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Mylius's desoxycholic acid (Abstr., 1886, 480) is identical with hydrated choleïc acid.

Cholic and choleïc anhydrides are obtained by heating the acids at 165°.

The proportion of choleïc to cholic acid in ox-gall is about 1 to 3.3 (comp. Ber., 18, 3043).

N. H. M.

Crystalline Form of Choleïc Acid. By P. LATSCHINOFF (Ber., 20, 1053—1056).—Anhydrous choleïc acid crystallises in the rhombic system (hemihedric), a b c = 1: 05057: 1-85979, a being the macro-axis, b the brachy-axis, and c_ the principal axis. The faces observed are OP, Þ∞, 2P, P, and coPcs.

Choleïc acid (with 1 mol. H2O) crystallises in the quadratic system, a : c = 1 : 2·48282 (c being the length of the principal axis). The crystals are a combination of three quadratic pyramids.

N. H. M.

Action of Oxidising Agents on Albumin from Eggs. By C. WURSTER (Ber., 20, 1030–1033).-Fresh unfiltered albumin was treated with 1 per cent. sodium chloride solution and 1 per cent. lactic acid and shaken for 10 minutes; it was then mixed with hydrogen peroxide, placed in a eudiometer over mercury, and heated at 37-40° in an incubator. Coagulation generally took place without evolution of gas; oxygen was in all cases absorbed, although in small quantity. When the product, to which the name egg-caseïn is ascribed, is digested in the eudiometer with pepsin and hydrochloric acid at 37°, no change in the volume of the oxygen could be observed.

Egg-casein is readily soluble in dilute ammonia, and is precipitated on adding an acid. When treated with ammonia in presence of hydrogen peroxide, it is converted into a sparingly soluble, transparent, gelatinons substance. The latter dissolves slowly in aqueous soda. It has the property of completely precipitating aniline dyes from their solutions. When dried, it becomes horny and insoluble.

N. H. M.

Behaviour of Sodium Nitrite towards Albumin from Egg and the Colouring Matter of Blood. By C. WURSTER (Ber., 20, 1033-1039).-Albumin is not affected by and 1 per cent. sodium nitrite solution at 37°. When the solution is made acid with lactic acid, it acquires a yellow colour, and coagulation takes place. When exposed to air in an incubator the colour darkens; when filtered and dried the precipitate becomes first orange-red, then fox-red.

The author showed previously that fresh blood does not decompose hydrogen peroxide in presence of lactic or acetic acids. The colouring matter of the blood is changed to a brownish-black substance, which is slowly decolorised by hydrogen peroxide, showing the various shades from dark-brown to white. No red colour is produced.

It is suggested that the colour of blonde and dark-brown hair may be due to the action of hydrogen peroxide on the colouring matter of the blood, whilst that of red and black hair is produced by the action of nitrous acid on the albumin and on the colouring matter of the blood respectively. The sudden becoming grey of

hair is accounted for by hydrogen peroxide being forced up into the hair, where it would give rise to an evolution of oxygen.

Observations made by the author on the formation of pigment in the skin under the influence of the sun are described.

N. H. M.

Physiological Chemistry.

Period required for Digestion in the Pig. By ELLENBErger and HOFMEISTER (Bied. Centr., 1887, 158-160).-The emptying of the stomach commences in 18 to 24 hours after feeding, and is completed in 36 hours, but a portion of the less digestible food generally remains in the large intestine, and may remain there for eight days; hence it is here that sparingly soluble poisons will be found. A portion of the meal remains in the stomach until the next meal is given, provided the period of time between the two meal times is not too lengthy, and then, if the meal is ample, all the residue of the former meal will be removed from the stomach, but if otherwise, a portion will remain. The first portions of the meal enter the small intestine within three hours, and in three hours more the cæcum is filled. The food remains but a short time in the smaller, whilst it remains a long time in the larger intestine. The reaction of the contents of the intestines is as follows:-Contents of the stomach, acid; only at the commencement of digestion and in the neighbourhood of the cardiac is it alkaline. The first portion of the small intestine (two-thirds or five-sixths) has an acid reaction, the remainder is alkaline; the contents of the duodenum are acid, the ileum (Hüftdarm) alkaline, and the jejunum variable. E. W. P.

