This is a punch used for preparing punch cards for the United States Census of Occupations of 1920. It has a triangular open metal base that holds a plate at the front on which a celluloid plate marked like one of the punch cards used in this census, with appropriate holes, rests. Behind this is a support for a card to be punched. Reaching across the instrument from back to front is a long metal rod which has a punch toward the center and a point at the front that fits into the holes in the celluloid plate.
A mark on the plate reads: OCCUPATION 1920.
A punch similar to this one was used in the U.S. census of population of 1890, the first carried out with tabulating equipment. Other forms of card punch were introduced in 1910, but proved less satisfactory. The year 1920 was the last in which a pantograph punch was used in the U.S. Bureau of the Census.
Compare MA.312896.
Reference:
Leon E. Truesdell,The Development of Punch Card Tabulation in the Bureau of the Census 1890-1940, Washington: U.S. Department of Commerce, 1965, pp. 140–46, 160.