P.S. Someone asked me yesterday what the Latin root of the word "sine"
was. That reminded me of Steve Schwartzmann's wonderful (and relatively
new) little book through MAA "The Words of Mathematics." I looked up
"sine" and found the fascinating history of how this resulted from
translations of misspelling from the Arabic.
Anybody have any insight into my re-Christmas question of why we have
the convention of measuring angles in trig counterclockwise from positive x
axis rather than as in navigation clockwise from north?