When the ground color has spread out to the desired dimension, throw on the black a drop of blue, then yellow on the blue and red on the yellow which must all expand to a diameter of 1-1/2 inches. Should this not be the case then several drops of gall are to be added in the order aforesaid. The three latter colors must be prepared by themselves, and if, after throwing a drop of blue on the black, the former does not reach the necessary expansion, gall must be added in drops until this is achieved, then the yellow is manipulated in the same way. When all colors are toned in regard to their power of expansion, then and not before then, can the marbling commence. With a little experience or practice the whole manipulation is finished in less time than it takes to describe it. Pour the size into the trough, take the top of it off with a thin piece of wood which fits into the trough closely, smooth it over with the wood so that the surface is free of bubbles, then throw on, by the aid of a hair brush, the black in the direction of the length of the trough towards the centre of the size in such a way that the first drop comes in contact with the rim of the second, the second with that of the third, the third with the fourth, etc., so that a ribbon from 4 to 5 inches wide is formed. Then throw on the blue in drops at both sides of the black following the length of the trough, but the joining of the drops must be avoided. Yellow is thrown on at both rims of the black just as the blue was but in such a way that each drop of blue has a yellow centre. Finally red is thrown on the yellow so that each drop of yellow receives a red centre. By this means we produce a beautiful combination of colors. Then take a thick knitting needle or a thin stylus of wood and draw the colors in wavy lines through each other but so that the stylus will pass the boundary of the black. By doing this white lines will be produced between the colors, adding at the same time, the fifth color white which causes the marble to attain a brighter aspect. If then the comb is drawn across, beautiful scales will be produced. The books which have been wetted shortly before with alum water, are now placed between boards or clamps and are dipped from right to left, somewhat obliquely, into the trough so that the left end of the book touches the size first, and then with a firm hand the book is inserted towards the right until the right end has touched the size. This must be quickly done to avoid the formation of air bubbles. As soon as the marble edge is taken off, the superfluous size is carefully removed from the edge by a moist, soft sponge so as to prohibit moisture from penetrating too much into the leaves of the book. In this operation great care must be exercised to prevent the marble edge being rubbed out or spoiled.