridge from an automatic
pistol.

(2) Motion photographs of the splintering of a bone by a bullet.]

The Cranz apparatus is somewhat more complicated than that designed
by Monsieur Bull, though the fundamental principle of operation is
the same. The film, resembling an endless belt, is passed round two
steel cylinders, one of which is driven by an electric motor. Images
of standard size are produced under the illumination of the electric
spark, which concentrates the maximum amount of light upon the moving
object. The photograph is in silhouette, and the disposition of the
apparatus is such that five hundred consecutive pictures can be made
in one-tenth of a second, the period of exposure varying between
one-millionth and one-ten-millionth of a second. The outstanding
feature of the installation is the special and novel type of
interrupter. It consists of a pendulum by which the sparking is started
before the projectile is fired and made to continue until the film has
been exhausted.

Some of the results obtained by this apparatus are very remarkable.
When the films are projected upon the screen at the average speed of
sixteen pictures per second the flight of the bullet can be followed
with ease. One film shows the effect of a bullet striking a suspended
india-rubber ball filled with water, and brings out the remarkable
formations the ball assumes during the infinitesimal part of a second
when the bullet is passing through it. Another interesting film shows
the effect of a high velocity bullet striking a bone, and the manner
in which the bone is splintered and smashed by the force of the impact
conveys a realistic impression of the destructive force of the modern
rifle projectile. The deadliness of the automatic pistol is well known.
Since seven shots may be discharged in four seconds, the movements of
the mechanism are too rapid to be followed by the naked eye. Yet by
means of the Cranz apparatus every motion is caught, and the whole is
slowed down in projection to such a degree that the complete cycle
of the firing of the shot and the expulsion of the cartridge, which
normally occupies only a fraction of a second to complete, occupies
about thirty seconds upon the screen. When these pictures were
exhibited for the first time a number of black specks were observed
to accompany the expulsion of the spent cartridge. These proved to
be grains of powder which had not been ignited. Their existence had
never before been suspected, and the result was curious. After minute
examination of the pictures a change was effected in manufacture of
the cartridge so that the waste of powder through non-ignition should
be reduced to the minimum. The success achieved in this direction was
shown by the absence of non-ignited grains in subsequent pictures.

Another wonderful series of moving pictures was prepared by an
American ophthalmic surgeon. He embarked upon elaborate researches
to gain further information about the eye and its peculiarities both
in sickness and in health. The illumination of the eye was carried
out very cleverly, so as to obtain the greatest possible brilliancy
without causing fatigue to the subject. Accordingly his pictures were
absolutely normal. In these experiments glass plates were used, for
the reason that they give results much finer and more detailed than
celluloid. In celluloid the grain of the base of the film is apt to
be disturbing to very fine studies. In this way a great deal of new
information was gained. One of the most remarkable discoveries was
that the sensitiveness of the organ of sight is far greater than was
previously supposed, and that the eye never is absolutely still, even
when commonly regarded as being fixed and steady.

During the past two or three years the uses of the cinematograph in
medicine have been much extended. A former chapter has described its
application to the study of microbic life, but the latest innovation is
to employ it in the operating room. The pages of the medical papers
are filled with reports of curious and unusual surgical operations,
but mere reports are necessarily somewhat imperfect. In view of these
circumstances it occurred to one eminent surgeon that a cinematographic
record would form a first-class supplement to the technical
description. The initial experiment proved a complete success, and
accordingly the practice has been extended. In this direction France,
Germany, and the United States are taking a very active part. Films
of this character can be made to serve two useful purposes. They are
valuable for the transmission of practical information between medical
men and are useful in the lecture room among the students. Suppose a
hospital in New York has a strange and unusual case for operation. Only
the students in that establishment have the opportunity of witnessing
it. But by the aid of the moving-picture camera and a lecture it can be
reproduced in photographic animation upon the screen for the benefit of
medical graduates in the various hospitals throughout the world.

In research work, such as the study of new and unusual diseases,
especially those of a tropical nature, it is possible to obtain a
continuous record of a subject from the moment of infection through the
various stages of the malady. For instance, in the study of sleeping
sickness in Uganda, Colonel Bruce had formerly to content himself with
a graphic record or chart of the fluctuations of a patient's condition,
with explanatory notes introduced here and there when a sudden change
in the temperature or general behaviour of the patient developed.
With the cinematograph it is possible to obtain a pictorial record
which conveys a more forceful and exact impression of the symptoms.
An interesting indication of what could be done in this direction was
the film prepared by Dr. Comandon. He used a monkey for his subject,
infecting it with the microbe of sleeping sickness discovered by
Colonel Bruce. The effects which the bacteria produced upon the monkey
were admirably illustrated, together with the changes that various
remedies wrought in its condition.

So far as concerns the application of the cinematograph to scientific
research the greatest strides have been made in physiology. This
was due to Marey's enthusiasm in this branch of science, and the
establishment of the Physiological Institute in Paris where such
investigations were carried out upon a most exhaustive scale. The
results of Marey's investigations are given in several volumes
and in hundreds of papers which he sent to the various French
scientific societies. There is no reason why the contributions of
the cinematograph to physiological knowledge should not be equalled
in other branches of science. Up to the present the investigation of
scientific phenomena with the aid of motion-pictures has not been
carried far, but there are many signs that its sphere will be extended
in the future.




CHAPTER XVI

THE MILITARY VALUE OF THE CINEMATOGRAPH


Among the many uses of the cinematograph, frivolous and useful, amusing
and instructive, perhaps none has proved so difficult or illusive as
the attempt to apply it to soldiering for the purpose of improving
marksmanship. The motion-picture had scarcely impressed itself upon the
public when the war departments of the various powers were flooded with
suggestions and patents for its employment in this sphere. Needless
to say the majority of these ideas were found to be impracticable,
and probably this is the reason why the animated target has not been
seriously taken up by military authorities.

Notwithstanding the many disabilities under which the cinematograph
labours, it is generally admitted that it has real practical value in
this field up to a certain point. It is able to induce the recruit
to aim quickly and surely, and this is to-day recognised as being
the governing consideration whether the range be point-blank or
long-distance.

One of the first practical developments in this direction was that
perfected by Messrs. Paterson and Musgrave. Their wide and diversified
experience of all that pertains to shooting and targets enabled them to
avoid the defects of the system, which to many experimenters were not
apparent owing to a lack of knowledge.

The apparatus and method of operation were very simple. The target
consisted of an endless roll of white paper which served as the
screen, and upon which the pictures were projected from a point near
the firing line. A self-recording system was incorporated whereby the
result of a shot was transmitted back to the firing line to inform the
marksman about the value of his hit. As the paper became perforated
under the fusillade it was rolled up. The most important feature of
this invention was the mechanism placed behind the screen, which
synchronised with the movements of the objects at which the marksman
aimed.

In cinematographic projection, however, the throw of the picture
cannot be extended beyond certain limits, that is, if a clear view
is to be presented to those seated farthest away from the screen. In
target practice this is a serious disadvantage. At a range of 200 feet
marksmanship would be almost impossible, owing to the indistinctness of
the image upon the white wall. At that distance one always receives
an impression of flicker. Why this should be so is not quite apparent,
though it is evidently governed by some law of optics. Suppose, for
instance, that a picture is being followed from a distance of 200
feet, and a straining of the eyes is experienced. This may be overcome
merely by looking at the screen through the reverse end of a pair of
field glasses. As is well known, this usually makes the object appear
to recede to a great distance, but when it is done in connection with
moving pictures it makes the images stand out more brilliantly and
distinctly, while they are far steadier, the flickering being almost
entirely eliminated. In fact, if one wishes to witness a projection to
the best advantage with the minimum of eye fatigue, this is the way to
do it.

It is obvious, under these circumstances, that the distance of the
marksman from the target is restricted somewhat severely. From 75 to
100 feet is considered to be the greatest distance from which shooting
can be practised to advantage. Since the modern automatic pistol will
carry about 80 yards, while the latest types of rifles have a range
of 1,000 yards or more, doubts may be raised as to the utility of the
cinematograph in marksmanship. In the Paterson-Musgrave invention an
ingenious attempt to overcome this disability was made by what might
be termed a "range compensation." This end was achieved by making
the figures of varying sizes, according to their distance from the
marksman, so that a target of varying size was presented. Thus in one
case the man would appear in the foreground of the picture and be of
relatively large size, corresponding to the target he would offer
at a distance of 100 yards. Then he would be shown somewhat smaller
to represent 500 yards, and so on, until at the higher distances he
offered a very small target indeed.

From the military point of view the incidents were made as exciting as
possible, and closely analogous to actual war conditions. As a case in
point, the man on the screen would be shown behind cover, and aiming
directly at the man on the firing line. His movements could easily be
followed. He would be seen to expose himself slightly to sight his
rifle and then to fire. The effect upon the marksman firing at the
target was thrilling in its apparent realism, because he unconsciously
developed the feeling that he had got to shoot first, and straight, or
he would be hit. The self-recording system enabled him to judge whether
he had got his shot well home, while the judge could decide whether the
marksman or the photographic enemy had fired first.

The judicious selection of subjects for portrayal upon the screen
undoubtedly served to develop a sense of smartness among the marksmen.
A decided improvement in quick-sighting or snap-shooting was obtained
together with a concentration upon the work in hand.

Projection was carried out upon purely automatic lines. The projector
was set working by a button control placed at the firing point, and
pressed by the marksman or his officer. The instructor or officer had
thus a complete control over the whole installation, and was in a
position to make sure that his instructions were being followed, as
well as being able to tell whether his men were quick in sighting.
Despite the many ingenious features incorporated in this idea, it does
not appear to have met with official approval.

