Mathematicians Of The Day

20th August

On this day in 1638 William Oughtred wrote about his slide rule invention to the instument maker Elias Allen:-
I have here sent you directions (as you requested me being at Twickenham) about the making of the two rulers. ... would gladly see one of [the two parts of the instrument] when it is finished: which yet I never have done.

Click on for a poster.

Quotation of the day

From Fred Hoyle
There is a coherent plan in the universe, though I don't know what it's a plan for.