_Note._--All these were unknown to the ancient chemists.--A. SECT. XL.--_Observations upon Saccholactic Acid, and its Combinations._ A species of sugar may be extracted, by evaporation, from whey, which has long been known in pharmacy, and which has a considerable resemblance to that procured from sugar canes. This saccharine matter, like ordinary sugar, may be oxygenated by means of nitric acid: For this purpose, several portions of nitric acid are distilled from it; the remaining liquid is evaporated, and set to cristallize, by which means cristals of oxalic acid are procured; at the same time a very fine white powder precipitates, which is the saccholactic acid discovered by Scheele. It is susceptible of combining with the alkalies, ammoniac, the earths, and even with the metals: Its action upon the latter is hitherto but little known, except that, with them, it forms difficultly soluble salts. The order of affinity in the table is taken from Bergman. TABLE _of the Combinations of Formic Acid, with the Salifiable Bases, in the Order of Affinity._ _Bases._ _Neutral Salts._ Barytes Formiat of barytes. Potash potash. Soda soda. Lime lime. Magnesia magnesia. Ammoniac ammoniac. Oxyd of zinc zinc. manganese manganese. iron iron. lead lead. tin tin. cobalt cobalt. copper copper. nickel nickel. bismuth bismuth. silver silver. Argill argill. _Note._--All unknown to the ancient chemists.--A. SECT. XLI.--_Observations upon Formic Acid, and its Combinations._ This acid was first obtained by distillation from ants, in the last century, by Samuel Fisher. The subject was treated of by Margraff in 1749, and by Messrs Ardwisson and Ochrn of Leipsic in 1777. The formic acid is drawn from a large species of red ants, _formica rufa, Lin._ which form large ant hills in woody places. It is procured, either by distilling the ants with a gentle heat in a glass retort or an alembic; or, after having washed the ants in cold water, and dried them upon a cloth, by pouring on boiling water, which dissolves the acid; or the acid may be procured by gentle expression from the insects, in which case it is stronger than in any of the former ways. To obtain it pure, we must rectify, by means of distillation, which separates it from the uncombined oily and charry matter; and it may be concentrated by freezing, in the manner recommended for treating the acetous acid. SECT. XLII.--_Observations upon Bombic Acid, and its Combinations with Acidifiable Bases[52]._