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 them almost indispensable in any work where there is large quantity of complex data to be analyzed. It has been found feasible and profitable to use machines of this type in businesses of only moderate size.

Courtesy of the Tabulating Machine Company

Fig. 231. A Completely Equipped Office for Collecting and Tabulating the Operating and Sales Statistics of an Electric-Lighting Company

The girls at the left are operating the key punches for punching the cards. A gang punch is shown on the table at the extreme right. In the corner is the card-sorting machine, and the tabulating machine is in the center. Files for punched cards are seen along the wall

The adding machine is now so commonly used that it seems scarcely worth while to mention it here. There are, however, frequently times when special investigations must be made, but adding machines do not happen to be available, and the investigator feels seriously handicapped because he must take from the original records only those items which may be of especial interest to him. In work of this kind, it is sometimes convenient to use one of the small-size pocket adding machines of which there are several different makes now on the market. Though these machines are not at all in the same class as the large key-operated machines, they are of assistance in taking off occasional items because they overcome the necessity for putting