It should always be remembered that the signature has nothing whatever to do with the size. It is merely a guide to the binder to show him how many leaves go to the quire, and the order in which they come. The binder found it convenient to have his quires of from eight to twelve leaves each, and the quires were thus made up whether the book was folio, quarto, or octavo. Let us assume, for example, that the quires were to consist of eight leaves each, then each quire of the folio book contained four sheets, of the quarto book two sheets, and of the octavo book one sheet. A book on Book Collecting, lately published, gives the following extraordinary remarks on finding the size:—“The leaves must be counted between signature and signature, and then if there are two leaves the book is a folio, if four a 4to, if eight an 8vo, if twelve a 12mo, etc.... I should advise the young collector to count the leaves between signature and signature, and to abide by the result, regardless of all the learned arguments of specialists.” The absolute folly of these remarks on the sizes of books will be apparent to any one who has seen an old book. The earliest folios printed in Germany and Italy are in quires of ten leaves, _i.e._ there are ten leaves between signature and signature; in the majority of early folios there are eight. Again, there is no folio book in existence among early books (excepting the block-books, which are in a class apart) with only two leaves to the signature. Wynkyn de Worde made up many of his quartos in quires of eight and four leaves alternately; most early 16mos were made up in quires of eight leaves, and had therefore two signatures to each complete sheet. In the same way many 24mos were made up in quires of twelve leaves. All these books would be wrongly described by counting the leaves between the signatures; in fact, that method comes right by accident only in the case of some octavos and a few 12mos and 16mos.[41] [41] On the subject of the sizes of old books, the reader would do well to consult the _Athenæum_, 1888, vol. ii, pp. 600, 636, 673, 706, and 744, where some instructive and amusing letters will be found. A further series of letters relating generally to the same subject appeared in the same paper in the early part of 1889.