Note 1 — Chapter IX
Reading edition
A quarto volume, or quarto, is a book which is the size of a fourth of a sheet of printing paper. The sheets are folded twice to make four leaves or eight pages, and the usual size is about 6x9 in. A folio is a volume of the size of a half sheet of printing paper. The paper is folded once and bound in the middle, the usual size being about 9 x 12 in. The divisions of the book made by thus folding sheets of paper are called quires, and may consist of four or eight leaves.