THE edges of the books being cut, the nest operation is to decorate their white surfaces in some manner. This may be done by colouring with sprinkle, self-colour, gilding or marbling. In this chapter we shall treat of the first two methods.
This the simplest and commonest kind of edge decoration, but very chaste and effective for some kinds of work when well done. The sprinkle is composed of some earthy pigment ground up with paste, and dissolved in water. Bole Armenian, or Armenian earth, a common red pigment, is generally employed. A quantity of this is piled, up upon a marble slab, and a depression made in the centre of it. Into this hole a little thin paste and a few drops of oil are put. The sides of the heap are then drawn over this, and the whole amalgamated together by a palette knife. When all is well mixed, the mass is drawn to the side of the slab, and a small piece, about the size of a walnut, brought with the knife to the centre of the slab, This portion is then carefully ground by the action of a marble or granite muller, such as is used by artists in grinding their colours. The action of the muller should be rotatory, and the pigment should often be gathered together with the palette knife, so as to ensure every portion being well and properly ground. When all the pigment has been thus reduced to the utmost fineness, it is placed in a large brown stoneware pot or other vessel, and sufficient clean water added to dissolve it all perfectly. The books to be sprinkled are next either placed in the laying-press, with their fore edges upward, and screwed up, or laid side by side on their backs on a board, and tightly corded round with a piece of string.
The operator now takes the "sprinkling-brush"-a large brush, the hairs of which are secured by a strong wrought iron rim (Fig. 86)Â soaks it well in the "sprinkle," and then presses out as much as he can against the side of the pot. Next, holding the brush by the handle in the right hand, and the short press-pin of the laying-press in his left, he strikes the former against the latter over the top of the pot until he has beaten most of the sprinkle out of the brush, and the spots which fall are very fine and regular. He carefully wipes the ring of the brush and the press-pin on a bunch of paper shavings. Then he goes to the row of books, and repeats the operation over their edges, holding the press-pin about two or three feet above them. Some dexterity and experience are required for the successful performance of this operation, as it is necessary that the spots should be very fine and regularly laid on. The higher the press-pin is held and the less sprinkle there is in the brush, the finer the spots will be. The whole of the edge should be carefully gone over, so as to keep the sprinkle very regular. The ring of the brush and the press-pin must be frequently wiped on the shavings, or the sprinkle will accumulate and be thrown down in great blots, destructive to the work. If necessary, the brush can be recharged and the surface again gone over. When the fore edges are finished, the heads and tails should be similarly treated, the backs of the books being from the operator. Care should be taken to give these edges the same amount of colour as the fore edges. It should be remembered that the sprinkle dries rather lighter. Occasionally school books and legal books have their edges sprinkled blue. Any good blue ink will answer the purpose. Other colours are rarely used, though sometimes foreign books are sprinkled in fancy colours; and such expedients as, say, colouring the edge over with yellow or pink, and then laying grains of rice or pieces of breadcrumb over the edge at intervals, and sprinkling it with blue, are resorted to. The rice or breadcrumb being then removed, the edge appears blue or purple, with yellow or pink interspaces.
The effects of this kind of thing, however, are hardly sufficiently good to be worth the trouble. Although the sprinkle-brush described and illustrated is that used almost everywhere, it may be well to mention that there still remain a few old-fashioned bookbinders who adhere to what is termed the "finger-brush." This is a brush about the size of a shaving-brush, of stiff hairs cut square at the ends. The brush, being dipped in the colour, is drawn across the fingers, so as to jerk the colour off in spots. The fingers should be slightly oiled. There is still another plan adopted by some. An ordinary nailbrush is dipped in the sprinkle. A common clean wire cinder-sifter is then held in the left hand above the row of books, and the brush, held in the right hand, is then worked round and round the sieve with the bristle next to the wires, when the spots will fall in a regular shower.
At the present time these are almost confined to red edges, which is the revival of a very old fashion. During the last century, however, other colours were in use, especially a lemon colour for whole calf books, which has been recently, in some degree, revived. Red edges are very suitable to devotional books, and have lately almost superseded gilt edges for prayer and hymn books. The pigment chosen is generally a vermilion of good quality, to which some binders choose to add more or less of carmine. The colour should be carefully ground with the muller upon a slab, some paste being mixed with it as for sprinkle. It is well to add a couple of drops of oil, and the same of vinegar and water. Some binders mix up the colour with paste and water only to the proper consistence; others prepare the colour with glaire. In colouring the edges equally over, the boards at the head of the volume must be beaten even with the edges, and the book rested on the edge of the press or table; then the back must be held with the left hand, and the colour applied with a small sponge, passed evenly over the edge, towards the back one way and the gutter the other, to avoid a mass of colour being lodged in the angle of the fore edge. This done, the other parts are similarly coloured, the fore edge being laid open from the boards, and a runner held firmly above to prevent the colour searching into the book. It will be perceived that a dozen volumes may be done as easily as one. For further security, and to prevent the colour searching into the books, it may be advisable to put them into the laying-press and screw them moderately tight.
Books of devotion were generally bound in black leather, and the edges blacked to correspond with the covers, so that it will be as well to describe the process : Put the book in the press as for gilding, and sponge it with black ink; then take ivory black, lampblack, or antimony, mixed well with a little paste, and rub it on the edge with the finger or ball of the hand till it is perfectly black and a good polish produced, when it must be cleared with a brush, burnished, and cased with paper. This kind of edge has, however, quite dropped out of favour, and is now rarely seen.
The following are the principal pigments used for colouring and sprinkling book edges: Blue-indigo and Prussian blue, with flake white or whiting for lighter shades ; yellow -Dutch pink, King's yellow, and yellow orpiment; brown - umber burnt over the fire; red-vermilion, or Oxford ochre, burnt in a pan; pink-rose pink (lake will make it brighter); green-the first and second mixed to any shade. But spirit colours are the best, because they will not rub in burnishing. These are generally made by mixing the colours in vinegar or mineral acid. Judson'a dyes make very good colours for the purpose.