16th December

On this day in 1861 Weierstrass, who for twelve years had endured painful attacks of vertigo, suffered a complete collapse of his health due to overwork. Henceforth, he always lectured while seated, consigning the blackboard work to an advanced student. Nevertheless, he eventually became a recognised master teacher.

The postage stamp of one of today's mathematicians at THIS LINK was issued in 2009.