Until very recently I never realized that there was color photograph
y before the invention of color film. Around 1906 at least two men, Dr. Adolf Miethe
and Sergei Mikhailovich Prokudin-Gorskii
invented cameras capable of taking color photographs. (Prokudin-Gorskii
apparently also held a patent
on a method of showing color moving pictures, but I haven't found any existing examples of this.)
The camera worked the same way other black & white cameras of the day worked: it used glass plate negatives to capture the image. The difference here was that the camera used three glass negatives for each photo, each one filtered for either red, green or blue. This produced a black and white negative, but one which had only captured certain wavelengths of light, instead of the full spectrum.
The negatives couldn't be printed in color, however. In order to be viewed in color one had to use a special projector, also designed by Prokudin-Gorskii, in which the three slides were projected on top of each other onto a screen, each with their respective color filters in place.
Recently color composites have been created from the old glass negatives and the result is astounding. I'm one of those people who thinks that everything before 1950 happened in black and white, so crisp, full-colour photos of the pre-Revolution Russian Empire really made my head spin. You can find an online version of a Library of Congress exhibit featuring these photos at http://www.loc.gov/exhibits/empire