Who was in potential peril by going to the edge?
Billy
Is he human?
no
what is he?
a horse
what is he attached to?
a wagon
What happened to the back part of the wagon?
the rear wheels went partly  down the slope.
Who was trying to stop that going further?
Andy
anyone else?
Matt
Was the animal cooperative?
no
who tried to keep ahold of him?
Andy
what did he grab on to?
the bridle
was the horse normally cooperative?
yes
Could Andy make him cooperate by holding on?
no
What did Matt do first to assist?
Tyed the lines
What had caught his visual attention?
He saw a loose stone
was it nearby or far away?
close at hand
did he touch it?
yes
where did he sprint to with it?
the rear of the wagon
where did he place it?
on the sloping ground
what did it prevent from happening?
further slipping
were they on a flat road or a high ground?
no