Mathematicians Of The Day

13th May

On this day in 1673, James Gregory wrote to John Collins about diffraction:-
If ye think fit, ye may signify to Mr. Newton a small experiment, which (if he know it not already) may be worthy of his consideration. Let in the sun's light by a small hole to a darkened house, and at the hole place a feather, (the more delicate and white the better for this purpose,) and it shall direct to a white wall or paper opposite to it a number of small circles and ovals, (if I mistake them not) whereof one is somewhat white, (to wit, the middle, which is opposite to the sun,) and all the rest severally coloured. I would gladly hear his thoughts of it.

Click on for a poster.

Quotation of the day

From Stan Ulam
Any good idea can be stated in fifty words or less.