There has recently been another invention, based upon a similar
idea. This is what is called the "Life Target," and it is ingenious,
practical, and well thought out, especially from the mechanical and
electrical points of view. The original idea was suggested by a
non-commissioned Irish officer who fought through the Boer war. His
suggestion in its crude form, however, was scarcely feasible, but there
were three other patents available, each of which had been designed
for a different purpose, and it was realised that a combination of the
four would enable a practicable cinematographic target to be produced.
Even then, innumerable experiments were required before perfection was
gained.

In this invention the salient feature is that when a shot is fired
at the screen the whole of the mechanism is stopped for a very brief
period, and the hit is indicated by a bright spot of light on the
target. Consequently the marksman is able to ascertain instantly the
effect of his shot, and has no need to remove his eye from the object
at which he has aimed. This is a distinct advantage, because the
marksman can keep his sight ready for the succeeding shot, which may be
fired instantly the mechanism resumes working. Directly the film begins
to move once more the previous shot represented by the illuminated spot
upon the target is extinguished.

The apparatus, as described, appears to be rather complicated, but
as a matter of fact its working is extremely simple. The projector
is mounted at a convenient place near the firing point, so that a
truly square picture is presented to the marksman. In front of the
firing line, and above the picture, is a very sensitive microphone or
telephone receiver. Connected with this is a delicate relay, which
really forms the heart of the mechanism.

When a shot is fired the report acts upon the microphone and upon the
relay in turn. Immediately a magnetic clutch, which is placed upon
the motor drive of the projector, is released, and a brake arrests the
movement of the projector mechanism. Thus, the passage of the film is
stopped in the gate, so that the picture remains stationary upon the
screen.

The screen itself consists of three separate sheets of specially
prepared thick paper. The front sheet is coiled upon a horizontal
roller which is mounted at the bottom. From this it is carried up and
over a second horizontal roller at the top of the screen space, and
then down again behind the front sheet, to be coiled upon a third
horizontal roller, mounted above the first one. As the lower front
roller can be moved or "fed" the paper is free to travel upwards over
the top roller, and down again to be wound upon the third roller.
Behind these two thicknesses of vertically travelling paper is mounted
a third sheet. This is coiled upon a vertical roller at one side,
passed across the back of the two front sheets, and coiled round a
second vertical roller on the opposite side. It is kept very taut, and
serves to hold the two sheets in front in close proximity. It is moved
by hand at intervals.

Behind the screen are a number of arc electric lights, or other
illuminants, out of the firing line. In this way the space behind the
screen is brilliantly lighted. As the paper remains stationary while
the projector is running, it follows that a shot must penetrate the
three thicknesses of paper, and the puncture is shown by the light from
behind coming through the shot-hole. Thus the marksman can see where
his shot has struck.

When the projecting mechanism has been stopped, and the result has
been read, the shot-hole has to be obliterated before the film is able
to resume its forward movement. This is accomplished automatically
as follows: The relay, while declutching the drive and applying the
brake, also sets in motion a plunger in a dash-pot. The time of the
vertical travel of this plunger is varied, but the mechanism remains
stationary, and the shot-hole visible, during its movement. When it has
reached the limit of its travel it establishes contacts which serve
to set the screen mechanism in motion. On the lower horizontal roller
carrying the supply of paper is a ratchet and pawl movement, actuated
by a solenoid. When the plunger connected with the relay closes the
screen mechanism circuit, the ratchet is moved, and the outer sheet of
paper moves upward one-eighth of an inch, while its return forming the
second sheet moves simultaneously and correspondingly downwards. The
displacement of these two vertically moving sheets disturbs the line of
holes caused by the shot, and through which the back light was shining,
so that the spot of light is extinguished, and an opaque screen is
presented. The inclusion of the third or back paper not only serves as
a stiffener, but also acts as a means of lessening the possibility of
a repeat, especially as it is moved gradually and at long intervals
in a transverse direction. The movement of the travelling surfaces of
paper is extremely small, approximately the diameter of a shot-hole,
so that the consumption of paper is very low. When the first roller
has been exhausted it is only necessary to replace it by the roller on
which the paper has been rewound, and the paper can be used over again.
The possibility of three old shot-holes coming once more into line
without a shot being fired is so extremely remote as not to be worth
consideration.

[Illustration: SOLDIERS FIRING AT THE "LIFE TARGET."

The picture on the screen is thrown from the projector at right, and
the picture is held stationary by the action of the report of the rifle
caught by the microphone (marked X) upon the lantern mechanism.]

[Illustration: FRONT VIEW OF THE "LIFE TARGET," SHOWING SCREEN
OPENING.]

From this it will be seen that the final stage in the cycle of
movements arising from the action of the rifle report upon the
microphone, and the relay, is the movement of the paper forming the
screen or target. The time during which the picture remains stationary
may be varied within certain limits, but normally it is about a couple
of seconds. When the paper has moved, obliterating the shot-hole, the
brake on the projector is released, the magnetic clutch re-engages, and
the film resumes its travel. The ingenious means adopted for stopping
and restarting the projector will be appreciated as a great feature of
the invention, and though the action may appear to be abrupt, no damage
whatever is inflicted upon the film.

One point about this apparatus deserves attention. In the ordinary
projector, if the celluloid film is stopped in the gate for a fraction
of a second, and is exposed to the light, it flares up instantly, owing
to the great heat emitted by the illuminant and the high inflammability
of the film. As it is necessary to allow the film to stand still upon
the screen in this case, after the shot has been fired, means had to
be found to keep it sufficiently cool to prevent combustion. This is
done by a radiator arranged around the condenser, which in itself is a
special kind of cooling tank.

Another noteworthy point is the way in which a still-life lantern
slide is thrown upon the screen when desired. The projector carries
two lenses, one for animation, and the other for still-life lantern
slide work. The ordinary way of bringing the latter into use is to
push the front part of the projector bodily sideways so as to bring
the second lens before the condenser and the light. The objection to
this method is that the rigidity of the projector is likely to be
disturbed, especially after a little wear, with the result that the
projection of the moving pictures is apt to become unsteady. In this
apparatus a mirror is placed in the lantern and set at an angle of 45
degrees. By this means the light can be diverted and thrown through the
lantern slide lens. Thus it is not only possible to throw a still-life
slide upon the screen at the instant when a moving-picture scene is
completed, but excellent dissolving effects can be obtained.

[Illustration: THE SCREEN MECHANISM OF THE "LIFE TARGET."

The movement of the rollers and paper forming the screen is made by
means of a solenoid operated by the lantern mechanism.]

[Illustration:

 _By permission of the Motograph Co._

CINEMATOGRAPHING HEDGE-ROW LIFE UNDER DIFFICULTIES.

Mr. Frank Newman and his camera concealed in the scrub.]

The pictures are projected at the normal speed, but this may be
accelerated if necessary. Any films suited to the subject may be used,
hydroplanes, airships, birds, wild animals, and so forth, just as
successfully as the military films prepared specially for the work. In
fact any picture where movement is portrayed is equally applicable,
so that the marksman can become used to all sorts of conditions.
Experience has shown, however, that a picture projected at the normal
speed of sixteen per second is too rapid for the average man unless
the object was moving slowly when photographed. It has been proved
that practice with this target improves quick-sighting and so teaches
the art of snap-shooting which is said to be the essence of modern
marksmanship. After a little experience the marksman develops the
tendency to sight instantaneously as he lifts his weapon. For training
in revolver shooting, which is essentially short-range point-blank
work, it would be difficult to conceive a better system.

Even if considered as a mere diversion the life target has many
advantages. There is a sensational realism which is lacking in the
ordinary shooting gallery. The man at the firing point is occupying the
same relative position as that of the cinematographer when he filmed
the subject, and when, for instance, a tiger is springing directly out
of the picture, the man with the gun has just the same feeling as if
caught at close quarters in the jungle. He sights and fires quickly,
hoping to hit in a vital part, and the instantly appearing shot-hole
tells him how he would have fared had he been face to face with the
animal in its native haunts.

So far as military shooting is concerned the system has its
limitations. For the reasons explained the screen cannot be more
than 100 feet from the firing line. It is a pure point-blank range.
No allowances can be made for windage or trajectory. There is yet
another factor that controls the distance between the firing range line
and the screen, and that is that paper cannot be obtained in widths
exceeding 9 feet. A single width must form the screen, since no light
must be visible from it until it is perforated by a bullet. So there
is a strict limit to the size of the target. But it is possible to get
subjects life size, and nothing more is required.




CHAPTER XVII

THE PREPARATION OF EDUCATIONAL FILMS


Although animated photography is regarded popularly as an amusement,
and the picture palace is maintained to be the poor man's theatre,
efforts are being made to lift the invention into a higher and more
useful plane. It is sought to adapt it to the schoolroom, the college
and the technical institute. Up to the present, however, little headway
has been made in this direction, though the market is flooded with
so-called educational films.

Unfortunately the attitude of the responsible authorities is lukewarm,
somewhat to the chagrin of those who are specializing in the
preparation of these films. The authorities are said to be prejudiced
against the invention, and no doubt the impression still lingers that
the cinematograph is an instrument of frivolity.

Up to a point the authorities are correct in their attitude. It is the
producer who is at fault. The former recognise the many advantages
arising from the appeal to the eye, but unfortunately the producer
looks at the question from the showman's point of view. He is not
content to prepare a subject which shall appeal only to pupils as such,
but is always trying to introduce an element which shall make the film
popular with adults as well. He seeks to arouse the enthusiasm of the
schoolroom and of the picture palace at one and the same time, though
the two are as widely apart as the two poles, and what is suited to one
is by no means adapted to the other. The patron of the picture palace
must be entertained only. Education, if any, must be unconscious.
On the other hand, the essential consideration in the school is the
training and teaching of the young mind. If amusement is introduced the
educational value of the film is liable to be small.

