"It's not supposed to punch until the whole card is ready," the other explained. "You depress into position the various keys you want until all the records needed for this one card are ready. Then you can glance over your keyboard, comparing what might be called your map of depressed keys with the line of the schedule you are copying. If one is wrong, you can release that one and put down the correct one in its place, the card being as yet untouched. You see, each field or division of the card corresponds with a differently colored section of the keyboard, and this makes it easy to insure accuracy in reading from the schedule." "But how is the punching done, then?" queried Hamilton. "You press the bar," the foreman explained, "and that throws in the motor attached to the punching mechanism, which brings the entire die and card up against the end of the punches which have been depressed by the operator, including, of course, the gang-punch, and these perforate the card. It is then immediately withdrawn, and drops automatically into either the 'male' or the 'female' compartments of the machine, the location of the hole tilting the slide that determines on which side the punched card shall fall." "So that really the sorting into sexes is done by the one and the same operation as the punching of the card," the boy remarked; "I see now. That's a first-class idea." "It saves a great deal of work," the older man said. "Then, too, with the same group of motions a new card has been fed from the holder and is in place for punching. At the same time, the schedule, which is held in rigid alignment, has been turned just exactly the right amount to bring the next line in the direct vision of the operator. Thus he never has to stop and think whether he has done a line or not and never skips a line because of an error of eyesight." "I can understand that now," the boy answered "Now let me see whether I really can do the rest of the card. In what you call the third column--though it is really the fifth--I punch either 'Hd' for the Head of the Family, 'Wf' for Wife, 'S' or 'D' for Son or Daughter, and 'Ot' for Other?" "That's right." "Then, further down the same line, 'M' is Male and 'F' is Female. That's easy enough. In the next section down, but still in the same line is 'W' for White, 'Mu' for Mulatto, 'B' for Black, 'Ch' for Chinese, 'Jp' for Japanese, and 'In' for Indian." "Go ahead," the foreman said, "you're not likely to go wrong as yet." "The age seems clear, too," said Hamilton, "you punch the five-year period nearest to the age and then add on. For instance, the way it looks to me is that if a fellow was sixteen, you would first punch the '15' and then the '1' in that little cornerwise bit at the bottom of the next section. But I don't see what the '5' is for." [Illustration: FACSIMILE OF PUNCHED CENSUS CARD. Example of record made for every person in the United States, this card being the actual record of the author.]