The title, preface, &c. of a volume are commonly left till the body of
the work is finished, as circumstances may arise in the course of its
progress through the press which will induce the author to alter his
original preface, date, &c., or the work may conclude in such a manner
as to admit of their being brought in at the end, in order to fill out
a sheet, and thus save both paper and press-work. For this reason, it
is well to begin the first sheet of every work with signature B (or 2),
leaving A (or 1) for the title-sheet.
It was formerly the custom to omit the letters J, V, and W in the list of
signatures. But the greater convenience attending the use of twenty-five
letters has recently induced several of our largest establishments to
omit the letter J only.