15th November 2006, 11:19 AM
I just looked at it with careful measuring like you suggest, and you're right. It does curve, ever so very slightly. Not nearly as much as that illusion might lead one to believe though.
"On two occasions, I have been asked [by members of Parliament], 'Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?' I am not able to rightly apprehend the kind of confusion of ideas that could provoke such a question." ~ Charles Babbage (1791-1871)