Behaviour of the Three Isomeric Nitrobenzaldehydes in the Animal Body. By N. SIEBER and A. SMIRNOW (Monatsh. Chem., 8, 88-93).—The experiments were made on dogs. 2 to 3 grams of each of the isomeric nitrobenzaldehydes were administered daily to dogs; this was continued for eight days, and then it was stopped for eight days, being given again at the end of that time. This treatment was continued for two months.

The results showed that all three nitrobenzaldehydes were oxidised in the organism to the corresponding nitrobenzoic acids, but were excreted in different forms. Paranitrobenzaldehyde is excreted as paranitrohippuric acid carbamide, metanitrobenzaldehyde as metanitrohippuric acid, and orthonitrobenzaldehyde as orthonitrobenzoic G. H. M.


Therapeutic Action of Methylal. By A. MAIRET and COMBEMALE (Compt. rend., 104, 1022-1024).-The authors have adminis tered methylal in a large number of cases of mental derangement of various kinds. The results were highly satisfactory except in the case

of alcoholic frenzy, and the commencement of simple insanity with nocturnal agitation. The dose required is 5 to 8 grams, and the effect is purely hypnotic. The action on the brain is transient, and there is no after-depression, and no interference with nutrition or any other functions.

The system somewhat rapidly becomes accustomed to the drug, which then ceases to produce any useful hypnotic effect, and in order to obtain the best results its administration must be discontinued for two or three days. C. H. B.

Chemistry of Vegetable Physiology and Agriculture.

Decomposition of Carbonic Anhydride by Chlorophyll. By PRINGSHEIM (Bied. Centr., 1887, 168).-The author combats Regnard and Timiriazeff's conclusions drawn from their experiments on chlorophyll (Abstr., 1886, 254 and 266), but considers that it is not the chlorophyll colouring matter which decomposes carbonic anhydride, but a compound which by reduction of the anhydride is converted into chlorophyll. If the author is correct, then the absorption-bands of chlorophyll between B and C stand in no relation to the decomposition of carbonic anhydride, seeing that the compound which according to Timiriazeff decomposes carbonic anhydride does not show or produce these bands. E. W. P.

Physiological Rôle of Vine Leaves. By H. MUELLER (Ann. Agronom., 13, 140).-A large number of leaf-bearing shoots should be sacrificed during the ripening of the fruit. These leaves require a large quantity of sugar for their development and for the support of their respiration. In removing the old leaves during the ripening of the fruit, too great a loss of assimilating tissues need not be feared, because the old leaves have only feeble assimilating power, and are moreover in the shadow of the upper leaves. The quantity of water contained in the leaves exercises a considerable influence on the amount of sugar they form. If two shoots are cut off and placed in darkness until all the starch has disappeared, then one of these simply placed in water, and the other injected with water under pressure, the latter will form starch much more abundantly than the former. The transformation of starch into sugar is similarly affected.

The vessels of climbing plants constitute important reserves of water, and in cultivating the vine as it is done in France these are lost. The vine cultivated in France also appears very inactive in habit, since the leaves do not commence the work of assimilation until June, whereas the American vines commence much earlier. Perhaps it is on this account they resist the phylloxera better.

J. M. H. M.

Is Nitric Acid Formed in the Organism of Higher Plants P By U. KREUSLER (Ber., 20, 999-1001).-Potatoes were grown in saw-dust treated with a solution containing suitable nourishment free from nitrogen. The plant was then tested for nitrates with negative results. Hence it is concluded that the high percentage of nitrates found in the potato plant at certain times is not the product of any process connected with vegetation. N. H. M.

Intermolecular Respiration. By S. JENTYS (Ann. Agronom., 13, 138). Experiments on wheat, radish, and Philadelphus coronarius show that it is much easier to obtain intramolecular respiration in plants from amylaceous seeds than in those from oleaginous seeds; it takes place when the pressure of oxygen falls to 38 mm. When there is no oxygen, the first disengage much more carbonic anhydride than the second. Germinating seeds are much more sensitive to the diminution in the pressure of oxygen than older plants. With the buds of the Philadelphus, a very strong diminution in the oxygen pressure does not produce intramolecular respiration. The author admits with Detmer that it is the non-nitrogenous products of the decomposition of albuminoïds which give rise to both sorts of respira J. M. H. M.


