The author applies these observations to a discussion of the origin and nature of the acidity of gastric juice, arriving at the following hypothesis:-Lactic acid is formed by fermentation from the mucus of the stomach, and, acting on alkaline chlorides, liberates hydrochloric acid, which is forthwith taken up in combination by the albuminoïds of the food. The sodium lactate is simultaneously assimilated. With the gradual peptonising of the albuminoïds, the hydrochloric acid is liberated. C. F. C.

Ferment Organisms of the Alimentary Canal. By N. MILLER (Chem. Centr., 1886, 580).Of the 25 micro-organisms identified by the author in the mouth, 12 were also found in the intestines, and 8 in the stomach. Although normal gastric juice is antiseptic, the conditions in the stomach are often such as to prevent contact of the organisms therewith, which then continue active. These organisms are also carried forward into the intestines by liquids which remain only a short time in the stomach.

In most cases, these organisms exert a peptonising but only seldom a diastatic action. In some cases, they induce lactic fermentation of carbohydrate solutions; in others acetic and butyric. In some instances the fermentation was attended with the evolution of carbonic anhydride and hydrogen. C. F. C.

Formation of Fat in the Dog from Carbohydrates. By J. MUNK (Bied. Centr., 1886, 748-750).—A bitch was allowed to fast for 31 days, this being the period stated by Hofmann to be necessary for the removal of all fat from the system-31 per cent. of the weight was lost. The animal was then fed with 200 grams of flesh, 100 grams of gelatin, and an increasing ration of starch and sugar in equal parts (300 to 500 grams). After 25 days the animal was killed and examined, when it was found to have increased in weight at a rate of 36 grams daily, and, taking the lowest valuation, nine-tenths (960 grams) of the whole fat found in it had been put on during the 25 days. The sources from which the fat could have been formed were three: namely, fat in the flesh given, decomposed albumin, and carbohydrates. Of the fat produced by the decomposition of albumin, there would be according to Voit and Pettenkofer 12 per cent., according to Henneberg 51 per cent.-415 grams should be formed; but this quantity must be reduced to 42 to 45 per cent. if Zuntz's method of calculating Henneberg's results is to be followed; the author therefore considers that 343 to 364 grams fat must be attributed to albumin; the fat from the meat amounted to 75 grams. However, whatever may be the quantity of actual fat from albumin, there appears to be no doubt that 788 grams (max.) 470 grams or 542 to 521 grams of fat (according to the method of calculation used), had to be sought for from other sources, namely, the gelatin and starch. The author allows for argument's sake that 338 grams might come from the gelatin (this, however, according to Voit and Pettenkofer, is inadmissible), even then 162 grams of fat must have come from the carbohydrates.

E. W. P.

Relation between the Destruction of Glucose and the Production of Animal Heat and Work. By A. CHAUVEAU and KAUFMANN (Compt. rend., 103, 974-975, 1057-1064, 1153-1159).—On comparing two organs which, under ordinary physiological conditions, have very unequal thermogenic activities, it is always found that the destruction of glucose is much greater in the organ in which combustion is most active, or, in other words, the heat developed in animal tissues, which is proportional to the amount of internal combustion, is also proportional to the quantity of glucose removed from the blood in the capillaries.

Analyses of the blood of the masseter muscle and parotid gland of the horse during a state of repose, showed that the activity of combustion in the muscle as measured by the amount of oxygen absorbed and of carbonic anhydride produced is to that in the gland as 4:57 : 1, whilst the destruction of glucose is as 5.68: 1.

During the process of mastication and insalivation, the activity of combustion in the muscle is increased by 35 times, whilst the consumption of glucose in the blood traversing the muscle is increased to almost the same extent. In the gland, the ratio between the activity of combustion at rest and in action is 60: 87, whilst the consumption of glucose is as 70: 90. In experiments of this kind, it is important to take into account not only the composition of the blood, but also the volume which traverses the organ in unit time.

Details of the method of experiment and of the analyses are given in the original papers.

Glucose is always found in the nutritive secretions, but never in any tissues except the liver. Glycogen, on the other hand, does not occur in the blood, but only in the hepatic and muscular tissues. Analyses of muscle in repose and in action confirm the statement that glycogen accumulates while the muscle is at rest, but disappears during activity. The glucose which disappears from the capillaries leaves them in company with oxygen, and is more or less completely converted into water and carbonic anhydride in the organs and tissues. The glycogen which has accumulated in the muscles provides the materials for combustion during periods of great activity when the supply of glucose is not equal to the demand. Only a portion of the glucose which disappears from the capillaries is consumed; the remainder becomes converted into muscular glycogen by dehydration, and then forms a reserve. During excessive work, the glycogen becomes hydrated and reconverted into glucose, which is consumed.

