distilling the sausages with fuming nitric acid, a distillate containing indole and skatole was obtained. Ammonia was also present.

Bacteriological investigation showed the presence of two forms of micrococcus, and a bacillus which rapidly liquefied gelatin. This bacillus was alone investigated. Sterilised preparations of blood, liver, lung, heart, and intestine, the materials out of which the sausages are chiefly made, were subjected to its action, the usual precautions against infection from other bacteria being taken. From blood, skatole, indole, and leucine were obtained after it had acted for ten days; from the liver, lung, and heart similarly treated, indole, butyric acid, choline, neuridine, dimethylamine, and trimethylamine were obtained. From the intestine, ammonia, choline, methylamine, dimethylamine, trimethylamine, and diethylamine were obtained. In control experiments in which no special bacillus was employed, but simply putrefaction allowed to take place, the same substances were formed, with the exception of diethylamine. As a result of the action of the bacillus on a nutritive medium, consisting of meat infusion to which peptone was added, trimethylamine, diethylamine, neuridine, and triethylamine were formed. In all the preceding cases, the bases obtained were injected into animals (guinea-pigs and rabbits), and in all cases with a negative result. If this bacillus is the cause of the formation of a poisonous base, it is necessary to investigate its action at different stages, for in the later stages of its action it seems to act destructively on the bases formed, or it may be here again that the methods adopted to obtain the bases themselves bring about the decomposition of the poison into the simpler non-poisonous compounds above mentioned. W. D. H.

Chemistry of Vegetable Physiology and Agriculture.

Chemical Constituents of Bacteria. By L. VINCENZI (Zeit. physiol. Chem., 11, 181-183).-The experiments relate to Bacillus subtilis. A pure culture was obtained by Roberts' (Phil. Trans., 164) method. The fluid containing them was filtered through asbestos, the bacteria remaining on the filter were washed with water and 0.5 per cent. sodium hydroxide solution, digested with artificial gastric juice for 24 hours, washed free from peptones; finally they were washed with alcohol and ether, and dried.

In the cell-wall, which was all that remained after this treatment, no cellulose was found; but it was nitrogenous, yielding from 5.3 to 11.15 per cent. of nitrogen in different specimens, the amount seeming to depend on the different stages of growth of the bacteria. No opinion is expressed as to the nature of this nitrogenous substance.

W. D. H. Behaviour of Micro-organisms in Artificial Mineral Waters. By J. SOHNKE (Chem. Centr., 1886, 699).-The author corroborates

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previous observations as to the effect of carbonic anhydride on the micro-organisms present in water. Water thus impregnated suffers a constant diminution in the number of organisms possessing vitality. In spring water containing a number of organisms he found that from one-half to two-thirds were rendered inert, or incapable of reproduction, after the water had been impregnated with carbonic anhydride. J. P. L.

Source of Trimethylamine in Ergot of Rye. By L. BRIEGER (Zeit. physiol. Chem., 11, 184-185).-The presence of choline bases in Secale cornutum suggested that it might be the source of the trimethylamine found by Walz. The base obtained is undoubtedly choline; crystals of its aurochloride were obtained; these were prismatic, the prisms often grouped in stars. They contained 44.57 per cent. of gold (theory 44:45). This salt is decomposed at 264 (uncorr.). With platinum chloride, the platinochloride was also obtained. After removing the choline from the alcoholic extract of Secale cornutum by precipitation with alcoholic mercuric chloride and filtering, not a trace of trimethylamine was obtained by distilling the filtrate, so showing that it is under ordinary circumstances a decomposition product of choline. W. D. H.

Amount of Caffeïne in Various Kinds of Coffee. Bv B. H. PAUL and A. J. COWNLEY (Pharm. J. Trans. [3], 17, 565).-In estimating caffeïne in coffee beans, the best results have been obtained by the following method. The finely powdered coffee is mixed with moist lime, and percolated with alcohol. The residue left on evaporating the percolate is treated with water and a few drops of dilute sulphuric acid, filtered, and the filtrate exhausted with chloroform, which on evaporation leaves the caffeïne fit for weighing. By this method, the following results have been obtained with different kinds of unroasted coffee ::

Roasted coffee contains about 13 per cent. of caffeïne, but this amount varies slightly.

