[3] This is not to be confounded with public library bindings.
Intelligence must, however, be used; a book that has already been cased (or bound and sewn on cords) must of necessity have the saw cuts or holes, and such a book would show the cuts.
There is another mode called “_flexible not to show_.” The book is marked up in the usual way as for flexible, and is also slightly scratched on the band marks with the saw; but not deep enough to go through the sections. A thin cord is then taken doubled for each band, and the book is sewn the ordinary flexible way; the cord is knocked into the back in forwarding, and the leather may be stuck on a hollow back with bands, or it may be fastened to the back itself without bands.[4]
However simple it may appear in description to sew a book, it requires great judgment to keep down the swelling of the book to the proper amount necessary to form a good backing groove and no more. In order to do this, the sheets must from time to time be gently tapped down with a piece of wood or a heavy folding-stick, and great care must be observed to avoid drawing the fastening of the kettle stitch too tight, or the head and tail of the book will be thinner than the middle; this fault once committed has no remedy.
If the sections are very thin, or in half sheets, they may, if the book is very thick, be sewn “_two sheets on_.” The needle is passed from the kettle stitch to the first band of |30| the first sheet and out, then another sheet is placed on the top, and the needle inserted at the first band and brought out at band No. 2, the needle is again inserted in the first sheet and in at the second band and out at No. 3, thus treating the two sections as one; in this way it is obvious that only half as much thread will be in the back. With regard to books that have had the heads cut, it will be necessary to open each sheet carefully up to the back before it is placed on the press, otherwise the centre may not be caught, and two or more leaves will be detached after the book is bound.
The first and last sections of every book should be overcast for strength. With regard to books that are composed of single leaves, they are treated of in Chapter III. They are to be overcast, and each section treated as a section of an ordinary book, the only difference being, that a strong lining of paper should be given to the back before covering, so that it cannot “throw up.”