Les Diableres, a series of more than 70 stereoscopic photographs published in Paris in the 1860’s. Featuring the work of several different sculptors, the images of intricate clay dioramas depicted scenes from Hell. Meant to me viewed through a stereoscope for a 3D effect, many were hand colored and in some cases the eyes of the skeletons and demons were replaced with gel and backlit so that they would glow red.

Edited to add :: Here’s a link to the book, available on Amazon!