15th October

On this day in 1698, King William III commissioned Edmund Halley as Royal Naval Captain of the HMS Paramour and provided him with a complete set of instructions:
Whereas his Majesty has been pleased to lend his pink the 'Paramour' for your proceeding with her on an Expedition, to improve the knowledge of the Longitude and variations of the Compass, which ship is now completely manned, stored and victualled at his Majesty's charge for the said Expedition ...
See a picture at THIS LINK.

The postage stamp of one of today's mathematicians at THIS LINK was issued in 1958.