THIS substance has been discovered by Scherer in the spleen and heart of man, and of cattle. In the heart it is frequently found in such quantities, as to form a precipitate when the extract by boiling water of this organ is allowed to cool. The blood of cattle also contains this substance, which has moreover been discovered in larger quantities in the blood and urine of patients labouring under leukæmia.

Mode of obtaining Hypoxanthine.

The organs are finely chopped and boiled in water. The solution, when strained from the fibres and coagula, is treated with baryta-water, which precipitates phosphoric acid with the baryta. The filtrate is evaporated, when the excess of baryta becomes insoluble, as carbonate. When the fluid is reduced to a small bulk, it is treated with sulphuric acid. The precipitate of sulphate of baryta now forming, throws down with it uric acid and hypoxanthine. The latter two substances are extracted by boiling solution of potash, and the solution is treated with chloride of ammonium, which precipitates uric acid, while hypoxanthine remains in solution, from which it may be precipitated by a current of carbonic acid gas.

Physical and Chemical properties.

Hypoxanthine appears as an indistinctly crystalline powder, which may be triturated without assuming the glistening surface of wax. It is soluble in 1090 parts of cold, and in 180 parts of boiling water. The watery solution is without influence on vegetable pigments. It is slightly soluble in boiling alcohol, falling down from the solution on cooling. In boiling nitric acid it is soluble with effervescence; and on cooling of the solution, white crystals appear, which most probably are a product of decomposition.

When the solution in nitric acid is gently evaporated, it leaves a residue of an intensely yellow colour, which by treatment with caustic potash becomes orange.

It is almost insoluble in cold hydrochloric acid, a little more soluble in the boiling acid, but forms no combination with it.

It is soluble in concentrated sulphuric acid, without the formation of charcoal or the evolution of gas.

It is soluble in caustic potash, and is precipitated from the solution by carbonic acid.

It readily dissolves in ammonia; and, when the latter evaporates, remains as a lamellated mass, with little adhesion to the walls of the vessel.

THIS substance has lately been discovered and described' by Professor A. Strecker, of Christiania, who provisionally gave it the name of sarcine. But as this name might lead to misunderstanding, by its being identical with the name of the alga, sarcina ventriculi, discovered by Goodsir in vomit, and which also occurs in the urine, I propose carnine as a temporary synonym, until the discoverer shall have definitely baptized this substance.

Carnine occurs in the juice of flesh, together with the several principles discovered and described by Liebig, and many others as yet undetermined. When to the mother-liquor of creatine a solution of either corrosive sublimate, nitrate of protoxyde of mercury, ammonio-chloride of zinc, or acetate of copper is added, a considerable precipitate is produced, which in every instance contains an organic base as an essential constituent. This organic base occurs in beef and horse-flesh in about equal quantities, and is also most probably an ingredient of human urine. The substance discovered by

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'Quarterly Journ. of the Chem. Soc.,' vol. x, p. 121, July, 1857.

Strecker in human urine closely resembles carnine in its compounds; the only doubt as to whether it may not be guanine, Dr. Strecker is about to decide by further analyses.

Mode of obtaining it pure.

The most advantageous method of preparing this base is by precipitation with acetate of copper. The mother-liquor of the creatine crystals is diluted, and mixed with a dilute solution of copper. The copious precipitate thus produced is decomposed by sulphuretted hydrogen (hydrothion), when the base remains in solution. To remove colouring matter, the solution is boiled with hydrated oxyde of lead, which also takes up a small quantity of carnine. The filtrate from the lead is treated with hydrothion, and after filtration evaporated, when carnine is obtained in a crystalline form.

Physical and Chemical characters.

From its warm saturated solution, carnine, on cooling, is deposited as a white, indistinctly crystalline powder, frequently, however, adhering as a dense crust to the sides of the vessel. It is soluble in 300 parts of water of 15° C. (60° F.) temperature, and in 78 parts of boiling water; it requires 900 parts of boiling alcohol for solution. The solutions do not change the colour of litmus paper, and have not got any very characteristic taste. In hydrochloric acid, ammonia, and potash, carnine dissolves much more readily than in cold water; less readily in dilute nitric and sulphuric acid. largely soluble in concentrated nitric and sulphuric acid, without discoloration or evolution of gas.

In a boiling solution of carnine, basic acetate of lead produces a precipitate. From its watery solution, carnine is further precipitated by ammonio-chloride of zinc, by cadmium salts, the mercury salts already mentioned, and the salts of many other metals. Caustic alkalies, including baryta, dissolve carnine; from these solutions it is mostly precipitated by a current of carbonic acid gas. From these characters, and the nature of its combinations, it is evident that carnine is a base.

Compounds.

Carnine forms well defined combinations with acids, metallic oxydes, and salts.

Hydrochlorate of carnine. CH ̧Ñ‚О2, HCl + 2Aq.-The

solution of sarcine in boiling concentrated hydrochloric acid, deposits, on cooling, colourless crystalline plates of the forementioned composition. When, however, the solution of hydrochlorate of sarcine in water is repeatedly evaporated to dryness on the water-bath, a residue is at length obtained, containing no hydrochloric acid. Water has therefore a decomposing influence upon this salt.

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Hydrochlorate of carnine and bichloride of platinum. C10H4 NO, HCl, PtCl.-On adding a solution of bichloride of platinum to a concentrated solution of crystals of hydrochlorate of carnine, this platinum salt is deposited in yellow crystalline masses, which are sparingly soluble in cold water, but readily dissolve in a higher temperature.

Nitrate of carnine.-The solution of carnine in concentrated nitric acid, deposits, on standing, transparent, colourless crystals (apparently rhombic octahedra) of nitrate of carnine, which, on exposure to air or water, become white and opaque, without any alteration of shape.

Sulphate of carnine. The solution of carnine in concentrated sulphuric acid, deposits, on standing, or by addition of alcohol, colourless, needle shaped crystals of sulphate of carnine, which, on coming in contact with water, crumble to a white powder.

Carnine, when treated with concentrated acids at a temperature of 240° F. (100° C.), does not undergo any decomposition. Its solution, when mixed with aqua regia and evaporated on the water-bath, leaves a residue, which consists mainly of unchanged carnine.

Carnine and baryta. CH,Ba,N,O2 + 4Aq.-A solution of carnine in baryta-water, on addition of a larger quantity of baryta-water, deposits transparent colourless crystals of carnine-baryta. From the solution of this salt the baryta may be precipitated by a current of carbonic acid gas.

Carnine and oxyde of silver. CH2AgNO2 + 2Aq.-On adding a solution of sarcine to an ammoniacal solution of nitrate of silver, a flocculent precipitate, quite insoluble in water and ammonia, is obtained, which on drying becomes a hard mass, like alumina.

Carnine and nitrate of silver. CH4NO2, AgO, NO,.—A solution of carnine in water, when mixed with a solution of nitrate of silver, forms a flocculent precipitate, which is insoluble in dilute nitric acid at the ordinary temperature. It is, however, completely soluble in boiling concentrated nitric acid, and from this solution is, on cooling, deposited in colourless scaly crystals, and so completely, that the filtrate scarcely yields any precipitate on addition of hydrochloric acid.