Q. I am a small press. I would like to know what the numbers on the copyright page represent that are written: 2 3 4 5 6 10 9 8 7 6 5 4 3, for example.
A. This is the impression line. In Chicago’s books, the numbers are arranged somewhat differently from your example. A book printed this year would have the following numbers:
14 13 12 11 10 09 08 07 06 05 1 2 3 4 5
The first group of numbers refers to years (2014 to 2005), and the second group indicates the impression number. The line tells the reader that this is the first impression, printed in 2005. If the next impression were printed in 2007, the printers would mask the numbers 05 and 06 in the first group and the number 1 in the second group, so the following line would appear:
14 13 12 11 10 09 08 07 2 3 4 5
This would tell readers that it was the book’s second impression, printed in 2007, and it could be done without retypesetting the copyright page.