In this attempt to supply two different markets simultaneously many
producers over-reach themselves. They fail to realise that a schoolroom
film must be absolutely natural, that there must be no trickery or
faking. There are several films on the market to-day, aiming at the
requirements of education, wherein the most attractive incidents
are nothing more nor less than examples of fake photography. The
educational authorities are only too well aware that trickery is one
of the cinematographer's most useful tools, and accordingly many films
of an apparently astonishing character are regarded with suspicion.
Until all traces of faking and chicanery are abandoned the authorities
are certain to look coolly on the suggestion of teaching by the
cinematograph.

Nevertheless the film must be prepared in such a manner that the pupil
is not bored. It must be rendered interesting and fascinating or it
will be no better than the old Dry-as-dust teaching. And the infusion
of interest is by no means difficult. Every branch of science, every
item in the curriculum, can be taught by motion pictures. One producer
has prepared a novel and interesting film for teaching the alphabet and
the spelling of simple words with the aid of a troupe of acrobats. The
acrobats contort themselves into the shapes of letters upon the screen
before the children's eyes. The children naturally follow the process
with interest, and the finished letter at once impresses itself upon
their minds. The spelling of the words is carried out in the same way.

Another producer has a novel idea for explaining the principles of
addition, subtraction, multiplication, and division. He has devised
animated scenes with teddy bears and oranges, and the setting itself is
a schoolroom. The actors, who are children, are dressed in bear skins,
and they behave in a truly grizzly manner. The very fact that this
favourite toy is introduced rivets the attention of young children,
and they follow the arithmetical adventures of the oranges with the
utmost fascination. The bears themselves perform their parts most
decorously, without any horseplay or clowning. The youngsters following
the incidents upon the screen are induced to regard the projection
seriously, and it has been found that afterwards, in their leisure
hours, they reconstruct the incidents with their own toys. In this way
they show that they have grasped the idea that was to be conveyed.

In dealing with the sciences similar methods must be practised.
Suppose, for instance, that it is intended to teach physics, chemistry,
or electricity with the aid of moving-pictures. The film must commence
at the very beginning of the subject. The text-book should be taken
as a model. The producer of the film, if he is well acquainted with
his subject, can devise experiments to suit any stage of knowledge.
He can vary the experiment so as to bring the pupil face to face with
something which has never been illustrated by diagram in the text-book.
He can lead the pupil on step by step, and the more deeply he plunges
into a particular science the wider is his scope for the portrayal of
fascinating experiments.

[Illustration: (1) MOORHEN SITTING ON HER NEST.]

[Illustration: (2) THE YOUNG CHICK PIERCES THE SHELL.]

[Illustration: (3) THE CHICK EMERGING FROM THE SHELL.]

[Illustration: (4) THE NEWLY-HATCHED CHICK STRUGGLING TO ITS
FEET.]

The preparation of films of this character offer attractive
possibilities to the independent worker, especially if he is familiar
with teaching methods. The professional producer is often unable to
reduce his subjects to the requisite simplicity. As a rule he knows
little or nothing about a schoolroom, and the result is that he
confines himself to the preparation of extremely fascinating films of
a very advanced type, suited to the student in the secondary school
or to one who has mastered the rudiments of the science. But it is in
the laying of a solid foundation that the teacher finds his greatest
difficulty. As a rule he has to go over the ground repeatedly before
the elementary points sink into the pupil's mind. This drudgery can
be greatly reduced by use of the moving-pictures, if only the right
type of film is shown. The professional producer maintains that such
an elementary film is useless, merely because he looks at it from the
showman's point of view.

Another reason why the independent cinematographer should embark upon
this field is that he is generally more ingenious and fertile in the
preparation of experiments to suit the limitations of a lesson. He will
know how to be simple, so that the pupil, after the demonstration, can
go into the laboratory and repeat the experiments with a knowledge of
what he is doing.

As the pupil advances the films may be varied. For instance, in the
experiments with sulphur he can be shown how sulphur is obtained.
Views can be introduced of the mines and processes as practised in
Sicily or Louisiana, and in this case the difference between ancient
and modern methods can be brought home to him. Similarly in regard to
the subject of common table salt it is possible to show the various
methods of extraction, from the solar evaporating system practised in
the Caucasus and California, and the excavation of rock salt as in
Galicia, to the pumping of brine and forced evaporation common to the
"Wiches" of England. The film may be "lightened" by glimpses of bathing
in the Great Salt Lake or the brine baths of England in order to convey
pictorially the difference in the density of salt and fresh water. In
many cases it is possible to reproduce upon the screen the processes of
Nature, the character of the experiment varying with the stage of the
pupil's knowledge.

Attempts are being made to teach geography by moving-pictures, but
here again the same defects appear. Most of the so-called geographical
films are merely the "Travel Subjects" of the picture palace,--another
attempt to make a subject fit both the theatre and the schoolroom. Such
films are useless except to form a pictorial interlude in text-book
explanation. Yet there is a remarkable scope for geographical films.
Let it be assumed that the lesson is about the birth of a river.
The teacher dwells at length upon the possible sources, upon the
tributaries that increase the volume of water during its journey, upon
the navigable reaches and the traffic, and lastly upon the discharge of
the waters into the ocean.

[Illustration: (5) EXHAUSTED BY ITS STRUGGLES THE CHICK RESTS IN
THE SUN.]

[Illustration: (6) A FEW HOURS LATER THE CHICK TAKES TO THE
WATER.

The "Birth of a Moorhen." A wonderful series of moving-pictures taken
by an amateur lady cinematographer.

_From the "Cinema College," by permission of the Motograph Co._]

[Illustration: FIGHT BETWEEN A LOBSTER AND AN OCTOPUS.]

[Illustration:

 _By permission of Pathe Freres._

THE STORY OF THE WATER-SNAIL.]

Cinematographically the rise and growth of the river may be shown far
more graphically and attractively. The pupil can see every phase.
The source may be an insignificant spring, the outflow from a lake,
or the melting ice of a glacier. Its rapid growth can be depicted by
showing the inflow of its tributaries and the many sudden changes
through which it passes, its rapids and its falls, while the fact
that water follows the path of least resistance may be illustrated by
showing the evidences of erosion and the manner in which the river has
cut its channel through friable soil, or taken advantage of a breach
in a rocky rampart. At the same time the pupil can be introduced to
the utility of the waterway, especially upon its upper reaches, by
pictures of the craft found thereon and the traffic in which they are
engaged. The varying force of the current can be illustrated, and also
the flotsam and jetsam that has been brought down. Finally, gaining
the lower reaches, steam and motor navigation begins, with towns and
cities on the banks, and in conclusion the pupil may be given an idea
of the immensity of the estuary together with the life and industry at
this point. In addition some impression of the delta can be conveyed
with moving-pictures of the way in which the detritus brought down
from the upper reaches, is deposited at the mouth, forming islands and
sand-banks, clothed with vegetation, and, if not developed, inhabited
by wild fowl.

The preparation of such a film is certain to occupy a long time, and
is somewhat expensive, but these items must be disregarded if the
schoolroom is to have what it requires. A film of this character would
have to be divided into certain lengths, each of which would correspond
with a lesson, for the subject is too vast to be assimilated in a few
minutes. Cramming by the aid of moving-pictures would be worse than
under present conditions. In many cases the camera will show that
existing text-book teachings are erroneous or need modification. Some
idea of the utility of the cinematograph in this one particular field
has been revealed by the films of the Shackleton and Scott Antarctic
expeditions. They have brought home more vividly than anything else the
meaning of the eternal snow, ice and cold, associated with the Polar
regions, and they have served to dispel many false ideas.

So far the greatest success achieved by the motion-pictures in
the field of education is in connection with natural history. Many
wonderful films bearing upon animal life have been prepared and have
created sensations. The text-books tell much about the life and
habits of the various members of the animal kingdom, but in this case
the text-book often happens to be wrong. Mr. Frank A. Newman, an
industrious animal photographer, devoted months to the preparation
of a film 5,500 feet in length dealing with certain phases of animal
life. He confined his efforts to the study of those creatures which
are familiar to all. Incidentally, he proved the value that a highly
instructive film possesses in the market, for within sixty days of its
first appearance upon the screen, over L8,000 or $40,000 was realised
from the disposal of the rights to exploit the film in different
countries.

Pictures dealing with animal, bird, fish or reptile life never fail
to command high prices. Indescribable patience is demanded in their
preparation. Months may pass and yield only a few hundred feet
of suitable material, and the photographer has to resort to the
most extraordinary devices to take the subjects in their natural
environment. One worker, who set himself the task of filming the
kingfisher, discovered the haunts of his quarry, and then quietly
commenced to establish himself in its vicinity. He had to be
exceedingly cunning in his movements, masking the position he had
assumed in four feet of water, with a clump of tree boughs. Concealed
in this ambuscade he approached the bird, moving with extreme care,
so as to convey the impression that the boughs were drifting with the
stream. Behind this ambush he placed his camera, clamping it to a heavy
floating base, which was anchored. In this way he was able to move
undetected. When he thought that the time had come for an exposure, he
commenced to turn the handle, but the whirr of the mechanism scared the
bird, and he was forced to wait some time, until its courage revived
and it came back. He then mounted a second camera on the floating
base, and this, being empty of film, was set in motion every time the
bird returned, until it grew accustomed to the unusual noise. After a
few days the bird took no further notice of the sound, and then the
pictures could be taken with comparative ease. Altogether some seven
weeks were occupied in obtaining about 200 feet of film, during which
time the operator had often to stand for hours at a time in four feet
of water, awaiting his opportunities. How completely his strategy
and patience were rewarded may be gathered from the fact that in one
incident, where the bird is shown devouring a fish it has caught, it
perched upon a branch of the ambuscade, barely four feet from the lens,
completely unaware of the fact that its actions were being recorded.

[Illustration: THE HEAD OF THE TORTOISE.]

[Illustration:

 _By permission of Pathe Freres._

THE HAWK MOTH.]

