The image that can
be seen in the base of the viewer in the advertisement (below)
is, in fact, a reflection of the actual transparency. The transparency
is positioned in the upper sloping section.
The base of the viewer box holds a mirror, which is where the
image is viewed.
Tony Pritchard has supplied me with a copy of his
original instruction leaflet (left, below). Also, a copy of the
viewing instructions from The Dufaycolor book (see main Dufaycolor