"You know I've been thinking," Hamilton said thoughtfully, "that while I suppose it is all right getting all those holes punched in a card, and so forth, I should think it would be fearfully hard to handle the card afterwards. All these little holes look so much alike."
"To the eye, perhaps," the chief said, "but you must remember that these cards are never sorted by eyesight. And you must remember that the sorting process is done by machinery all the way along, just as the verifying and the tabulating is handled in a purely mechanical fashion. You remember that each card was punched with a gang-punch?"
"Of course," the boy said, "that was to specify the district."
"We keep all those together from the time they are punched till after we are through with the verifying, so that all the cards of a certain enumeration district, and of every section in that district, are kept together in a separate box."
"My word," Hamilton exclaimed, "what a storage you must have!"
"You ought to go down and see it some time," the other said. "It's big enough, with every State and every county and every district in the country having its own place, and every little village in that district right where it belongs in a box of its own, under that State, county, and district. I'm telling you this just to show you that we don't have to sort the cards for location at all, and that in itself saves us a lot of labor and time."
"And they were sorted into sexes on the punching machine, I remember," Hamilton remarked.
"Yes, and that prevents another handling of every card, you see," the chief went on, "so that without any further special division, every card is divided by village, district, county, and State, as well as sex, when it leaves the punching machine From there it comes to the tabulating machine—which is just the same as the verification, only instead of the electrical connections being made through relays only, they are sometimes made direct to counters."
"Just how, Mr. Cullern?" the boy asked.
"Well," the other continued, "when the pin, passing through the hole in the card, drops into the little cup of mercury it closes a current passing through an electro-magnet controlling a counter or a dial corresponding with each possible item of information on the card, and for each contact made to each dial, an added unit is registered. The tabulating process is completed by an automatic recording and printing system, somewhat along the stock ticker plan, connected with each dial. When desired, touching an electric button will cause every dial to print automatically the number recorded on a ribbon of paper."