[Illustration: SNAKE SHEDDING ITS SKIN OR "SLOUGH."]

[Illustration:

 _From the "Cinema College," by permission of the Motograph Co._

THE SNAKE AND ITS SHED SLOUGH.]

Another indefatigable worker is Mr. J. C. Bee Mason, whose speciality
is the filming of insect life. He has produced four films depicting the
honey bee. As studies they are intensely interesting, and they bring
out the characteristics of the subject in a most attractive manner. The
average worker might hesitate to film such a subject at close quarters.
The bee is very quick to resent intrusion and disturbance in a way
peculiarly its own. Mr. Mason himself admits that in the early days he
received very severe punishment, but he stuck to his camera and his
work with the result that in the course of time he became accustomed
to the attacks of the bees and to-day a sting has no more effect upon
him than upon a deal board. The result of this patience is reflected
in the excellence of his films which bring bee life most intimately
before the spectator. The bee is always an object of interest, and in
this particular case his films have brought Mr. Mason over L2,000, or
$10,000.

Although here and there one comes upon a film which exactly meets with
the requirements of the schoolroom, the majority can make no such
claim. They are merely instructive, in an amusing kind of way, and in
the picture palace they come as a welcome relief from transpontine
drama and buffoonery. Fortunately, at the present moment, there is a
growing tendency to make films which the schools will really welcome.
One concern is studying the situation very closely. This is the
Motograph Film Company of London, which has completed contracts with
the most prominent European scientific cinematographers for their
entire output of educational, scientific and natural history subjects.
It is also endeavouring to persuade the eminent teachers of certain
subjects to commit their work to the celluloid film instead of to
printed books. It is a difficult quest because the professors are apt
to regard the cinematograph as a joke. At the same time, once the
development becomes started upon the correct lines, it cannot fail to
meet with success.

The independent worker also is being encouraged by the Motograph Film
Company, and the cinematographic student of scientific subjects has
a very profitable market open to him. The prices paid for the films
naturally vary according to their merit, but this company is prepared
to pay from 2_s._ 6_d._ to 21_s._--from 60 cents to $5--per foot
of film for subjects which meet with its approval. The lengths may
range from 50 to 6,000 feet. Recently, an independent lady worker,
who in her spare time had given attention to filming the "Life of
a Moorhen," showing the building of the nest, laying of the eggs,
hatching and rearing of the young, submitted her film to this concern.
Some two-and-a-half years had been expended upon this subject, but
the quality and the incidents depicted were so excellent that the
1,000 feet of film was bought for L650 ($3,250). This film has proved
that the highest class of work must be obtained from the independent
worker, or amateur, if that word is preferred, for the simple reason
that time is no object, the task is not hurried, and no effort is
spared to obtain the finest results. Another instructive film bought by
this concern shows "Big Game Hunting in the North Pole Icefields." It
introduces one to the polar bear. Altogether this subject extends over
8,000 feet, but for a selected length of 1,900 feet the sum of L2,000
($10,000) was paid. In the case of another celebrated Arctic film,
taken during the two years' imprisonment of the Whitney expedition in
the frozen zone, and about 6,000 feet in length, the same company gave
L3,000 ($15,000) for the English rights alone.

Although the cinematograph has failed to make a very pronounced advance
among our educational institutions, it has proved a striking success
in education of another kind. This is in regard to the propaganda for
improving health and hygiene. This movement has reached its highest
stage of development in the United States. The "Swat the Fly" movement,
which declared a relentless war against the common house-fly, was
powerfully assisted by the exhibition of films depicting the fly at
work in the dissemination of disease. Free exhibitions have been given
throughout the United States for the purpose of bringing home to the
public the serious menace that this insect offers to the welfare of the
community. One or two of the films used for the purpose were bought
from England, where they had been used in the picture palaces. But the
organisation pledged to the extermination of the fly turned them to a
far more serious purpose, and its work has met with remarkable success.

Another series of health films bear upon the "Great White Scourge."
They are being exhibited freely and are bringing home to the public
the terrible ravages wrought by tuberculosis. The dreaded bacillus is
shown at its fell work, and the different stages of the disease are
pictorially represented. Then follow a series of photographs showing
how it is transmitted, and lastly some pictorial suggestions as to how
it may be combated, at least in its early stages, by fresh air and
sanatorium treatment.

The success of the fly and White Scourge campaigns has resulted in the
preparation of other films dealing with the public health, while many
local authorities have taken up the idea for the purpose of improving
the conditions of their localities. Many of the films used for the
purpose are prepared by amateur workers, especially when the subject is
of local importance, and their ventures are proving highly profitable.
Experience has proved in no uncertain manner that moving-pictures will
soon be the world's most powerful educator.




CHAPTER XVIII

PHOTO-PLAYS AND HOW TO WRITE THEM


The vogue of the picture palace has created a new profession. This is
the writing of plays especially for cinematographic production. In
the early days the handful of producers engaged in the craft had no
difficulties in meeting their needs in this direction. The producer
conceived and worked out his own ideas. The market was small, the
output was restricted, and it did not matter whether the plots were
good, bad, or indifferent. The public was quite content with the
dramatic fare supplied upon the screen, being more impressed by the
novelty of the performance than by its merits.

But with the rage for picture palaces the whole business underwent a
transformation. The public, having outlived the era of curiosity, and
having shown by its patronage that it regarded the picture palace in
the same light as a theatre or music hall, grew more and more critical.
It demanded stronger plots, improved mounting and acting, as well
as better photographic quality. As new firms entered the producing
field, competition became acute, and the whole photo-play industry
automatically transferred itself from the pioneer to the accomplished
master of stage-craft. The producer, unable to prepare his scenarios
himself, sought the assistance of the amateur playwright, just as the
editor of a periodical solicits contributions to fill his pages.

It was a golden opportunity for the unknown struggling dramatist.
Foiled hitherto by lack of chance, the power of the privileged few,
and the absence of enterprise displayed by theatrical managers, he
handed his work to the upstart rival, the picture-play producer. It
was a wise move. The dramatist did not, indeed, secure that measure
of publicity upon the screen which might have been his lot upon the
boards, but the financial returns were more regular. As he developed
his inclinations, and his work became appreciated, he was able to
anticipate a comfortable income, owing to the steady demand that arose
for his handiwork. To-day the embryo dramatist never bestows a thought
upon writing for the stage; the cinematograph will absorb all that he
can produce, and as rapidly as he can complete it.

No longer need a budding genius starve unknown and unappreciated in a
garret. If his work possesses any merit the cinematograph will turn it
to profitable account. About three hundred picture-plays are placed
upon the world's market every week, and consequently the consumption of
plots is enormous. What is more important from the author's point of
view is the expanding nature of this market, where supply cannot keep
pace with demand, and the proportionate improvement that is manifest
in the scale of remuneration. Ten years ago a plot seldom fetched
more than five shillings or a dollar; to-day the same material will
command anything between L5 and L50--$25 to $250. In this field of
activity reputation counts for nothing. The play and the play only is
the thing. The picture palace is the poor man's theatre, and this class
of play-goer is relentlessly emphatic in condemnation, and equally
enthusiastic in praise. It appreciates novelty in plot, and that is
the one point the author has to bear in mind. So it is clear that the
unknown playwright has everything in his favour; in fact, his work is
generally preferred to that of the skilled writer. It contains the very
best efforts of its creator; the other is probably of poor quality,
because the man with a name does not realise what the people want, and
thinks that for the cinematograph anything is good enough.

[Illustration:

 _By permission of the Motograph Co._

EXTERIOR VIEW OF THE DUMMY COW USED BY MESSRS. NEWMAN FOR TAKING
MOVING-PICTURES OF WILD ANIMALS, SHOWING DOOR AT SIDE.]

[Illustration:

 _By permission of the Motograph Co._

MR. FRANK NEWMAN AND HIS CAMERA HIDDEN WITHIN A HOLLOW TREE
TRUNK.

The utmost concealment is necessary to secure wild-life under natural
conditions.]

The desire of the photo-play producer to encourage unknown writers
has led to the inevitable result. He is inundated with plots and
suggestions of every description, written by every type of man, woman,
and child. Needless to say, a large proportion of the submitted
contributions are wildly impossible, or contain plots which have been
worn so thread-bare that there is no possible chance of dressing them
in a new guise. Fortunately the task of sifting the wheat from the
chaff is not exacting. A hurried scan of the opening lines generally
suffices to show whether the subject is excellent, passable, or
hopeless.

Picture-play writing is an art, science, or whatever one likes to call
it, which can be cultivated. The average person, at some time or other,
is sure to have an idea--it may be an idle fleeting thought--which is
capable of being turned to useful account. The picture-play producer
knows this very well, and accordingly holds out every inducement in
the hope that sooner or later he may light upon something brilliant.
A suggestion need only have some small germ of possibility, but the
producer, from his experience of the theatre, and of the requirements
of the picture palace, can take that germ and evolve it in the most
effective manner.

Under these circumstances the question arises "How should a photo-play
be prepared?" While there is no golden rule, and while each producer
works in his own way, it is possible to give a few hints to the
beginner. A glance at the manuscript is enough to inform the reader
whether the author is a raw hand at the work or otherwise, and although
every manuscript is reviewed, more interested attention is attracted by
a contribution which is set out upon more or less methodical lines.

In the first place it is just as well to remember that the photo-play
producer of to-day is a man of wide experience. In most cases he
has graduated upon the stage, and has probably passed through all
the phases between a touring company and a well-known theatre. As a
result of this drilling he will have assumed a wide perspective. Sheer
ability will have brought him to the control of the cinema-studio
stage, where the work is most exacting, and where there is a very great
demand for ingenuity and resource. Having mastered the intricacies
and possibilities of the photo-play stage, and what can be done by
photography, he will be a thorough master of craft. The greater number
of the play-producers retained by the foremost firms are men who
climbed to the top rung in the theatrical profession and merely went
over to the motion-picture studio because it offered them greater
scope for their prowess and knowledge. Indeed, one might go so far as
to say that, unless a man has served his apprenticeship behind the
footlights, he is an indifferent play-producer, because he will be
ignorant of stage-craft and the technique of the profession.

