must, in all cases, be guided in the depth by the thickness of the cord to be used. The size of the book should determine the thickness of the cord, as the larger the book, the stronger and thicker must be the cord. Suitable cord is to be purchased at all the bookbinder's material shops, and it is known by the size of the book, such as 12mo., 8vo., 4to. cord.
I think nothing looks worse than a book with great holes in the back, sometimes to be seen when the book is opened, which are due to the inattention of the workmen. Besides, it causes great inconvenience to the forwarder if the cords are loose, and the only thing he can do in such a case is to cram a lot of glue into the grooves to keep the cord in its place. If, on the other hand, the saw cuts are