Presuming that the paste or ground-wash is thoroughly dry, take liquid salts of tartar and dilute with cold water, 1 part salts to 2 of water, in a basin; wash the calf with this liquid evenly, using a soft sponge. The calf will require the wash to be applied 2 or 3 times, until a proper and uniform tint is obtained. Each successive wash must be allowed to get thoroughly dry before the next is applied.
The next process is to sprinkle the book, with the boards open; 2 pieces of flat wood, about 3 ft. long, 4 in. wide, and £ in. thick, will be found very use ful for carrying the book. These rods must be supported at each end, so that the book may be suspended between them, with the boards resting on the rods nearly horizontally. Put into a round pan some of the copperas fluid, and into another some of the solution of oxalic acid. Use a pretty large brush for each pan, keeping each for its own fluid. The sprinkling may be commenced. The brushes being soaked in the fluids, should be beaten out, using a broomstick to beat on before beating over the book, unless a coarse sprinkle is desired. Whilst beating over the book, the hand should be held up high, and moved about, so that a fine and equal spray may be distributed; and this should be continued until the desired depth of colour is attained.
This may be varied by putting some geometrical design, cut out of thin mill-board, on the cover; or if the book is on any special subject, the subject itself put on the cover will have a very pretty effect, and may be made emblematical. A fern or other leaf for botanical work as an instance. The sprinkle must in these cases be very fine and dark for the better effect. The leaf or design, being lifted from the cover when the sprinkle is dry, will leave the ground dark sprinkle with a light brown leaf or design. "Cambridge calf" is done in this way by cutting a square panel of millboard out and laying it on the sides. The square on the cover may be left brown or may be dabbed with a sponge.