Heliograph of the Day

A big day for birthdays today - my Derbyshire cousin for one. But it's also the birth date (in 1765) of the great French inventor Nicephore Niepce, who in 1825 created what is accepted as the oldest surviving photograph. It's not much to look at - an almost abstract view of a roof and some angles of a building  - so I've put a more decorative later still life above this post, one that neatly compendiates the French preoccupation with the table. Niepce called his photographic technique 'heliographie' - 'sun drawing' (it involved a mixture of bitumen and lavender oil). Years before this, in 1807, Niepce had also built the first working internal combustion engine, which was used to power a boat on the river Saone. The combustive mixture included clubmoss spores, and Niepce called his engine a 'pyreolophore' - 'bearer of fire and wind'. How poetical the language of science and technology once was...
Today is also the birthday (in 1792) of the mathematician, astronomer and much else, Sir John Herschel (below) - who, happily, was in his old age the subject of some extraordinarily expressive portrait photographs by Julia Margaret Cameron.
And it's the 139th birthday of Maurice Ravel - which Radio 3 is marking by devoting the entire day to his works. Bravo! say I.