A man of such experience and ability is able to sum up the value of a
plot in an instant. Consequently the author is well advised to condense
his plot into as few words as possible--the briefer the outline the
better. In some instances it is not even necessary to indicate the
characters, the period, or the scene. The plot is the only thing that
is wanted: the producer, as he reads it, will conjure up in his mind
the period, environment, atmosphere, and characters, wherewith such and
such a story may best be worked out.

There is one well-known Continental producer who never asks for more
than a bald statement of the plot. If it can be conveyed in six lines
he is more than satisfied. On one occasion, while seated at lunch, one
of the party jestingly suggested an idea. Without a word of comment
the producer scribbled the suggestion upon the back of an envelope.
Returning to the studio an hour or so later, he handed a note to one
of his staff, indicated how he would like it worked out, the colleague
fitted in the characters, evolved the scenes, period, and situations,
and the next morning the play was staged.

One of the foremost French picture-play producers follows a
similar practice. He has a staff of eight writers whose sole duty
is the preparation of scenarios for production. Plots as they flit
through the minds of these men are jotted down and pigeon-holed. The
outside contributions which come in with every post are scanned, and
those thought suitable are dissected, their ideas are torn out and
re-committed to paper, for filing, while the author is rewarded with
payment according to the merit of his work. At this establishment no
lengthy scenario submitted by an unknown writer is considered. Time is
too valuable when eight or ten stages have to be kept going. The staff
is fully occupied upon the work in hand, and cannot wade through pages
of often indecipherable hand-writing. The method of this particular
producer in the case of an ordinary play is to have an abstract,
prepared by the retained scenario writer, indicating the scenes, their
sequence, characters, and other details, with a brief synopsis of the
plot, the whole being set out upon a sheet of foolscap. Upon this
material the producer works, explaining to the company the story of the
play and the situations, as they progress step by step.

Many producers, however, prefer the scenario to be submitted in a more
complete form, though requirements of brevity and terseness must be
observed. They like the list of characters to be given, together with
a suggested period and setting. The cast should be kept as small as
possible, as a plethora of characters in a photo-play is apt to be
bewildering. Also the producer can amplify the cast if he wishes to do
so. The plot should be set out in narrative form. A bald synopsis is
quite sufficient because the scenario expert will judge the merits of
the manuscript from this alone. In order to assist the producer the
main points and situations may be indicated. After the synopsis there
should be some suggestions for working out the story scene by scene.
These are not essential, but they sometimes give the reader a better
impression of the story, and help him in staging the play. The chances
are a hundred to one that the play never will be staged as written by
the author, yet its brief evolution is often appreciated.

When the author works out his plots he must steer clear of introducing
wild impossibilities or hopelessly impracticable suggestions. The
producer is admittedly a clever man, and is able to get wonderful
effects with the aid of the camera, nor does he hesitate to employ
trickery when it will further his purpose, but there are limitations
even to trick photography. There was one manuscript in which the
author, after taking his villain through adventures innumerable,
suggested a sensational means of eliminating him altogether. The man
was speeding across a frozen river to escape the vengeance of the hero
when the ice opened up suddenly, let him through, and then closed on
him to hide him from sight and memory. Needless to say, this plot met
with scanty consideration. In another case the plot turned upon a
lady's ring. The lady was standing by a river, and the ring slipped
from her finger into the water to be caught and swallowed by a fish.
Some days later the hero was fishing in the same stream. He had a bite,
hooked his catch, cut it open, and found the ring. It is difficult to
say who experienced the most amazement, the hero when he opened his
fish, or the producer when he read the story.

In the photo-play profession it is novelty of the plot which brings
success. The farther the author can get away from conventionality, the
bigger will be the reward. This is where the average amateur shows
deficiency. He is content to follow the footsteps of others. Again,
many photo-play writers, instead of striving to be original, prefer to
steal ideas from a novelist or short story writer. This work, needless
to say, is sheer waste of time. The producer and his staff follow the
periodicals and the publishing seasons very closely, so that it is easy
for them to detect a stolen plot. Moreover, it must be remembered that
to-day the leading producing firms have arrangements with authors,
publishers and editors, for the exclusive use of their productions.
These sources form a stand-by, as it were, to be brought into use when
the fount of original scenarios dries up. When novels and magazine
stories are to provide fare for the screen the producer entrusts the
work of adaptation to one of his staff who has a more intimate idea of
what is required, and will perform the task far more satisfactorily
than the ordinary contributor.

The photo-play author has one great advantage over his colleague who
writes for the stage. The latter has to supply dialogue, and often the
success or failure of his work turns upon this factor. In writing for
the screen dialogue is a lost quantity. It is action which is required,
because the spectator has to follow the play from what he sees, and not
from what he hears. Accordingly the requirements of action must be kept
in mind. In the average studio the actor either extemporises dialogue
to fit the part or situation, or else the producer prompts him.

It is true that one or two producers stipulate that the photo-play
shall be written out in detail as if it were to be played behind the
footlights, but such producers may be set down as incompetent or
behind the times. A few years ago one of the Continental firms insisted
that every play should be written out in full, but a few months'
experience showed the folly of this procedure. Plays mounted in this
manner lacked that grip and movement which is necessary in photographic
pantomime. The audience could not retain the thread of the story, and
the interest consequently flagged. The members of the company, being
compelled to learn their lines, and to rehearse continually, went
through their parts like puppets. Accordingly this method of mounting
and acting has been abandoned in favour of the other in which the
company, absolutely ignorant of the plot and story, is taken through it
step by step and maintained at concert pitch throughout.

The writer should make a point of selecting a striking or catchy title
for his work. Often when the plot itself is useless the producer will
buy the manuscript merely to apply the title to some other production.

A word of warning may be given to the inexperienced photo-play author.
Advertisements are freely inserted in the various periodicals offering
to teach the art of writing plays for the cinematograph, and to submit
the plots to the various producers in the manner of a literary agency.
No matter how speciously and attractively the advertisements are
written, the offers they contain should not be accepted. The author
will do best to submit his work directly to the producer and to treat
with him alone. The art cannot be taught by schools; it can only be
acquired by experience. Nor does the agency possess more favourable
opportunities for getting the work accepted than the writer himself,
while the so-called expert who maintains that he can lick a plot into
shape is merely a charlatan. If the plot is good, whether written by a
raw or a highly trained hand, it will command its price, because the
producer is no respecter of persons. Also, by treating directly, the
author comes into touch with the producer, and often learns points and
receives encouragement which cannot be transmitted through a middle man.

How is the work rewarded? This is a question which is often asked. So
far as the British market is concerned the photo-play author receives
scant encouragement. British enterprise has not risen to the level of
that of the United States or the Continent. The British firms neither
realise the value of a good plot nor the advantages of prompt and smart
business methods. Here and there may be found a firm which is keenly
alive to the value of the outside worker, but they are few and far
between. On the other hand the American and Continental houses give
an immediate decision, treat the outside contributor kindly, extend
profitable words of advice if the work is promising, and pay promptly.
A plot for which a British firm considers 10_s._ 0_d._ ($2.50) to be
an adequate remuneration will realise $25 (L5) in the American market.
The British producer will consider L1 ($5) to be a princely price for
a good plot, and so long as this impression is retained the British
photo-plays will remain inferior to their competitors. On the other
hand, the American firms deal liberally with their authors, and are
quite prepared to pay from $25 to $150--L5 to L30. Fortunately signs
of awakening are becoming evident among the British firms. Good plots,
like gold nuggets, are somewhat scarce, and one or two of the latest
and most progressive establishments now pay up to L10 ($50).

Picture-play producers are finding greater and greater difficulty in
obtaining first-class plots. The standard of excellence has been set
so high, owing to the extremely critical character of the picture
palace patron, that the highest work only now stands a chance of being
accepted. The rivalry among the producers has become keen, because a
strong picture-play can command a world-wide sale. One Italian firm, in
the effort to forge ahead of its competitors, went so far as to offer
a prize of L1,000 ($5,000) for the best scenario in open competition.
It is admitted among the manufacturers that within the course of the
next few years the royalty system must come into operation, so that the
photo-play author will be elevated to the level of his confrere writing
for the theatre.

In France a society has been founded for the protection of photo-play
writers. This organisation protects its members by securing higher
rates of payment, by introducing the work of beginners to the
film-producers, and last, but not least, by advertising the writer.

Ten years ago the picture-play author was regarded with disdain, and
was considered to be little more than an indifferent literary hack.
To-day he is regarded as a powerful force. From the lowest and most
ill-paid level he is rising to the highest rungs, where his rewards are
excellent and his opportunities unbounded.




CHAPTER XIX

RECENT DEVELOPMENTS IN STAGE PRODUCTIONS


Although the mounting and staging of photo-plays has been greatly
improved, the art has still many imperfections. This is partly due
to the conservative character of the industry. There is a lack of
initiative and enterprise; the producers are content to keep in the one
groove which was established years ago. No one can deny that enormous
sums of money are expended upon the mounting of the productions, nor
assail them from the photographic viewpoint. But there is a lack of art
which at times is sadly jarring.

This was to be expected. When the English pioneers embarked upon the
play-producing business they knew nothing about stage-craft. Their
ambition was rather to perfect the photographic quality of the films.
So rapidly did the movement advance, however, and so insistent was the
public in its demands for better, larger, and more lavishly staged
plays, that the pioneer found himself out-distanced. At this juncture
came the man who had won his spurs in the theatre, and who was
thoroughly expert in the technique of stage-craft. His professional
knowledge lifted the art out of the hands of the pioneers, who retired
from the scene.

