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 is clipped off. If any card in the stack is arranged improperly, it will show because the card will project beyond the other cards at the clipped corner of the pile. The stacks of cards are run through a sorting machine such as is seen in Fig. 229. Needles connected to electric wires make a contact through the holes in the card, and operate the sorting mechanism automatically in such manner that the cards are dropped into compartments in accordance with the position of the punched hole on the card. Cards are sorted for one particular characteristic at a time, so that all cards having that characteristic are obtained for tabulating purposes. After the data on one set of cards have been tabulated, the cards can then be run through the sorting machine again and sorted for other characteristics. This permits using the punched cards over and over again until all of the different data which may be of interest have been taken from the cards by the tabulating machines.

Courtesy of the Tabulating Machine Company

Fig. 229. Hollerith Card-Sorting Machine Suitable for Use by Corporations for Statistical Work Relating to Sales, Costs, Etc.

This machine will sort about 12,000 cards per hour, and place in the right compartment all cards having the hole punched in the same position in the particular column for which the sorting is done

Fig. 230 shows the tabulating machine as used in the general commercial work of corporations, and for State or municipal departments. The cards are placed in the machine at the left and are fed through automatically, one by one, so that electric contacts are made wherever there are holes punched in the card. The electric contacts cause the counting dials to revolve by just the right amount to record properly the data for each punched hole.