Full Size Original
The Holerith tabulation system transferred information from the census schedules to paper punch cards using a pantograph. The punch cards measured 3.25 by 7.375 inches and contained 12 rows of 20 columns. (Cards used in later censuses had additional columns to collect more data.) Each position in a row and column corresponded to a specific data entry on the census schedule.
Census Bureau clerks using pantographs could prepare approximately 500 cards per day. To operate the mechanism, the operator positioned the punching stylus over the desired hole in a punch card template. Each hole in the template corresponded to a specific demographic category. Pressing the stylus into the template created a punched hole in the paper card that was read by the Hollerith tabulator's card reader.