The introduction of the professional element commenced in France, and
was taken up immediately by the Americans. These two countries went
ahead so rapidly that Great Britain was soon left behind. The world
became flooded with French and American productions, and in this
healthy race the latter soon went ahead and took premier position.
The French industry, being threatened, pulled itself together, and
taking a cue from American methods it overhauled its organisations and
increased its expenditure, with the result that it soon attained the
level of excellence achieved by the United States. At a later date the
Italian industry, which was in a languishing condition, followed suit.
Money was sunk in the enterprise, huge studios were built, and talented
artists were engaged to act before the moving-picture camera.

Great Britain lagged in this race, and it is only recently that the
British producers, by a change of method have been able to make up
the leeway. The British movement was rather of a sporadic nature. It
was left to one or two enterprising firms to show the way. But others
have followed, and to-day there is the keenest rivalry in producing,
nor is expense considered so long as the public gets what it wants. To
sink L3,000 ($15,000) in a single production has become quite a common
venture.

In many cases, however, in spite of these changes, photo-plays still
follow the lines that prevailed ten years ago. The blemishes, defects,
and anachronisms are just as pronounced now as they were then, though
they are suffered in silence by the public. Many faults are hidden by
the gorgeous and lavish mounting of the scenes, while the rapid action
of the players serves to distract attention from the shortcomings of
the environment. But the feeling of actuality, which ought to be the
great feature of the cinematograph, is missing. The scenic accessories
might be left out for all the effect that they produce.

As a matter of fact the photo-play stage occupies to-day the position
of the theatre twenty years ago. The scenery is for the most part
make-shift, crudely painted in the neutral black and white, the stock
room being ransacked to discover pieces of canvas to fit the situation.
There is no attempt to create an artistic effect. Also there is an
entire absence of reality or individuality. A cell scene, for instance,
bears every sign of being built of canvas and battens, and so does the
exterior of a mediaeval castle, or the inside of a conservatory, and
completed by a factory hand.

[Illustration:

 _From the "Cinema College," by permission of the Motograph Co._

TREE LIZARD, WITH A SPIDER, WHICH IT HAS CAPTURED, IN ITS
MOUTH.]

[Illustration:

 _By permission of Pathe Freres._

THE DIGESTIVE ORGANS AND EGGS OF A WATER FLEA.]

[Illustration:

 _By permission of Pathe Freres._

THE MOVING-PICTURE NATURALIST AND THE LIZARD AT HOME.]

Sometimes the shortcomings of the studio-stage are avoided by setting
the plays in an outdoor surrounding, and in this instance a far more
realistic effect is produced. The audience is unconsciously carried
away. This has been specially realised by some of the American, Danish
and Italian firms.

In France the Gaumont Company has shown equal enterprise. So far as
possible the elaborate productions of this company are acted in a
scene suited to the plot, whether it be a sixteenth century castle or
a modern hotel. There is ample opportunity for doing this, and the
present popularity of the photo-play proves the wisdom of the policy.
During the summer months as many as six different companies will be
working in as many different corners of Europe, acting plays in the
open air for the picture palaces. Even the interiors in Gaumont films
are often real and not merely constructed for the occasion. As a rule
the studio is used only during the winter when the climatic conditions
are unfavourable for outdoor work. This is the chief reason why the
Gaumont films to-day are in such demand, and why the company has forced
its way to the front.

The conveyance of players to a suitable natural setting is expensive,
but it represents all the difference between success and failure. Of
course, there are occasions when a natural setting demands a certain
amount of artificial embellishment. This was the case in the filming
of Hamlet, as presented by Sir Forbes Robertson and his company. A sea
background and a battlemented castle were required. The former was
quite easy to find, but the combination of the two was more difficult.
The problem was solved by the choice of Lulworth Cove as the scene
and by erecting a solid set to represent the castle. In this case the
preparation of the extemporised castle was so thorough and careful that
it looks like a weather-beaten stone building.

The photo-play stage will be forced to emulate the current practice
of the theatre. It must bring the artist to bear upon the work. At
the moment it is merely a combination of the photographer and the
stage-manager or producer. The latter is not always an artist, though
he is clever at making existing facilities suit his purpose. The
theatre is holding its own principally because it respects the artistic
side of the issue. Individuality is encouraged. The photo-play stage
will have to follow the same line of action. Directly this is done the
picture palace will become a spirited rival of the theatre.

For this reason the efforts of Sir Hubert von Herkomer, the eminent
British artist, are being followed with interest. He was attracted to
the photo-play producing business owing to the artistic atrocities
perpetrated by the professional producer of film plays. He is not
attempting to achieve any revolution, except in the mounting and acting
of plays for the camera, but in this sphere he hopes to bring about a
recognition of the part that the artist must play.

There is a complete absence of sensationalism about the
artist-producer's work, and in this respect he goes against the
conventions. He is deliberately flouting many of the accepted tenets
of the photo-play production, and his attitude is certain to meet
with some hostile criticism. But from the realist point of view he is
correct. His matter-of-fact productions give verisimilitude to the
scene and story, and brings them within the range of probability. There
is no straining after effect. No detail is introduced unless it has a
distinct bearing on the subject. The costumes are faithful to the last
button. If a sixteenth century farmhouse is wanted, it is built, and
built so well that in the picture it has every appearance of having
been built of stone.

A feature which will be appreciated in the Herkomer productions is the
suppression of the harsh and distressing blacks, greys and whites,
which under brilliant illumination often convey the impression of snow.
Nor do the players seem to be suffering from anaemia. These appear to
be trivial matters in themselves, but they greatly affect the ultimate
whole. The robust aspect of the peasant who lives out of doors is
faithfully conveyed, and he is thrown up in sharp contrast to the
white-faced townsman. In the conventional picture-play, on the other
hand, there is no individuality of facial expression, because one and
all are made up in the same way.

Sir Hubert von Herkomer has commenced his work in a logical way. He
confesses that until he began it he knew nothing about it. He was
not harassed by a partial knowledge of how things are done. He is
essentially a pioneer, content to work out his own ideas, and possessed
of views upon stage-craft which are not to be despised. They had a good
effect upon the theatre twenty or thirty years ago, and have lately
been revived by another enthusiast. So Sir Hubert von Herkomer is not
likely to be the slave of tradition.

He maintains that in the average photo-play everything is sacrificed
to rapid action. This is true, and it is done purposely to distract
attention from the weakness of the rest. The spectator must fix his
attention upon the characters or he loses the thread of the story. No
time is given him to see the deficiency of atmosphere or environment.
The result is that everything is rushed through as if the villain and
hero were racing the clock. To realise this it is only necessary to
follow the film-play of a well-known historical story. Familiarity with
the incident here gives the spectator a chance of taking in the setting
and the mounting. If there are mistakes, interest gives way to mirth
and all concentration is lost. The picture is followed with no more
enthusiasm than a pantomime. This is the main reason why producers are
chary of portraying well-known historical episodes upon the screen.
One educational authority has described such films as burlesques, and
that is among the causes of opposition to the cinematograph as an
educational medium. In one instance an attempt was made to film an
incident in one of Fenimore Cooper's stories with white actors made
up as Red Indians. It was acted in a well-kept private forest instead
of in the wild woods of Canada. But young and old proved to be too
familiar with this author's works. They had too true a notion of the
Canadian timber wilderness to be impressed by the substitute on the
screen, and received the presentation with the ridicule it deserved.
The sight of a Red Man slouching through the bush with out-turned feet
and trying to conceal himself behind a tree less than six inches
in thickness, proved to be merely comic. But other things equally
ridiculous are found in many of the films of to-day, and that is the
reason why the scenes are so judiciously rushed.

By slowing down the speed of acting, though without reducing the
sustained interest, Sir Hubert von Herkomer contends that the public
will be put in a position to grasp the whole subject, and will be able
to follow it more rationally and comprehensibly. At the same time the
players will have time and scope to perform their parts properly.
There is not the least reason why this should not be achieved without
allowing the action to flag or the interest to drop.

The lighting of the subject is another important feature to which
Sir Hubert von Herkomer is giving attention. The illumination must
be arranged to suit the situation, and as cinematography offers
the utmost latitude in this respect, it is unnecessary to rush to
violent extremes. In many productions the studio stage is suffused
with such an intense glare that all facial expression and shadows
are sacrificed. Sir Hubert has realised how great is the scope for
improvement in this direction, and is altering the whole principle
of stage lighting. Similarly, in outdoor work he is supplementing
sunshine with arc lights, so as to secure the steady illumination
necessary for good effects. The combination of brilliant daylight and
artificial illumination is a novelty in photo-play production, but when
the action is taking place under trees, where the shadows are heavy and
in sharp contrast with scattered patches of brilliant sunlight, the
players are apt to present a phantom appearance. Sometimes they are
scarcely distinguishable. The introduction of auxiliary light relieves
the shadowy places and softens the general effect. Needless to say
the manipulation of powerful arc lights under such conditions demands
skilful handling, but in the Herkomer films the improved results
certainly show that the labour is not wasted.

Whether the combination of artist and producer will prove successful
time alone can show. There will be a certain amount of commercial
opposition, lacking in artistic feeling, and hostile to innovation. But
the appearance of the artist and his resolution to work out his schemes
logically should surely be encouraged by the public. The same reforms
that changed and improved the theatre, enabling it to hold its own
against the all-conquering picture palace, have a mission to the latter
also. They can lift it to the higher level that is its obvious destiny.




CHAPTER XX

WHY NOT NATIONAL CINEMATOGRAPH LABORATORIES?