The liver is the indirect collaborator of the muscles during activity. In fact the hepatic gland performs its functions as a glycogenic organ the more actively each time that any work is done by any part of the animal economy. This is established by the fact that the blood never becomes appreciably poorer in glucose even during activity. On the contrary, there is often an excessive production of glucose, especially if the activity is localised as in mastication.

So long as the liver furnishes glucose to the blood in sufficient quantity, so long does the animal continue to develop the quantity of heat necessary for the activity of the other organs and the maintenance of the bodily temperature. When the glycogenic function of

the liver becomes enfeebled, glucose disappears from the blood-vessels, organic combustion rapidly diminishes, and death supervenes as a result of arrested calorification. C. H. B.

Origin of the Bile Colouring Matters. By H. STERN (Chem. Centr., 1886, 481).-The author's experiments were performed on pigeons. The bile-ducts being ligatured and provision being made for collecting the urine separately, by ligaturing the rectum above the entrance of the urethra, it was found that within 12 hours the urine was highly charged with these colouring matters. After death, the tissues were found to be similarly charged. In a second series of experiments, the liver was thrown entirely out of the circulation. In this case neither in the blood, urine, nor tissues were any traces of these colouring matters found. The author concludes from his experiments that these substances originate entirely in the liver substance.

C. F. C.

Active ß-Hydroxybutyric Acid. By E. KULZ (Zeit. Biol., 23, 329-339). The author has previously described the occurrence of this substance in diabetic urine. It may be prepared as follows:Diabetic urine which gives the ferric chloride reaction and is strongly lævorotatory is (after the removal of the sugar by fermentation) concentrated to a thin syrup, and neutralised with sodium hydroxide, three times as much 95 per cent. alcohol is added, which produces an abundant precipitate; from the alcoholic filtrate, the alcohol is evaporated, and more alcohol added; this is repeated until alcohol gives no further precipitate; the last traces of alcohol are removed by shaking with ether. To the residue, sulphuric acid is added, and the mixture shaken with an equal volume of ether.

The ether is driven off by heat, and the remaining brown syrup gives a precipitate with lead acetate, which is filtered off. From the filtrate, excess of lead is removed by sulphuretted hydrogen; barytawater is added, and the barium salt of the acid is obtained in solution. Urea is then precipitated by means of mercuric nitrate, excess of mercury being removed by treatment with sulphuretted hydrogen. From the solution of the barium salt, the silver salt is obtained by adding a solution of silver sulphate; the barium sulphate is removed, and on concentration crystals of the silver salt are obtained and purified by recrystallisation. The free acid is obtained by decomposing the solution of the silver salt with sulphuretted hydrogen. The specific rotatory power of this acid is [a]p =234. The ammonium salt has the specific rotation denoted by [a]p D= 16.3.

Minkowski's test for this acid in urine (Arch. exp. Path. u. Pharmak., 18, 41) is not regarded as trustworthy; and the obtaining of crystals of a-crotonic acid, on adding sulphuric acid, is preferred. The presence of a substance which rotates polarised light to the left, which gives the ferric chloride reaction, and which is not precipitable by lead acetate, may be taken as strong presumptive evidence of the presence of B-hydroxybutyric acid. Benzoic acid (from the decomposition of hippuric acid), salicylic acid, and phenol, might possibly be confounded with it; methods of avoiding such a mistake are given. The

acid does not appear to be present in the urine of healthy men or animals; but it occurs in unhealthy urines not only in cases of diabetes, but also in cases of scarlet fever, measles, diphtheria, scurvy, and in certain mental affections. W. D. H.

Physiological Action of Convolvulin and Jalapin. By G. DRAGENDORFF (Chem. Centr., 1886, 589).-The question of the excretion of these glucosides after being taken into the human stomach has been investigated by Bernatzik (Wiener med. Jb., 1862–63); traces only were found in the fæces, none in the urine. This result was confirmed by Köhler and Zincke (W. Jb. für Pharm., 32, 1); who, however, succeeded in isolating these purgatives from the stomach and intestines. The author has repeated these investigations, adopting a simplified method of examination of the parts for the glucosides and products of decomposition (convolvulic and jalapic acids), based on extraction with chloroform. 0.5 gram of the glucosides was the quantity given, cats being taken as the subject of the experiments.

