Note 23 to Chapter 5 of the author's Pegasus in Harness: Victorian Publishing and W. M. Thackeray, which University Press of Virginia published in 1992. It has been included in the Victorian Web with the kind permission of the author, who of course retains copyright.
The terms sheet, signature, and gathering all refer to the same basic unit of the book produced at the printing press. In Vanity Fair, first edition, each gathering consists of sixteen pages (eight leaves) and is signed at the foot of the first and third pages.
Last modified: 4 April 2001