Blacking, in general, signifies a factitious black ; as lamp-black, shoe-black, etc. The common oil-blacking consists of ivory-black mixed with lintseed-oil.— The shining blacking is made in various ways, and affords employment to several persons in the me tropolis, who prepare it for the supply of the shops. The preparation which has experienced the most extensive sale is probably that of Mr. Bayley. His patent being expired, we shall communicate the particulars of the process. Take one part of the gummy juice that issues, in the months of June, July, and August, from the shrub called the goat's thorn ; four parts of river-water ; two parts of neat's foot, or some other softening, lubricating oil; two parts of superfine ivory-black} two parts of deep blur, prepared from iron and copper; and four parts of brown sugar-candy. Let the water be evaporated, and, when the composition is of a proper consistence, let it be formed into cakes, of such a size that each cake may make a pint of liquid blacking.

Frankfort- Blacking is made by a process much more simple. A quantity of the lees of wine is burnt in a well-closed vessel, and the residuum reduced to powder which, when mixed with water, is fit for immediate use ; or, if made into cakes, may be preserved for any length of time.

Ivory-black, as imported from Holland, is prepared in the. following manner : Small pieces of ivory are smeared with a little lintseed-oil, and put into a black-lead crucible ; this is covered with a similar vessel inverted, but of a smaller size, and the crevices are secured with a lute made of potter's clay and rye-flcur, so as to prevent the access of external air. Thus prepared, the whole is exposed to a red heat, not too, intense, for about half an hour, after which it is taken out and suffered to cool gradually. When cold, the charred ivory, or bones, where the former is scarce, ought to be reduced to powder, and triturated, with the addition of water, on a painter's stone, till it assumes the form of 3 smooth paste. In this state it is moulded into small cones, and allowed to dry. - Similar black may also be obtained by burning the stones of peaches, after having previously dried them and removed the kernels. This useful fact we state on the authority of Hochheimer, a German writer on general economy.