PENCIL, is also an instrument used in drawing, writing, &c. made of long pieces of black lead or red chalk, placed in a groove cut in a slip of cedar; on which other pieces of cedar being glued, the whole is planed round, and one of the ends being cut to a point, it is fit for use.
Black lead in fine powder, stirred into melted sulphur, unites with it so uniformly, and in such quantity, in virtue perhaps of its abounding with sulphur, that though the compound remains fluid enough to be poured into moulds, it looks nearly like the coarser sorts of black lead itself. Probably the way which Prince Rupert is said to have had, mentioned in the third volume of Dr. Birch's History of the Royal Society, of making black lead run like a metal in a mould, so as to serve for black lead again, consisted in mixing with it sulphur or sulphureous bodies.
On this principle the German black lead pencils are said to be made; and many of those which are hawked about by certain persons among us are prepared in the same manner: their melting or softening, when held to a candle, or applied to a red hot iron, and yielding a bluish flame, with a strong smell like that of burning brimstone, betrays their composition; for black lead itself yields no smell or fume, and suffers no apparent alteration in that heat. Pencils made with such additions are of a very bad kind; they are hard, brittle, and do not cast or make a mark freely either on paper or wood, rather cutting or scratching them than leaving a coloured stroke.
The true English pencils (which Vogel in his mineral system, and some other foreign writers, imagine to be prepared also by melting the black lead with some additional substances, and casting it into a mould) are formed of black lead alone sawed into slips, which are fitted into a groove made in a piece of wood, and another slip of wood glued over them; the softest wood, as cedar, is made choice of, that the pencil may be the easier cut; and a part at one end, too short to be conveniently used after the rest has been worn and cut away, is left unfilled with the black lead, that there may be no waste of so valuable a commodity. These pencils
are greatly preferable to the others, though seldom so perfect as could be wished, being accompanied with some degree of the same inconveniences, and being very unequal in their quality, on account of different sorts of the mineral being fraudulently joined together in one pencil, the fore part being commonly pretty good, and the rest of an inferior kind. Some, to avoid these imperfections, take the finer pieces of black lead itself, which they saw into slips, and fix for use in port crayons: this is doubtless the surest way of obtaining black lead crayons, whose goodness can be depended on.