This is a glass Balopticon slide known as a “Balop-card” used in the Balopticon manufactured by Bauch & Lomb Optical Co., New York. The Rex Theater use the Balopticon to advertise “The Mark of Zorro;” a 1940 American black-and-white swashbuckling adventure film from 20th Century Fox, produced by Darryl F. Zanuck, directed by Rouben Mamoulian, that stared Tyrone Power, Linda Darnell, and Basil Rathbone.
The Balopticon and several slides were donated to the Museum by the Boundary County School District #101.
Zorro Balopticon