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the salt precipitated from a very concentrated strongly acid solution of brucine by potassium ferrocyanide, forms a white, crystalline powder, as seen under the microscope, which in the air quickly becomes blue. In less concentrated solutious there is no change at first, but after 12-24 hours beautiful, large, white prisms form of the same composition as the powder. The salt decomposes when heated with water with separation of hydrocyanic acid.

Potassium ferricyanide gives only normal salts. Strychnine ferricyanide, (CH2N2O2)6,H,Fe2(CN)12+12H2O, precipitated from neutral and acid solutions, forms golden-yellow, flat prisms, somewhat sparingly soluble in water to a yellow liquid. Brucine ferricyanide, (C22H26N2O4)6, H&Fe2(CN)12 + 12H2O, is precipitated from acid or neutral solutions of brucine salts as greenish-yellow spangles, sparingly soluble in water to a yellow liquid. Other alkaloids are now undergoing investigation by the authors.

Estimation of Strychnine and Brucine.-The authors have based a volumetric method on Dunstan and Short's observation that strychnine is completely precipitated from aqueous solution of its sulphate, whilst brucine is not. If a 0.5 to 1 per cent. solution of the two alkaloïds, strongly acidified with hydrochloric acid, is treated with potassium ferrocyanide until a filtered portion of the solution gives a blue stain with ferric chloride paper, the whole of the strychnine is precipitated as acid strychnine ferrocyanide, whilst the brucine remains in solution. The amount of strychnine can thus be determined by using a standard solution of ferrocyanide, 244 parts potassium ferrocyanide corresponding to 334 parts of strychnine. If the solution contain less than 0.5 per cent. the separation is too slow; also the ferric chloride paper should not be allowed to get perfectly dry before use. A mixture containing 0.145 gram strychnine and 0.036 gram brucine gave 0.148 gram of strychnine. To estimate the alkaloïds when occurring together in, say, tinctura strychni, the total weight of the two is ascertained, then, according to Schweissinger, an excess of centinormal hydrochloric acid is added and the excess determined by centinormal soda solution. The neutral solution thus obtained is concentrated sufficiently and titrated with standard potassium ferrocyanide. A mixture containing 01 gram strychnine and 0.05 gram brucine gave 0.1017 of the former and 0.04915 of the latter.

J. T.

Sulphonic Acids of Strychnine. By I. GUARESCHI (Gazzetta, 17, 109-115).-Loebisch and Schoop have recently described a monosulphonic acid of strychnine; the author finds that if strychnine is warmed with three to four times its weight of sulphuric acid, a monosulphonic acid is formed, which is best purified by means of the barium salt. The analyses, though somewhat discordant, point rather to a formula CaHa(SO3H)N2O2; it is a yellow, amorphous solid, soluble in acids and alkalis; it does not give the strychnine reaction with potassium dichromate. A solution of its ammonium salt gives precipitates with salts of silver, iron, copper, barium, and lead. Heated at 120-130° it assumes an azure-violet colour. It does not seem to be poisonous.

The disulphonic acid, C2H20(SO,H),N,O,, was not isolated, but the

barium, sodium, and potassium salts are described as amorphous solids, readily soluble in water, sparingly soluble in alcohol.

V. H. V.

Chelidonine, Chelerythrine, and Sanguinarine. By A. HENSCHKE (Chem. Centr., 1887, 243).-Chelidonine is a tertiary base; analyses of the free base, its salts and the platino- and auro-chloride, point to the formula CH19NO, + H2O.

Chelerythrine and sanguinarine seem not to be identical; the analyses of the latter, its salts and its platinochloride, point rather to the formula CHINO, proposed by Naschold, than to C19H17NO4, that given in most text-books. V. H. V.

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The Alkaloïds of Lobelia. By G. DRAGENDORFF and H. v. ROSEN (Chem. Centr., 1886, 873). The authors have isolated from the Lobelia nicotianafolia a second alkaloïd additional to the already known lobeline. It is dissolved by chloroform from solutions made alkaline with ammonia. The alkaloïds exhibit no characteristic colour reactions; they are distinguishable by their behaviour towards the group reagents. In physiological properties they are closely similar. Č. F. C.

Amount of Oxygen taken up in the Decomposition of Hæmoglobin into Albumin and Hæmatin. By M. LEBENSBAUM (Monatsh. Chem., 8, 166–179).-The amount of oxygen absorbed in the decomposition of oxyhemoglobin depends on the time allowed for the experiment, the absorption continuing after 55 days. This is probably due to the albumin which is formed taking up oxygen in presence of alkali (Nencki and Sieber, Abstr., 1882, 1307). Carbonic oxide hæmoglobin behaves in a manner similar to oxyhemoglobin, but the amount of oxygen absorbed is always less.