True Nature of Starch Cellulose. By GRIESSMAYER (Bied. Centr., 1887, 190-192).—The investigation was undertaken to ascertain the true nature of the coating said to surround the true grains of starch (granulose). Meyer considers this coating not to consist of a compound present in the unaltered granule, but to be the result of change of the starch; this substance is obtainable by the action of acid, pepsin, &c., and is convertible into dextrin, and finally into saccharine compounds. This amylodextrin is with difficulty separated, unless it crystallises in spherocrystals; these crystals then react on polarised light in the same manner as starch grains, only that the dark cross is not orthagonal, but diagonal. The coatings can be obtained by the following method: 1000 grams of potato starch is allowed to remain for 100 days in 6 litres of 12 per cent. hydrochloric acid, the coatings are then separated and filtered off, and washed with water: when dried they weigh about 300 grams, and when boiled in water they dissolve almost entirely; there, however, remains a small portion of cellulose tissue, fat, &c.; from the solution, cold causes the dissolved compound to separate, forming spherocrystals of amylodextrin, E. W. P.

Sugars of the Soja Bean. By T. MORAWSKI and J. STINGL (Monatsh. Chem., 8, 82-84; compare Abstract, 1886, 829).—The sugars, which occur in the soja bean to the extent of 12 per cent., were examined by precipitation with barium hydroxide and decomposition of the precipitate with carbonic anhydride. In this way, a light-coloured syrup was obtained, which was dissolved in 90 per cent. alcohol, and the solution fractionally precipitated with ether. Well-defined crystals of sucrose were obtained from the two last fractions with ether; this sugar was identified by polarisation before and after inversion. The uncrystallisable fractions contained sugars

which could not be identified with certainty; the rotatory power was higher than that of sucrose, and the sugars were more difficult to invert. The amount of sugar found, both by Fehling's solution and by polarisation, after inversion, was too small for the amount of sugar originally present. G. H. M.

Fat of the Soja Bean. By T. MORAWSKI and J. STINGL (Monatsh. Chem., 8, 85-87; compare Abstract, 1883, 1024).-The authors conclude from the results of the "saponification value," the "iodine value," and the determination of the amount of free fatty acid, that the soja bean oil lies between marrow-seed oil and sesame oil. It most resembles the former. The sp. gr. of the fat is 0.9270 at 15°. G. H. M. Russian Black Earth. By E. BRÜCKNER (Bied. Centr., 1887, 148-149).—In many districts in West-South Russia soil is found containing a large percentage of humus (2 to 19 per cent.). Dokutschajef finds, as a rule, that this deposit consists of two layers; the upper, 0.5 m. thick, being homogeneous, fine-grained, and of a clayey consistency, and permeated by a thick network of grass roots; the lower layer of a similar character, but pierced with cavities and passages. No satisfactory explanation has as yet been given of the formation of this soil. E. W. P.

Value of the Phosphoric Acid in Thomas Slag. By M. MARCKER (Bied. Centr., 1887; 148-156).—Ground Thomas slag was compared with superphosphate and precipitated phosphates as manure for barley, oats, potatoes, and sugar-beet. The superphosphate yielded the highest results, and no difference in the composition of the crop as occasioned by the varieties of phosphate could be detected. On moorland soils, slag was found to surpass the other forms of phosphate, or at least to equal them. E. W. P.

Analytical Chemistry.

New Gas Burette. By B. FRANKE (J. pr. Chem. [2], 35, 259262). The burette holds exactly 100 c.c., and is closed at one end by a small stopcock, at the other end by a wide bore stopcock leading into a wide tube holding some 50 c.c.; this serves to introduce the absorption reagent, and is closed by a stopper bearing a small stopcock. The sample of gas having been enclosed in the burette, the other half is completely filled with the absorption reagent, and the two well brought into contact by opening the wide bore stopcock and shaking; the reagent is then drained back into the reservoir, and ultimately poured out; the reservoir filled with water, and the whole being introduced into a cylinder of water, the large stopcock is opened, the pressure adjusted, and the volume read off. The apparatus is very simple and allows of very rapid estimations.

H. B..

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