Leonhard Euler, a Swiss mathematician who continued to work on complex equations from memory even after he went blind, is honored in Monday’s Google Doodle on the 306th anniversary of his birth. Euler ...

Philosophical Transactions (1683-1775) Vol. 46, 1749 - 1750 Part of a Letter from Leonard Euler, Prof. Math. at Berlin, and F. R. S. to the Rev. Mr. Caspar Wetstein, Chaplain to His Royal Highness the ...