J. Reygondaud, Paris, Stereo Field Camera
By the latter part of the 19th century a thriving business had evolved for both professional and high quality amateur cameras. The sliding box style had given way to tailboard cameras with leather bellows, and then folding cameras with a fixed plate holder and moving front element such as this (circa 1890) Reygondaud. It has both mono and stereo lens sets mounted on roller blind shutters. The stereo lens pair are Darlots. The mono shutter is by Mattioli. The stereo shutter has a trademark, but I don't know if its Mattioli or someone else. The single lens is a Goerz of most likely later vintage. The accessory view finder is an interesting piece. With the top cover closed, it works as an eye level finder. Open the cover and a mirror drops down internally, making it a waist level finder.
In this photo one can see the hardened reamins of a pneumatic shutter release bulb.