D. A. L.

Ash of Cinchona Bark. By D. HOOPER (Pharm. J. Trans. [3], 17, 545-546).-The average obtained from 300 estimations shows that barks cultivated in India contain over 3 per cent. of ash. Renewed and old natural barks are poorer, but never fall below 2 per cent. of ash. Young bark and branch bark gives as much as 4 per cent., and the leaves as much as 5 and 6 per cent. Natural crown bark, which grows at an altitude of 7000-8000 feet, is richer in ash than natural bark which grows at 5000-6000 feet, and the red is

richer than the ledger growing at 3000-5000 feet. The following analyses are of ashes from the bark grown on the Nilgiris, C. officinalis in the Dodabetta plantation, C. succirubra at a lower level at Naduvatam. The figures agree on the whole with those of Carles for American barks, except that no copper has been detected.

Action of Mercurial Vapour on Leaves. By V. JODIN (Ann. Agronom., 12, 563-580).-The author has studied especially the influence of mercurialisation on respiration, and on the power of resistance to desiccation. Simple exposure of the leaf to an atmosphere which is in contact with a surface of mercury or of an amalgamated plate, is sufficient to excite the phenomena of mercurial poisoning. These are an increase at first in the respiratory power, due to a sort of stimulation, perhaps similar to that produced by electricity; after some time the respiratory power falls below that of a non-mercurialised leaf. As regards transpiration, the effect of mercurial vapour is to destroy in a very short time the resisting power of the leaf to desiccation, so that, for example, a leaf which normally takes 103 hours to lose half the total quantity of water which it is capable of losing by exposure to air, will, after mercurialisation, suffer the same amount of desiccation in 14 hours. A litre of air saturated with mercurial vapour at 20° contains at most 0·00071 gram of the metal, yet this quantity is sufficient to produce in a few hours the complete mercurialisation of 30 grams of fresh leaves. It is difficult to class this phenomenon amongst the chemical or mechanical phenomena hitherto recognised as physiological factors. J. M. H. M.

Direct Absorption of Nitrogen from the Atmosphere by Vegetable Soils. By BERTHELOT (Compt. rend., 104, 205-209).The author has extended his researches (Abstr., 1886, 175, 736) to the case of vegetable soils.

The soils were placed in vessels of glazed earthenware, and in some cases were protected, in others exposed to air and rain, the rain-water being collected and analysed, and the amount of ammonia and nitric acid in the air being also determined. The results show that vegetable soils continually absorb nitrogen from the air, even when they are not supporting vegetation. The amount absorbed is in all cases very much greater than the quantity of nitrogen existing as ammonia or nitrogen

oxides in the air or rain. In fact the rain removes from the soil in the form of soluble nitrates considerably more nitrogen than it brings in the form of ammonia. At the same time, the amount of nitrogen absorbed is far greater in the case of soil exposed to rain than where the soil is protected, probably owing to the greater activity possessed by the nitrogen-absorbing organisms under the former conditions. In the majority of cases, a notable proportion of the absorbed nitrogen is converted into nitrates. C. H. B.

Analytical Chemistry.

Determination of Sulphur in Albuminoïd Substances. By W. KOCHS (Chem. Centr., 1886, 894).-Carius's method always gives low results, since even after heating for three hours at 200° the oxidation of the sulphur is not complete. Liebig's method, on the other hand, gives higher and concordant results. Since, however, albuminoïd substances free from ash are liable to produce too violent an evolution of gas, it is convenient to heat the substance with 10 parts of nitric acid of sp. gr. 14, and evaporate to dryness on the waterbath before fusing with potash and nitre. M. J. S.