Oxyhemoglobin in 0.1 per cent. sulphuric acid solution, absorbs 1.1 per cent. of its weight of oxygen.

N. H. M.

Compound of Hæmatin with Nitric Oxide. By G. LINOSSIER (Compt. rend., 104, 1296-1298).-An alcoholic solution of hæmatin or reduced hæmatin readily absorbs nitric oxide, forming a brilliant red, non-dichroic solution. The absorption spectrum of this liquid is similar to that of oxhæmoglobin, and consists of two bands between E and F, the breadth of which depends on the concentration of the solution. It is difficult to distinguish this spectrum from that of oxyazotised hæmoglobin, but the latter is somewhat more intense and its two bands are about equal in intensity. When oxyazotised hæmoglobin is mixed with potash, it is converted into oxyazotised hæmatin, which gives an absorption spectrum identical with that obtained by synthesis.

Oxyazotised hæmatin is less soluble in ammoniacal alcohol than ordinary hæmatin, and reducing agents have no action on this solution. The oxygen of the air converts it into hæmatin and ammonium nitrite. If the solution thus converted into hæmatin by the action of oxygen is treated with a reducing agent, it first forms reduced hæmatin and then oxyazotised hæmatin. The reducing agent acts on the hæmatin and also on the ammonium nitrite, converting the former

into reduced hæmatin, liberating nitric oxide from the latter. The reduced hæmatin and nitric oxide at once combine to form oxyazotised hæmatin, which is not further affected by the reducing agent.

The author points out that hæmatin should by analogy be called oxyhæmatin, whilst the name hæmatin strictly belongs to the compound commonly known as reduced hæmatin (Hoppe-Seyler's hæmochromogen). He proposes to change the names in this way, in order that oxyhæmatin and hæmatin may correspond respectively with oxyhemoglobin and hæmoglobin. C. H. B.

Melanin. By M. MIURA (Chem. Centr., 1887, 250). To prepare melanin, an emulsion of a melanotic spleen is diluted with water and treated with calcium chloride and sodium phosphate. The precipitate formed contains the colouring matter, and after frequent washings at 40° is treated with a powerful digestive fluid until the solution ceases to give the peptone reaction. The residue is treated with soda, and washed to remove the nucleïn and fatty acids, and finally treated with alcohol and ether. The melanin forms a brownish-black powder, possessing the properties and composition of the hippomelanin of Berdez and Nencki. Experiments showed that the urine of animals into which melanin had been injected, gave the melanogen reaction. As the injection of melanin produces no increase in the indican reaction of the urine, it is probable that the dye formed in the air or on oxidation is analogous to the dye obtained by Pribram from the urine of a patient suffering from a melanotic tumour, which is allied to or identical with the melanin of Dressler. V. H. V.

Physiological Chemistry.

Action of Oxygen on Animals. By B. W. RICHARDSON (Chem. News, 55, 253).--According to experiments described in this paper, whilst an atmosphere of pure, freshly-made oxygen gas constantly renewed has no narcotic effect on animals, the result is quite otherwise if the oxygen that has passed through the chambers containing the animals be used a second time, and this even when the gas has been dried, and freed from carbonic acid, ammonia, and all appreciable impurities before being returned. In this case the animals become drowsy, and, as the experiment proceeds, the drowsiness passes into a perfectly quiet sleep, which ends in death after several repetitions of the process, although by no chemical tests can any difference be discovered between the lethal and the freshly-prepared oxygen. But the gas that has thus become "devitalised " can readily be "revitalised " by electrical brush discharges from the positive pole of a frictional machine. The lethal oxygen supports combustion as vigorously as ordinary oxygen, and supports life in cold-blooded animals.

R. R. Composition of Blood, Liver, and Flesh under varying Conditions. By H. WEISKE and others (Bied. Centr., 1887, 315

318). The action of acidified food on the composition of portions of a lamb was examined. Three lambs of like age were chosen, of which one (3) was immediately killed and analysed, whilst the other two were permitted to live for another six months; but whilst one (1) received ordinary hay, the hay which was given to the other (2) was moistened with dilute sulphuric acid. Analyses of the bones, &c., of these lambs after death showed that the bones of lamb (1) contained 2 per cent. more mineral matter than those of (2), and that this 2 per cent. consisted principally of lime and phosphoric acid. The dry matter of the blood of all three showed no appreciable difference, and the same may be said for the liver, but in the flesh, although nearly all constituents are present in like quantities, the lime in (1) was double in quantity. E. W. P.

