Page:The Art of Bookbinding, Zaehnsdorf, 1890.djvu/58

28 of wood loaded at one end with lead, or a thick folding-stick may be used as a substitute. I must again call particular attention to the kettle stitch. The thread must not be drawn too tight in making the chain, or the thread will break in backing; but still a proper tension must be kept or the sheets will wear loose. The last sheet should be fastened with a double knot round the kettle stitch two or three sections down, and that section must be sewn all along. The next style of sewing, and most generally used throughout the trade, is the ordinary method. Ordinary Sewing is somewhat different, inasmuch as the thread is not twisted round the cord, as in flexible work, when the cord is outside the section. In this method the cord fits into the saw cuts. The thread is simply passed over the cord, not round it, otherwise the principle of sewing is the same, that is, the thread is passed right along the section, out of the holes made, and into them again; the kettle stitch being made in the same way. This style of work has one advantage over flexible work, because the back of the book can be better gilt. In flexible work, the leather is attached with paste to the back, and is flexed, and bent, each time the book is opened, and there is great risk of the gold splitting away or being detached from the leather in wear. Books sewn in the ordinary method are made with a hollow or loose back, and when the book is opened, the crease in the back is independent of the leather covering; the lining of the back only is creased, and the leather keeps its perfect form, by reason of the lining giving it a spring outwards. Morocco is generally used for flexible work; calf, being without a grain, is not suitable, as it would show all the creases in the back made by the opening. This class of sewing is excellent for books that do not require so much strength, such as library bindings, but for a dictionary or the like, where constant