Considering the position which the motion-picture has attained in our
social and industrial life, the establishment of national cinematograph
laboratories appears not only to be opportune, but necessary. At the
present moment, if one conceives an idea for the solving of some
abstruse problem by means of animated photography, one is handicapped
by the lack of opportunity and facilities for carrying out the work.
Either the apparatus required must be made specially, or purchased,
in which case heavy expenditure may be incurred, or, one must go to
Paris and make use of the Marey Institute, either by becoming a member
of it or by serving as the representative of a contributory society.
There, one is able to pursue the line of study quietly, easily, and
economically, and, even if the ultimate results are disappointing, or
the cherished theories prove to be untenable, certain benefits are sure
to accrue from the experiments. The time is not wasted.

The Marey Institute is unique and wonderful. Its operations are
world-wide. Its founder, Dr. E. J. Marey, was a prodigious worker who
pursued his scientific investigations without any idea of personal
gain. When first he entered the arena of science he began his
experiments in a large room upon the fifth floor of a house in the Rue
de l'ancienne Comedie, Paris, which formerly belonged to the Comedie
Francaise. Here he fitted up as good a laboratory as he could afford,
dividing the spacious apartment, by wooden partitions, into working
and living rooms. His studies soon aroused widespread attention, and
their results were subsequently embodied in his classical work, "The
Graphic Method." But some ten years before this volume appeared his
investigations had received recognition. In 1867 the Minister of
Public Instruction offered him the use of a laboratory at the College
of France, so as to be able to carry out his researches to better
advantage.

During this period he invented numerous instruments--the sphymograph,
cardiograph, pneumograph, thermograph, and odograph--with which he
made invaluable contributions to scientific knowledge. It was Konig's
work which attracted Marey to animated photography, as a handmaid of
science, the outcome being his greatest discovery, which he named
chronophotography. Marey was much impressed by Jannsen's astronomical
revolver with which, in 1873, a series of photographs of the transit
of Venus were taken in 70 seconds. This caused him to build a
photographic gun, with which gulls in flight were secured. The work of
Muybridge, the English investigator residing in San Francisco, aroused
his enthusiasm to the highest pitch, and enabled him to perfect his
system of taking a series of successive photographs upon a single glass
plate. Finally, in 1893, he produced his first moving-picture camera
working with celluloid films.

But some twenty years before this last achievement he had conceived
the idea for an International Institution where experiments of this
character, in connection with motion photography, might be carried out
to the advantage of the sciences. He realised that the elucidation
of physiological phenomena was quite beyond the capacity of a single
individual. He outlined his scheme at the Fourth Physiological
Congress, held at Cambridge (England) in the early seventies, while
Monsieur H. Kronecker, of Switzerland, a great admirer of Marey's work,
who succeeded to the presidential chair of the Institution after the
founder's death, urged a similar plea at an exhibition of scientific
apparatus held in London in 1876.

[Illustration:

 _By permission of the Motograph Co._

A NOVEL "HIDE" CONTRIVED BY MR. J. T. NEWMAN WITH CAMERA FIFTEEN
FEET ABOVE THE GROUND.

The working platform is covered with boughs so as not to alarm the
forest life being cinematographed.]

[Illustration:

 _By permission of the Motograph Co._

THE "HIDE" OPENED TO SHOW WORKING PLATFORM, TRESTLE SUPPORT,
OPERATOR AND CAMERA PLACED FIFTEEN FEET ABOVE THE GROUND.]

Marey's broad-mindedness met with its reward. With the assistance
of private friends and contemporary scientific societies throughout
the world he obtained adequate funds for the establishment of the
Institution, the necessity for which he had advanced so vigorously.
The City of Paris gave valuable help by granting the use of a tract of
land attached to its physiological station, and here Marey established
a commodious building with spacious workrooms, a library, lecture
hall, and other conveniences, for the profitable prosecution of
cinematographic research.

Since the foundation of the "French Cradle of Cinematography,"
innumerable and valuable contributions to scientific knowledge have
been made by investigators of all nationalities, who have gone to Paris
to take advantage of the facilities offered. Many extraordinary films
dealing with the various branches of science have been prepared. Many
of the most prominent scientists of all nations, France, Great Britain,
Germany, Italy, Roumania, Switzerland, the United States of America,
are numbered among its members.

It may be said truthfully that the Marey Institute has anticipated
all the great developments that have been made during recent years
concerning the instructional or informative side of film production.
Unfortunately the original investigations were made so long ago, before
the possibilities of animated photography were appreciated, that they
have been forgotten by, or are unknown to, the present generation. Many
an inventor, enthusiastic about a development which he has perfected
in the art, has received a rude shock when his work became public and
he learned that he had been forestalled years before at the Marey
Institute.

Nearly all of the so-called scientific films, which arouse widespread
interest to-day, were prepared originally at the Marey Institute. The
combination of the cinematograph with the microscope, the X-rays, and
other apparatus, the recording of the growth of plants and animals, the
photographing of rapid movements all these were demonstrated at this
establishment a generation ago.

Surely what has been possible at a French establishment is not beyond
the resources of other countries? When one recalls the valuable
assistance given to science by the French Institute, there should be
no hesitation in other countries to emulate the idea, and to establish
national institutions for a similar purpose. Animated photography is
still in its infancy. Its educational and scientific possibilities
are scarcely yet realised. There were many years during which no one
realised the full advantages of ordinary photography in the provinces
of investigation and experiment, and animated photography is passing
through a similar phase. This is largely because of the showman, who is
enterprising, and has captured the fort for himself. Probably no other
industry has been responsible for the creation of so many millionaires
in so short a period, yet there is no industry which can render so
great a service to science.

It should not be difficult to establish national institutions, on
Marey's lines, in every country which has great industrial and
commercial interests at stake. So far as Great Britain is concerned it
might be attached to the National Physical Laboratory at Teddington.
This establishment has an extensive array of scientific apparatus of
all descriptions capable of being utilised in conjunction with the
moving-picture camera, so that the additional outlay would not be
excessive. Not only would it be possible to utilise the invention in
connection with existing experiments, but independent and original
investigation could be undertaken. There are many points of science
which can be determined only by moving-pictures. Although Marey
covered the ground very completely during his lifetime, as a perusal
of "Movement" will show, many new spheres of application have appeared
since his time. It is quite possible that if some of his investigations
were repeated in the light of later knowledge, the new results would
be quite as striking as the old.

In Germany the cinematographic laboratory might be attached to the
world-famed testing laboratory at Charlottenburg. At present, although
the recording instruments in use are of a most modern and perfect
description, there are innumerable instances where improvement might
be effected by photographic methods. The German military authorities
were not slow to appreciate the value of Professor Cranz's system of
photographing projectiles in flight. Directly the initial experiments
were concluded the work was taken up by the War Department. Although
certain particulars of the apparatus employed and its method of
operation have been published, the essential details have been kept
secret. It is admitted that the method evolved by Cranz is imperfect
in certain features, but the authorities have the germ of a useful
invention, and are now developing it independently. In Italy also the
value of the cinematograph is being appreciated in a certain direction.
The Minister of Marine has established a special department of
photography and cinematography in Rome, after personal investigation of
the utility of the invention during the naval manoeuvres.

The United States of America has been no more progressive than Great
Britain in giving recognition to animated photography, but there
are indications that this lethargic attitude is to be abandoned.
Certain influential interests have suggested the establishment of a
cinematographic bureau of standards, emphasising the usefulness of the
invention for supplying measurements of time and work. Apart from this
movement other independent enthusiasts have recommended the formation
of moving-picture laboratories in connection with the various training
institutions, so that students might be trained on the correct lines.
Doubtless the perfection of continuous-record cinematography, and of
cameras capable of working at the highest speeds, will stimulate the
movement, for they provide a method of getting information which even
the cinematograph has not hitherto been able to give.

There are a thousand problems incidental to industry and commerce
which now defy solution, but could be solved by animated photography.
Aviation, which at present is occupying the attention of every nation,
is a case in point. The mechanical part of the science has been
investigated minutely but little progress has been made in studying the
effect of the air upon the planes, so as to discover the best forms of
cutting edge. Present endeavour is content to work upon the results
obtained by Marey with his chronophotographic apparatus some twenty
years ago. No attempt has been made to ascertain whether it is possible
to improve upon his work, or to determine whether the data he gathered
is in need of modification. Another field of investigation is in regard
to the testing of metals, woods, and other materials, to discover their
behaviour under varying degrees of strain.

A national cinematographic laboratory need not be expensive either to
establish nor to maintain. The Marey Institute might be taken as a
model. After the death of Marey, in 1905, the means of carrying on the
institution were completely reorganised. The work it was accomplishing
was recognised as being too valuable to be allowed to cease. The
French Government took up the question and decided to grant an annual
subvention of L960 ($4,800). The German, Swiss, Russian, and other
Governments, as well as various scientific institutions of all nations,
also decided to subscribe regularly to its support. In this way, with
the addition of some private subscriptions, about L1,500 ($7,500) is
contributed annually. Other contributions are made in kind, such as the
film, all of which is given by the firm of Lumiere.

Considering the work accomplished by the Marey Institute it is
maintained very economically. The annual expenses average about L1,200
or $6,000. The paid staff comprises the assistant sub-director and
an assistant, two highly skilled mechanics, and one or two minor
officials, the important posts being filled honorarily.

Private investigators are encouraged to use the Institute and its
equipment. The scientific institutions of the different countries
are given certain facilities in return for a small payment. Thus an
annual subscription of L40 ($200) entitles the representative of an
institution to the widest use of the laboratory. He is not only given
free and unrestricted use of all the apparatus, but is provided with a
bedroom, so that his expenses are reduced to disbursements upon meals
and other personal requirements. Everything requisite for his study,
as well as accessories, such as light, film, developers, etc., are
provided free of charge.