Animal Nutrition. By J. W. SANBORN (Bied. Centr., 1887, 383 -386).-Two sets of steers were fed with Timothy hay and with straw, hay, and meal. The result was that an almost like increase in live-weight took place; it was further found that as the time proceeded so was a larger amount of food necessary to produce 1 lb. increase in weight of the skeleton of the animal, although at the same time the nutrient ratio varied considerably, also the increase in fat seemed to be the same. Ensilage seemed to affect the quantity of cream in milk. E. W. P.

Variations in the Proportion of Phosphoric Acid in Milk. By. A. ANDOUARD (Compt. rend., 104, 1298-1300). The proportion of phosphoric acid in milk diminishes from the beginning to the end of lactation, the degree of reduction varying with different animals. The amount of fat, and especially of sugar, diminishes at the same time. Out of four cows, two showed an increase in the proportion of caseïn, and two a decrease. The increase in the total solid matter during lactation is not a constant quantity. The age of the cows affects only the quantity of milk given, the youngest giving the least. Contrary to the statement of Kroemer, green fodder gives better results than dry fodder. The best of the foods used in the west are cabbages and legumes; next in order of merit come potatoes, swedes, beetroots, and maize. The abundance and composition of the milk appears, however, to depend mainly on the individuality of the animal. C. H. B.

Excretion of Urea and Uric Acid from the Human System. By MARES (Chem. Centr., 1887, 339–340).—The author has conducted a series of experiments on the effect produced by starvation on the proportion of urea and uric acid excreted from the human system. As a result from 21 persons it follows that in a state of starvation, a constant quantity of uric acid is excreted within a given time without reference to the quantity of nitrogen excreted within the same period. The quantity of uric acid is conditioned by the age of the individual, being diminished with greater age, but it is not influenced by the greater or less quantity of meat taken by the individual before starvation. The quantity of nitrogen, however, does

not depend on this latter condition, and varies as much as 120 per cent. within the same interval of time, increasing at the sixth to ninth hour after a meat meal, and reaching its maximum at the 24th hour. The explanation given of the results is as follows:-The uric acid is a product of living protoplasm, whilst the urea is derived from absorbed albuminoïds. In a state of rest, the protoplasm produces the uric acid, whilst the quantity of urea changes according to the greater or less quantity of albuminoïds absorbed. With an albuminoïd diet, the protoplasmic cells of the digestive tract are called into instant action, whilst the protoplasm is decomposed for the production of the digestive fluids; the quantity of uric acid is accordingly increased. So soon as the cells are at rest, the production of uric acid decreases, the resorption of the albuminoïds begins, and concomitantly the formation of urea. Experiments are given in proof of this point. If then uric acid is considered as a product of decomposition of protoplasm, the quantity of the acid eliminated may be taken as a measure of the amount of the decomposition.

V. H. V.

Hydroxybutyric Acid in Diabetic Urine. By WOLPE (Chem. Centr., 1887, 277-278).-The author has examined the urine of 10 diabetic patients for ammonia, hydroxybutyric acid, and acetone. The results show that the proportions of ammonia and hydroxybutyric acid do not vary concomitantly. After a dose of sodium carbonate, the proportion of ammonia is diminished or even disappears, but hydrochloric acid produces sometimes no effect and sometimes an increase, whilst the proportion of hydroxybutyric acid is not thereby diminished. A flesh diet produces an increase of both constituents. Apparently there is no fixed relation between the quantities of acetone and hydroxybutyric acid eliminated; however, the proportion of acetoacetic acid, as shown by the ferric chloride test, and of hydroxybutyric acid, vary in a parallel degree. There is also no relation between the quantity of sugar and the other pathological products. In a case of coma diabeticum, a gas analysis of blood from the veins gave 19.5 instead of 35 volumes per cent. of carbonic anhydride.

V. H. V. Physiological Action of Chlorinated Ethyl Sulphides. By V. MEYER (Ber., 20, 1729-1731).-Dichlorethyl sulphide, S(C2H,Cl)2, causes intense inflammation and suppuration when in contact with the skin or when breathed. The monochloro-derivative SEt C2H,Cl, shows similar but feebler action, whilst ethyl sulphide is without action. From this it follows that in these substances the physiological action is entirely and directly dependent on the chlorine. A. J. G.

Physiological Action of Tertiary Alcohols on the Animal Organism. By B. M. SHAPIROFF (Vrach, 19, 1887, 388-389).— Dimethyl ethyl carbinol, when introduced under the skin of a frog, in quantities of from 0001 to 0.005 gram, produces first stupor (depression of the cerebral hemispheres) and then paralysis of the spinal cord, as shown by the arrest of the lymphatic heart, the centres for which reside in the cord. No direct effect is produced on the blood circulation. In dogs and rabbits the blood pressure is diminished,

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