Weil's Method for the Volumetric Estimation of Sulphides. By C. FRIEDHEIM (Ber., 20, 59-62). The author states that this method is utterly untrustworthy, as copper sulphide when precipitated by hydrogen sulphide from ammoniacal copper solutions carries down copper oxide, and the copper sulphide has a great tendency to oxidise and redissolve. Under these circumstances, a correct result can only be obtained when the error in the one direction chances to equal that in the other. A. J. G.

Volumetric Estimation of Nitrous Acid. By A. G. GREEN and F. EVERSHED (J. Soc. Chem. Ind., 5, 633-634).-In a previous communication (Abstr., 1884, 870), Green and Rideal described a process for the volumetric estimation of nitrous acid by means of aniline. Although the results obtained by this process are very accurate, it is somewhat lengthy, and requires too much care in manipulation to be generally available for technical purposes. In the modification described in the present paper, the authors have greatly simplified and shortened the operation by substituting normal for decinormal solutions. The advantage of this process is that most oxidisable substances which may be simultaneously present are not affected. In fact it is possible to estimate nitrites by this means under conditions which would entirely preclude an oxidation method. D. B.

Determination of Phosphorus in Steel and Iron. By C. MEINEKE (Chem. Centr., 1886, 682).—By precipitating with molybdate

solution at not too high a temperature, the percentage of phosphorus in the ignited precipitate may be taken as 1.754. At higher temperatures the percentage is smaller, but can never exceed the above. There is no necessity to remove silica when determining phosphorus by this method in siliciferous iron. M. J. S.

Determination of Phosphoric Acid. By F. BENTE (Chem. Centr., 1886, 948).-On the occasion of a phosphoric acid determination, in which the precipitates with molybdate and magnesia respectively were allowed only 3 or 4 hours to form instead of 12, as was formerly the practice, low results were obtained. As no other cause for the deficiency could be assigned, the author thinks that the modern practice requires reconsideration.

M. J. S.

Detection of Arsenic. By H. HAGER (Chem. Centr., 1886, 680681). The liquid to be tested is brought in contact with a plate of brass, when the presence of arsenic will be indicated by a grey deposit. Heavy metals, even iron, must be absent. Pure hydrochloric acid should be added until the liquid contains 5-15 per cent. of hydrogen chloride. If much arsenic is present, it is sufficient to put a few drops of the liquid on the brass plate and warm gently. After a minute or two the plate may be rinsed with water and examined. For minute traces, it is better to leave the drops on the plate in the cold, and examine from time to time without rinsing off. One part of arsenic in 80,000 will give a grey film in half an hour, 1 in 250,000 in an hour. If 14 hours elapse without any indication, arsenic may be considered to be absent.

If antimony is suspected, it is better to immerse a strip of brass in the liquid, and either warm (50—99°) or set aside for some hours at ordinary temperature. Arsenic gives a steel-grey to black film, antimony a light-grey. Held in a spirit lamp flame, an arsenic film becomes steel-blue and volatilises; antimony remains unchanged. If the deposit can be scraped off into a dry test-tube, add to it two drops. of water, then 10 of nitric acid (30 per cent.). Arsenic will dissolve, antimony remain undissolved.

M. J. S.

Use of Copper containing Arsenic for the Dearsenification of Hydrochloric Acid. Reinsch's Test for Arsenic. By H. HAGER (Chem. Centr., 1886, 772-773).-Copper foil used for the dearsenification of hydrochloric acid must be pure and its surface bright and free from dirt. Copper foil which has been already used for this purpose, may be scoured with sand to remove the film of arsenic, and again used. The fact that the copper usually contains traces of arsenic does not interfere with its use for the dearsenification of hydrochloric acid, since the arsenic exists in the form of an alloy which is not attacked by acid.

Before using copper foil for the qualitative detection of arsenic by Reinsch's method, it should be tested as follows:-A piece of perfectly bright foil is immersed in perfectly pure hydrochloric acid of 10 to 12.5 per cent., and allowed to remain for two hours; if at the end of that time it is still quite bright, it may be used for the detection of