Barnard & Gowenlock's Kromaz Stereoscope

Mahogany sliding frame with three filters (red and blue side-by-side and green below), and a ground glass focusing screen. The Kromaz system patented in England in the late 1890s was a rival to Ives's Kromskop. The system of filters was arranged in such a way that the stereoscopic colour-separation transparencies were laid on a viewer similar in appearance to the Kromskop viewer but in a single step with label: BARNARD & GOWENLOCK'S KROMAZ REGISTERED, very rare, only a few are known to exist, in very good original condition