Things that make you go "huh?"

A composer, studio owner, author, player of keyboard and bass, signed to RCA records... named Josquin des Pres. Now, that's chutzpah.

Dream diary for math geeks

I was visiting a foreign country, meeting the locals, walking along the beach, watching a bicycle race... but the thing I remember most about the foreign country is that they had a different number theory. The only sets that existed were those that we would say have power-of-2 cardinality; there was no "successor" function, but only a "twinning" function in which every element of a set is replaced with two copies of itself. Now, of course, there were occasionally three or five of something, and the inhabitants knew that, but they considered such sets to be not really legitimate, as one can't perform even the most basic mathematical operations on such a pathological set.

Oh, and they did have real numbers, to handle continuous measurements (e.g. how far up or down the beach the waves came); there was just nothing corresponding to what we call the (non-power-of-2) integers.

USEFUL math this time

So suppose you were trying to make the curved-top sleeve of a 14th-15th-century shirt, smock, dress, pourpoint, etc. (And how many of my friends-list aren't doing that this week?) You've got a measurement from the top of the sleeve to the wrist, and a measurement from the armpit to the wrist, and the difference between these measurements is the height (trough to peak, i.e. twice the amplitude) of the curve. You've also got an armscye that the sleeve needs to fit into, which means the length of the curved top (after deducting seam allowances) has to match the length of the armscye (ditto). So, given the width of the fabric and the height of the curve, how long will the curved top be? Even better, given the height of the curve and the length of the armscye, how wide should the sleeve top be?

( math stuff )

So now I know that, and next time I can just use the straight-line approximation.