The laboratory is well provided with all sorts of appliances. There
are cameras of various designs adapted to special classes of work,
dark rooms for developing, rooms for experiments, a workshop with
skilled mechanics, a library stocked with literature bearing upon
cinematography and its relation to the sciences, and a large and lofty
hall furnished with a projector and screen. As the Institute stands in
its own grounds of over 3,000 square yards, there are ample facilities
for out-door investigations.

The experimenter at this Institution has advantages placed at his
disposal which will not be found elsewhere in any other part of the
world. The majority of the appliances have been designed by the
staff mechanics, and in their manufacture extreme ingenuity has been
displayed. Much of the apparatus might possibly provide an income in
the form of royalties if it were commercially exploited. But it is a
rule of the Institute that no instrument may be patented. Its work is
for the benefit of all.

Undoubtedly the near future will see the foundation of national
cinematographic laboratories in some form or other. The value of
animated photography is not yet appreciated. Directly the sciences
realise its significance, and see that it constitutes an indispensable
aid to investigation and research, the invention will be given the
recognition it deserves. Then it will be turned into more useful
channels than at present. Individual investigation will be encouraged,
and discoveries more wonderful than any of which we know will be made.




INDEX


  Aeroscope, the, hand camera, 55-57

  Aldrich, Mr. J. G., and the use of micro-motion, 176

  Alpha camera, 22-23

  Aurora Borealis, attempt to film the, 186

  Automatic cameras. _See under_ Cameras.


  Bruce, Colonel, study of sleeping sickness, 195

  Bull, M. Lucien, optical illusions explained, 96-107;
    experiments with a bee, 119-120;
    continuous-record camera, 137;
    study of ballistics, 190


  Cameras, automatic, 54-59;
    cost of, 7-10, 22-24;
    directions for use, 35-50;
    hand camera, 50-53;
    high speed cameras, 109, 112-116, 118-120;
    mechanism explained, 25-34

  Cardiograph, the, 249

  Carvallo, M. M. J., 147-148;
    apparatus described and illustrated, 149-152;
    scientific experiments, 154-156

  Chronophotography, 136-146;
    discovery of, 249;
    the chronoscope, 111-112

  Chronoscope, the, 111-112

  Cinematography--
    (_a_) for the amateur, attractions and opportunities,
          1-12, 21-34, 92-93, 125, 133-134, 212-213, 220-221;
          picture plays, 225-237
    (_b_) scientific value of. _See_ Scientific investigation.
    (_c_) Educational value. _See_ Educational films.
    (_d_) in conjunction with the X-rays. _See_ Radio-cinematography.
    (_e_) in conjunction with the microscope.
          _See_ Micro-cinematography.

  Claw, the, 26-27;
    movement described, 29-30;
    single claw, 31

  Comandon, Dr. Jean, 147-148;
    system described and illustrated 157-160;
    investigations with ultra-microscope described and illustrated,
      168-172, 195

  Continuous records. _See_ Records, continuous.

  Cooke lens, 23

  Cranz, Dr., of Berlin, military academy, 109;
    apparatus invented by, 190-193, 254

  Crookes' tube, 153


  Dallmeyer lens, 23

  Dastre, Dr., of the Sorbonne, 172

  Demeny, Georges, 143;
    investigation with the continuous record, 144-145

  Developing. _See under_ Film.

  Driving gear, 31-32

  Drum, the, 76


  Eastman Company, stock, 63, 78;
    developing solution, 70

  Educational films, 209-223

  Einthoven, Professor (Dutch scientist), 137;
    chronophotography, 142

  Equilibrator of hand camera, 56

  Experiments and investigations: study of bacteria, 168-172;
    filming of a bee, 219;
    with continuous records, 140-145;
    study of functions of digestion, 154-156;
    flight of projectiles, 191-193;
    filming of a kingfisher, 217-218;
    in micro-motion, 177-180;
    by an ophthalmic surgeon, 193;
    growth of plants, 124-129;
    technical, 187, 188-189.
    _See also_ Scientific investigations.

  Exposure, length of, 43-47


  Film (unexposed), cost, 12;
    description, 11;
    developing, 65-74, 78;
    drying, 75-77;
    Eastman stock, 63;
    fixing, 74-75;
    the indicator, 42;
    loading the box, 35-37;
    matt film, 38-39;
    threading, 28-29 (ill.), 39-41;
    printing, 79-93;
    special for Carvallo apparatus, 153;
    winding, 77

  Film jointer, 37

  Film-pictures: prices, 5-7, 217-221

  Fixing-bath, formula, 74

  Focus-lamp, 89

  Focussing, 30-31, 38;
    effect of length of exposure, 47

  Formulae: Eastman developer, 70;
    restrainer for over-exposed films, 71;
    fixing bath; 74;
    soaking solution, 75

  "French Cradle of Cinematography," 251

  Fuechs, Dr. Otto, investigations, 188-190


  Gate, the, described, 29

  Gaumont, Company, picture plays, 241

  Geneva stop movement, 26

  Gilbreth, Mr. Frank B., 143;
    micro-motion study, 175-184

  "Graphic Method, The," book by E. J. Marey, 249

  "Great White Scourge, The" (film), 222

  Gun, photographic, 250


  "Hamlet," filming of play, 242

  Hand camera. _See under_ Cameras.

  Health films, 222-223

  Herkomer, Sir Hubert von, and picture plays, 243-247

  High-speed cameras. _See under_ Cameras.


  Illuminant, 130-132, 190;
    in micro-cinematography, 167, 170

  International Institution for Cinematographic Research, 250-251.
    _See also_ Marey Institute.

  Interrupter, 158-159;
    of Cranz apparatus, 191

  Iris diaphragm, use illustrated, 45;
    table of stops, 46-47


  Jannsen's astronomical revolver, 249-250

  Jury autocam, 58-59

  Jury duplex, 80;
    printing apparatus, 82-85

  Jury outfit, 10


  Kearton, Mr. Cherry, jungle pictures, 5, 53;
    use of aeroscope, 55


  Lens, the, 23-25;
    iris diaphragm, 43-47;
    for radio-cinematography, 160

  "Life of a Moorhen" (film), 221

  "Life Target, the," apparatus, 201-207

  Lumiere Brothers, 172, 256


  Marey, Dr. E. J., 111-114, 249-250;
    physiological research, 195

  Marey Institute, founding of, 248-252;
    later development, 256-258;
    micro-cinematography, 166-168;
    radio-cinematography, 147-156;
    slow-movement records, 125-130

  Mason, J. C. Bee, films of insect life, 219

  Matt film, 38-39

  Mechanics and cinematography, 187-190

  Micro-cinematography, 161-173

  Micro-motion study, 174-184

  Military value of cinematography, 197-208

  Motograph Film Co., educational films, 220

  "Movement," book by E. J. Marey, 185

  Movement, intermittent, 26-31

  "Movies," the, 22

  Muybridge, investigator, 250


  National Cinematographic Laboratories, a plea for, 248, 252-256

  National Physical Laboratory at Teddington, 253

  New England Butt Co., 176-180

  New Era camera, 22

  Newman, Mr. Frank A., 217

  Nogues, M. M. P., camera described and illustrated, 114;
    claw motion device, 153


  Odograph, the, 249

  "One-turn-one-picture," principle, 125, 133

  Optical illusion, 13-14;
    illusions described and explained, 95-107

  "Out-position" of claw, 29

  Over-exposed film, restrainer for, 71


  Paterson and Musgrave, Messrs., 198-201

  Pathe Freres, 156, 169

  Paul, Mr. Robert, 26

  Persistence of vision, law of, 14, 122

  Photographic gun, 250

  Photo play. _See_ Picture play.

  Physiological Institute, Paris, 195

  Picture palace as illustrated newspaper, 2

  Picture play, 224-226;
    hints on construction, 227-234;
    warning to amateurs, 234-235;
    commercial value, 235-237

  "Pin" frame, 67-68 (ill.)

  Pneumograph, the, 249

  Printing, 79-93

  Proszynski, Kasimir de, 54-55

  Punch, the, 42

  Radio-cinematography, 147-160

  Rainey, Paul, 9

  Rapid movement, record of, 108-116;
    projection of, 117-122

  Records, continuous, 136;
    apparatus, 137-138;
    scientific experiments with, 139-146

  Reinforced screen, 158

  Revolver, astronomical, 249-250

  Ries, Dr. J., investigations, 168

  Robertson, Sir Forbes, in picture play, 242

  Ross lens, 23

  Ruby light, the, 68


  Scientific investigation, 185-196.
    _See also under_ Experiments and investigations.

  Slow movements, record and projection of, 124-133

  Soaking solution formula, 75

  Speed, photographic and projecting, 16-20;
    slowing down, 108-123;
    speeding up, 124-134

  Spitta, Dr., 164

  Spoolwinder, 77

  Sprocket, 28 (ill.)

  Stock, 34

  "String" galvanometer, 137

  "Swat the Fly," health film, 222


  Thermograph, the, 249

  Time registration, tuning-fork, 103-107;
    chronoscope, 111-112

  Trick films, difficulties of, 6

  Tripod, 32-34

  Tuning-fork control, 103-107


  View finder, the, 49


  Williamson, Mr. James, 24;
    micro-cinematographic studies, 164

  Williamson outfit, 10;
    camera, 8, 24-28 (ill.);
    printer, 80, 85-87 (ill.);
    focussing, 30, 38, 47;
    mounting, 31;
    driving gear, 32;
    iris diaphragm, 43-46


  X-rays and cinematography. _See_ Radio-cinematography.


  Zeiss-Tessar lens, 23-24, 43


BRADBURY, AGNEW, & CO. LD., PRINTERS, LONDON AND TONBRIDGE.




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Transcriber's note:

Page 198 "fusilade" changed to "fusillade". (As the paper became
perforated under the fusillade it was rolled up.)

Inconsistent use of "Moor-hen" and "Moorhen" was standardised to
"Moorhen".



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