BOOKBINDING. The process of binding books, or putting the sheets together into the form of books. The bookbinder receives the sheets which compose a book immediately from the printer, and after having folded them id the order of the signatures, or letters at the bottom of the page, they are first beaten with a hammer on a stone, to make them lie close and smooth ; after which they are put into a press, and sewed with bands, or strips of leather fastened at certain distances, which, being all glued together very firmly, form the back of the book, to which the pasteboards are attached by means of the bands, so as to form the sides. In all this process of fixing on the sides, much art and nicety is required in rounding the back, and keeping the whole firmly fixed in the press. After this the book is put into the cutting-press between two boards, one lying even with the press for the knife to run upon, the other above for the knife to run against In this manner the leaves and boards are cut to form an even edge. The next operation is the sprinkling of the leaves, which is done by means of a brush dipped in vermilion and sap green. The covers of leather, die. being first moisten ed, are cut to the size of the book, smeared with paste, and then stretched successively over the back and the two sides, after having taken off the four angles, and indented and platted the cover at the head band. When
thus far finished, the book is covered and bound between two bands and set to dry. It is afterwards washed with paste and water, and then sprinkled with a brush, unless it is to be marbled, which is done by making spots with vitriol. The book is then glazed with the white of an agg, and, lastly, polished with a hot iron. The letters and ornaments are made with gilding tools, or brass cylinders, rolled along by a handle : to apply the gold, the leather is glazed with a liquor made of the white of eggs, diluted with water, and when nearly dry the gold is laid on. Such is the process when a book is fully bound ; but books may sometimes be only sewed and have a paper cover, when they are said to be sewed ; sometimes the boards are covered with paper only, when they are said to be in boards; and sometimes they have a leather covering on the back, extending a small way over each aide, when they are said to be half bound.