Modulus arithmetic clocks p226,227

[stanmoore]

A little pedantic or anal as you prefer but the clocks on p226,227 shouldn't actually have 12 on them doing mod 12 arithmetic it would be more correct to use 0 otherwise 12 mod 12 would be 12 which is certain to cause demons to fly out of the noses of any mathematically inclined readers.

[robconery]

That's a very, very good point. I'm going to leave this open for now... the hard part is that since I'm using the idea of a clock it's kind of hard not to have 12 at the top. Perhaps I can add wording to that effect?