The sprinkled colors are first tested with strips of paper; cuttings of clean note-paper are saved for this purpose. The edges of a book can be marbled only when the book is level or straight, therefore they must be marbled either before rounding or the book already rounded must be leveled by knocking it on a stone or meta] slab. In all cases the marbling is done both with papers and books by dipping from one corner to the other diagonally opposite but never deeper than just sufficient to take off the layer of color. To prevent the color from getting between the leaves the edges are held between zinc plates, which must be dried each time after using. To make the paper or edges take the colors more readily and to prevent any subsequent running off, the edges are lightly washed down with alum water. This wash is made by boiling 100 g. of alum in 1/2-litre of water and using it solely for this work.

The alum solution is laid on with a sponge, with which the edges are washed over. The moisture must have thoroughly soaked in therefore it is necessary to do it 10 minutes before marbling.

If, however, the edges have become thoroughly dry they will take the colors badly. This occurs in from 20 to 30 minutes, according to the temperature. Marbling can only be done in a warm room where the temperature is equable and where there is no dust.

The marbling bath must be of the same temperature as the room. The body must be skimmed each time before sprinkling the colors, but the colors must be sprinkled on immediately afterwards.

An excellent treatise on the work of marbling edges has appeared under the title: *Fortschritte del Marmorirlcunst. Von Joseph Halfer. William Leo, Stuttgart.

Gilding edges takes up most time when only occasional books are to be done. The fore-edge can be treated either flat or round. In every case the book must be placed in the press within boards. These boards are narrow strips, about 1/2-cm. thick and up to 5 cm. in width; they must be of equal thickness and beveled only on long side, the edge itself must be rounded.

Many makers send out boards beveled right from one side to the other. This kind is very unsuitable and has many disadvantages. The boards must not be made from wood of very open grain, and firs and oaks must not be used. The boards are to be somewhat longer than the edge about to be treated, so that the edge may be as firm and tight as possible and at the same time easy to work upon; two outer boards are added to those regularly used, as shown in Figs. 49 and 50.

The inner boards are quite flush with the book: the latter must on no account stand back. The outer boards are about 3 mm. behind the others; the book is so placed in the press, and here again the book and boards must be exactly level with the press cheeks. The press is then screwed up as tight as possible. If the inner boards have not perfectly straight edges they must be planed down.

The edges are to be scraped down quite smooth with a scraper or, if necessary with a knife; the scraper must not be sharpened for this purpose as the carpenter sharpens his tools, that is, not to a cutting edge but as though it were for carving, until a bevel (or turned edge) of about 3 mm. has been ground. The edge thus gets a turned edge, with which the book is scraped. If it should cease to "take," the old edge is rubbed down with steel and a new one made by a few firm strong rubbings. The edge should be wetted a little to prevent its heating. Flat edges are scraped with a flat scraper, rounded edges with one suitably rounded. In this case the round of the blade must be more decided than that of the edges, as it would otherwise be impossible to get into all parts of the edges. Scraping with pieces of glass is an antiquated, clumsy method.

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