A signature is a term attributed to a number or letter located at the bottom of the first page of every section of a book.
Signatures were used before pagination was established; however their role was not of use to the readers of the book, but to the workers who folded the sheets of paper, creating different sections, or gatherings, of the book. As Gaskell (1972) explains, books were not printed leaf by leaf, but on large sheets of paper. These sheets of paper were then folded to create groups of leaves, which were then cut accordingly. It was essential that they were assembled in the correct order and the right way up, so to assist the people doing so, a signature was placed at the foot of the first page of each sheet, and sometimes on subsequent pages too.
The signature was more often than not a letter of the Latin alphabet. The use of Arabic figures was toyed with for a brief time, but did not garner much success. The Latin alphabet contained twenty-three letters, A to Z, excluding the letters I or J, U or V, and W. This alphabet was traditionally used well into the nineteenth century.
If the book in question had more than twenty-three gatherings, (i.e. more than twenty-three sheets of paper were used in its production), the twenty-fourth gathering usually began with the signature Aa and continued on in this sequence until it reached Zz. Again, if there were over forty-seven gatherings to the book, the sequence usually began again with Aaa. Gaskell outlines that in the eighteenth century, English printers preferred to use 3A for Aaa, 4A for Aaaa and so on. In the sixteenth century, signatures were widely printed in lower-case.
It is worth noting that the form of signatures varied from place to place as well as from different time periods. Until the end of the sixteenth century, English printers used Roman numerals for suffixes, but this later became synonymous with French printers.
The main signature series in an English book normally began on the first recto page of the text of a book, usually bearing the signature B. This was to allow for the preliminaries, or the first pages bearing the title, dedications, preface, etc., to be added afterwards, on which the signature A was usually printed. The second recto usually bore the signature B2, the third B3, the fourth B4. In my 1799 copy of Sacred Dramas: Chiefly Intended for Young Persons, by Hannah More, the sequence stops after B4, but begins again, four rectos later, with C. The fact that there are eight leaves in each gathering tells me that my book is collated in an octavo format, just as a book with two leaves in each gathering is known as a folio, and one with two leaves in each gathering, a quarto.
Gaskell, P. A New Introduction to Bibliography. Ocford: Oxford University Press, 1995.
Contributed by Aisling Owens.