1 Half-binding is that style of binding in which only the back and corners are covered with leather, and the sides with paper or cloth.
In the finishing or ornamenting of a bound book much taste may be displayed. The cut I edges of the leaves are usually either sprinkled ' with colour, smeared over uniformly with a sponge dipped in colour, marbled, or gilt with , leaf-gold; the edges being, for the last-men tioned process, previously coloured with red chalk and water, and then moistened with white of egg mixed with water, and subse quently burnished with a smooth bard stone, which polishes, but does not disturb the gold. The covers are sometimes coloured or sprin kled by the binder, and are impressed, both at the sides and back, with ornamental devices and inscriptions, by the application of heated stamps or dies, either with or without leaf gold; such impressed devices as are not gilt being distinguished by the name of blind.. tooling. When gold is used, the surface of the leather is prepared to receive it by the succes sive application of parchment-size, white of egg, and a little oil. In ordinary hand-work the patterns are produced by the separate sp .
plication of a number of small dies, and en graved rollers for lines and long narrow pat terns; but sometimes a number of dies are fitted together, and applied simultaneously by means of a press. This process is called blocking.
Much ingenuity and taste have been devoted of late years to the perfection of cloth-bind ing or boarding. By peculiarities in the mode of weaving the cotton cloth used for the purpose, and of subsequently stamping or embossing it between steel rollers, the textile appearance is destroyed, and a surface is sometimes produced very nearly resembling morocco loather.
The peculiarity of india-rnbber binding (which has been imitated with an artificial cement) consists in the entire absence of sewing. The back as well as the other edges are ploughed, so as to reduce the book to a collection of single leaves, to the back edges of which a layer of caoutehouc or cement is applied. This mode of binding is well adapted
for maps, music, ledgers, and manuscript books generally, as it allows the book to lie open with equal facility at any place, and the inner margin to be used, if needful, close to the edge of the paper.
Mr. Richards, a bookbinder, patented a few years ago a method of stitching the sheets by machinery ; but we are not aware that it has come much into practice.
The book-binding trade has gradually as sumed many of the features of the factory system. Some of the principal London firms, such as that of Messrs. Westley, have im mense buildings planned expressly for that species of combination and subdivision which mark the larger departments of manufactures. Tier after tier of stories, each lighted from end to end with numerous windows ; each story or range under the supervision of one foreman, and devoted to one department of binding ; separate warehouses for the mill board, the leather, and the cloth ; powerful machines for embossing cloth and stamping leather; a department where females are em ployed in folding, collating, and sewing ; ano ther department where men are engaged in glueing, pasting, cutting, hammering, and pressing the 'boarded' books ; another de partment for the 'roan' or ' sheep ' binding ; a fourth entirely devoted to those school books which (whatever be their merit), have a sale so enormous and continuous that the process of binding them is always going on ; a fifth occupied by the ' extra' workmen em ployed in the costlier kinds of binding—such are the features of the establishments in question : establishments where many hundreds of workpeople are employed undek one roof.
We may reasonably hope that our book binders; as well as those of foreign countries, will not be slow to contribute to the grand In dustrial Congress of 1851. It is profitable, too, to glance once now and then at the curious specimens of bookbinding belonging to the nth, I6th, and 17th centuries : many beauti ful examples of such work were placed in the Exhibition of 1850.