During the 1880s the engineer Herman Hollerith devised a set of machines for compiling data from the U.S. Census. Hollerith's tabulating system included a punch for entering data about each person onto a blank card, a tabulator for reading the cards and summing up information, and a sorting box for sorting the cards for further analysis.
This third part of the system, the sorter, is shown on the right in the photograph. It is an oak box with 26 vertical compartments arranged in two rows. Each compartment has a brass cover that is held in place by an electric catch connected to the tabulator. The sorter is connected by a cable to the tabulator. Once a card is read by the tabulator, a compartment opens in the sorter, indicating where the card should be placed for further counting. The front and back sides of the sorter open so that one may remove stacks of cards from the compartments.