PHOTOCHROM GUIDE TO : Switzerland & the Alps, 1890-1905.
These Photochrome images of Switzerland are by Photocrome Zurich, made shortly after they invented the process in the 1880s.
There were 3 variations of the Photocrome processes at the time; Fotochrom, & Aäc Photocrome & the original, PhotoChrome.
The Photocrome process was an old school process for colourizing black-and-white negatives via the direct photographic transfer of a negative onto lo-fi lithographic printing plates made of stobe. The process is a photographic variant of chromolithography (color lithography).
Creatively choosing colour & then using a mechanical process to apply that colour to a black & white photo rather than doing it by hand. Colouring-in a monotone world.