This negative taken by William Henry Fox Talbot (1800-1877) is the earliest camera negative in existence. Lacock Abbey in Wiltshire, which now has a photography museum, was the Talbot family home. By the side of it Talbot has written 'Latticed window (with the Camera Obscura) August 1835. When first made, the squares of glas about 200 in number could be counted, with help of a lens'. Fox Talbot invented the first negative/positive proces - any number of prints could be made from the same shot by transferring the negative image on to special paper to make a positive print; these were called calotypes.
© National Museum of Science & Media / Science & Society Picture Library