The Subway in the 1920's
Machines for automatically changing dimes, quarters and half dollars were installed for trial in the northbound Seventy-seventh Street station of the Lexington Avenue subway, operated by the Interborough Rapid Transit Company, New York. The machine was developed by Frank Hedley, president and general manager, and J. S. Doyle, assistant general manager. The installation consisted of two units, which were installed in the panels of the change-making booth at the Seventy-seventh Street station. The machines were approximately 30 square in., and the coin to be changed was inserted through slots at the top. A sign over the machine read "Automatic Money Changing Machine -- Insert Money Here" and arrows pointed to the slots for the reception of the coins. When a coin was inserted, it dropped upon two contact points in the change-making machine and established an electric circuit to release the necessary change. The coin was held in position back of a magnifying lens, so that it could readily be seen by the person who inserted the coin. Similar lenses on the back of the machine inside the booth also provided for an operator's inspection. A switch was provided in the operator's booth so that he could open the circuit and thus automatically prevent the issuing of change, should it be necessary to retain a coin for inspection. Inserting a second coin in the slot released the one in view and the second coin took its position upon the inspection contact.