The author confirmed the previous results in regard to the nonexcretion of the drugs in the fæces and urine. The animals were killed after the lapse of four hours, and the organs examined; appreciable quantities of the drugs were found in the stomach and small intestines, less in the duodenum, traces only in the lungs and pancreas. No evidence was obtained that the glucosides are converted into the derived acids. C. F. C.

Chemistry of Vegetable Physiology and Agriculture.

Bacterial Life in Relation to Oxygen. By P. LIBORIUS (Chem. Centr., 1886, 579). The author classifies these organisms as follows:

(1.) Exclusively anaerobic: amongst these there are many which multiply without attendant fermentation.

(2.) Exclusively aerobic: reduced to inactivity by deprivation of oxygen. This class includes:-B. fluorscens liquifaciens, B. aerophilus, B. cyanogenus, B. fuscus, B. aquatilis fuscus, B. subtilis. With excep

tion of the first-named, which appears to determine a special fermentation of albuminoïds with formation of volatile fatty acids, the bacteria of this group have not been closely studied in relation to fermentation.

(3.) Optionally anaerobic activity lowered, but not suspended, by deprivation of oxygen. This class includes all the pathogenic organisms: B. anthracis, B. typhi abdom. From this general view of the conditions of bacterial life, and from his own special investigations, the author concludes that an attendant fermentation is not an essential condition of anaerobic activity in the sense in which it has been so stated by Pasteur and Nägeli. C. F. C.

Wine and Brandy from Raspberries and Strawberries. By A. ROMMIER (Compt. rend., 103, 1266-1268).-The ferment of the raspberry, which has been described by Le Bel as Levure wurtzii, is not able to convert the whole of the sugar of the raspberry into alcohol. In order to ascertain if this is due to want of activity in the ferment, or to the action of some constituent of the fruit, energetic ellipsoïdal wine yeast was mixed with the liquid. Fermentation then proceeded rapidly, and not only the sugar existing in the fruit, but two or three times the quantity of added sugar, was converted into alcohol. Raspberry brandy, obtained by distilling the wine, is very aromatic, and has the odour of raspberries, then becomes slightly smoky, but finally acquires a very fine bouquet.

The ferment of strawberries is more active, but fermentation is accelerated by the addition of ellipsoïdal wine yeast. Strawberry wine from French strawberries is less acid than that from raspberries, and keeps well, provided that it contains 16 per cent. of alcohol. The brandy has a strawberry bouquet, which becomes stronger after some time, but does not alter in character.

The flavour of the brandy from English strawberries, although made with a double quantity of added sugar, is still so strong as to be unpleasant, but if diluted with water the strawberry bouquet develops in perfection, a fact which indicates that more sugar might be added with considerable advantage.

Levure wurtzii and others, such as L. apiculatus, have no inversive properties, and can therefore act only on invert sugar, and are unable to alter the saccharose which also exists in the juices of many fruits. A higher yield of alcohol can be readily obtained by adding an inversive ferment like the ellipsoïdal yeast of wine. C. H. B.

Zymotic Virus and Fermentation. By S. ARLOING (Compt. rend., 103, 1268-1270).-The virus of gangrenous septicemia and of symptomatic anthrax have the power of fermenting nitrogenous substances such as peptone, albumin, and yolk of egg. The products are ammoniacal compounds, with possibly indole and skatole. Hydrogen, nitrogen and carbonic anhydride are evolved, the hydrogen being present in much greater relative proportion in the gases from albumin and yolk of egg than in those from peptone. These facts confirm the analogy between zymotic virus and ferments.

The gaseous infiltration which characterises gangrenous septicemia and symptomatic anthrax is in all probability due to the fermentation of the carbohydrates and nitrogenous compounds in the tissues.

C. H. B.

Loss of Nitrogen by Plants during Germination and Growth. By W. O. ATWATER and E. W. ROCKWOOD (Amer. Chem. J., 8,327-343).-During the germination of seeds, and the early growth of plants, may there be a material loss of nitrogen? (compare Abstr., 1885, 1005). Peas were allowed to germinate and grow for a certain length of time in moist sand, and the nitrogen contained in them and also in the sand and moisture estimated. The sum of these two quantities was always less than the computed nitrogen in the original seeds, the loss varying from 6 to 16 per cent., according to the time