I must mention here a newly discovered medium which has been found essential in the formation of beautiful veins in plain marble; take 1/10 quart of shellac orange, add 1/8 quart spirits of ammonia, allow the whole to boil for 5 minutes stirring repeatedly (by which a uniform solution of shellac in ammonia is obtained), take it from the fire and dilute the solution with about 2 quarts of water. Throw the fluid by means of the brush on the size and then throw on the body-color, _see plain gray marble_. In this way beautiful white veins will appear, which is explained by the fact, that the surface of the size is covered with an expanding medium, which can be forced together by the body-color, but is strong enough to hinder the union of the latter. MARBLING OF GILT EDGES. MARBLING OF GILT EDGES. If gilt, silver or aluminium edges are to be marbled, burnish slightly and moisten by a soft brush with a solution of powdered alum in hot water which is of the consistency of a thin pap. The marbling of the gilt-edge is then executed in the usual way before the coating of alum is entirely dry. After the marbling is done, water is poured over the edge until it is entirely clean. When the edge is completely dried it is rubbed over with a waxed rag and is then burnished in the usual way. For marbling the usual marbling colors are applicable, but it should here be added, that very dry edges will not take the marbling colors readily. MARBLING ON A LARGE SCALE. For the purpose of marbling on a large scale especial arrangements have to be made, and it is wonderful how elegant and practical are the marbling rooms of large establishments. For instance the tables and floors are of stone and cement, or of wood covered with zinc plates, and the troughs and receptacles to take off the fluids which have been employed are to be found in universal use. Even large iron cranes are erected to hold the books together and lift them off, and to transport them to the revolving drying apparatus, which can be heated. These arrangements are in keeping with the extent of the business and can here only be lightly passed upon. THE UTENSILS. THE UTENSILS. THE MARBLING TROUGH. The marbling trough is a long flat oblong box of about 20 inches in length, 10 inches wide, and 1-1/4 inches deep inside, and should be painted within with white oil-paint so that the size appears light making the colors more readily discernible. This trough must have inserted on one side a sloping partition of sheet zinc so that the waste of color may be skimmed over it by aid of paper slips or a piece of wooden board without running it over the top. In addition to the trough containing the marbling size, a second smaller trough or basin of 10 inches width, and 1-1/4 inches depth is necessary for the reception of the waste of color. This is to be placed, while marbling, immediately to the left of the first trough. SIZE SKIMMER.