This is one of the simplest while-U-wait cameras for direct positive prints on cards. A pack of cards is loaded though a light-tight sleeve, these fit into a metal box behind the image plane. After an exposure the box is hinged down, the front card is picked up and dropped into the combined developing and fixing solution contained in a tank below the camera. Recommended exposure was from 1/2 to 3 seconds, development took about a minute, the card was then rinsed. The developing tank slides backwards to enable the card to be removed a plate attached to the tank blocks the aperture into the camera. Chicago Ferrotype had a UK office at 12 St John's Lane Liverpool.