pulverize the ground, and deprive it of its tenacity.—See Land and Manure.
Black Lead. See Lead.
BLACK LEATHER is that which, having passed through the hands of the carrier, after being scored and rubbed three times on the grain side with copperas-water, acquires a black colour, instead of the russet, as left by the tanners.—See Leather.
BLACK-LEGS, a name given by the Leicestershire breeders to a disease incident to calves and sheep. It is a kind of gelatinous humour, which settles between the skin and flesh of the neck, and not unfrequently in their legs. To remove this troublesome complaint, we conceive that the sal-ammoniac dissolved in the smallest possible quantity of water, and applied to the parts affected, by means of proper compresses, or even simple friction, conjoined with suitable exercise, would be the most effectual remedy.
BLACK TIN, in mineralogy, a term given to tin-ore when it is ready to be melted into metal, after having been well stamped, washed, and dressed. It is taken up from the washing-troughs in the form of a tine black powder, and from this circumstance is called black tin; two pounds of which being melted, will produce one pound of white tin. The principal mines from which this useful metal is obtained in Britain, are those in Cornwall.—See Tin.
BLACK WADD, in mineralogy, is a kind of ore of manganese, remarkable for its property of taking fire, when mixed with a certain proportion of lintseed-oil. It is found in Derbyshire, and is a useful ingredient in paints; for on being ground with a large quantity of oily matter, it loses the property above-mentioned.
BLACKBERRY, the fruit of the common bramble, or Rubus fruticosus, L.—See Bramble.
These berries, when eaten immoderately, and too frequently, are apt to produce the most violent effects, as fever, delirium, &c.
BLACKING, in general, signifies a factitious black; as lamp-black, shoe-black, &c. 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 metropolis, 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 blue, 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,
