* NITRIC ACID, (aquafortis) is obtained by distilling two parts of sulphuric acid, together with one part of salt-petre, _oz._ 12 * NUT GALLS, are formed on the leaves of a species of oak, _oz._ 6 * OLIVE OIL, (sweet oil,) _oz._ 3 * OIL OF CINNAMON, extracted from cinnamon by distillation, _oz._ 75 * OIL OF ROSEMARY, procured also by distillation, _oz._ 25 * ORANGE LEAD, a scarlet pigment similar to red lead, _oz._ 3 * OXIDE OF MANGANESE, a black powder consisting of a metal combined with oxygen, _oz._ 10 * PHOSPHORUS, a simple substance procured from bones; its greatest peculiarity is extraordinary combustibility, _oz._ 200 * PHOSPHURET OF LIME, a combination of lime and phosphorus, _oz._ 200 * PLUMBAGO, (black lead) a carburet of iron, _lb._ 16 * POTASSIUM, the metallic base of potass, may be readily obtained from pearl ash by any one who has a galvanic apparatus, * PRUSSIATE OF IRON, (prussian blue) may be formed by adding prussiate of potass, to a solution of copperas, _oz._ 25 * PRUSSIATE OF POTASS, a combination of potass and prussic acid, _oz._ 50 * PUMICE STONE, _lb._ 12 * RED LEAD, (minium) is obtained by melting lead in an open vessel, and exposing it in that state to the action of the atmospheric air, _oz._ 3 * RED OCHRE, (spanish brown) a native oxide of iron, _lb._ 6 * ROSIN, the resinous part of turpentine, _lb._ 6 * SILVER BRONZE, _pwt._ 50 * SILVER LEAF, _book_ 30 * SLIP BLUE, (wet blue) an aqueous preparation of prussian blue, _lb._ 30 * SPIRITS OF TURPENTINE, (oil of turpentine) is procured by distilling common or crude turpentine; the residuum is rosin, _pt._ 12 * SUB-ACETATE OF COPPER, (verdigris,) _oz._ 3 * SUB-CARBONATE OF POTASS, (pearlash) potass refined by calcination, _lb._ 12 * SULPHATE OF COPPER, (blue vitriol, roman vitriol,) _oz._ 3 * SULPHATE OF IRON, (copperas, green vitriol,) _oz._ 6 SULPHATE OF LIME, (plaister of paris, alabaster, gypsum,) * SULPHATE OF ZINC, (white vitriol,) _oz._ 3 * SULPHUR (brimstone) is generally found combined with ores of metals, _oz._ 3