The tabulator can select and list information from cards. Also, it can total information from groups of cards in _counters_ of the tabulator and can print the totals. [Illustration: FIG. 12. Tabulator.] The tabulator (Fig. 12) has one card channel with two stations where cards may be read, called the _Upper Brushes_ and _Lower Brushes_. When the Lower Brush station is reading one card, the Upper Brush station is reading the next card. The tabulator also has another channel, which is for endless paper (and sometimes separate sheets or cards). This channel has one station; here printing takes place. Unlike the typewriter, the tabulator prints a whole row at a time. It can print up to 88 numerals or letters across the sheet in one stroke. The cards flowing through the card channel and the paper flowing through the paper channel do not have to move in step; in fact, we need many different time relations between them, and the number of rows printed on the paper may have almost any relation to the number of punch cards flowing through the card channel. At the station where paper is printed, we can put on the machine a mechanism called the _automatic carriage_. This is like a typewriter carriage, which holds the paper for a typewriter, but we can control the movement of paper through the automatic carriage by plugboard wiring, switch settings, and holes in punch cards. Thus we can arrange for headings, spacing, and feeding of new sheets to be controlled by the information and the instructions, with a great deal of versatility. HANDLING INFORMATION We have now described briefly the chief available punch-card machines as of the middle of 1948. The next question is: How do we actually get something done by means of punch cards? Let us go back to the census example, even though it may not be a very typical example, and see what would be done if we wished to compile a census by punch cards. The first thing we do is plan which columns of the punch card will contain what information about the people being counted. For example, the following might be part of the plan: NO. OF INFORMATION POSSIBILITIES COLUMNS State 60 1- 2 County 1,000 3- 5 Township 10,000 6- 9 City or village 10,000 10-13 Sex 2 14 Age last birthday 100 15-16 Occupation 100,000 17-21 ... ... ...