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thoroughly dried, either in a vacuum or at 100°, also that the ether should contain no water; as otherwise, carbohydrates are dissolved, which materially raise the percentage of fat. Several analyses are given to show the effect of drying. E. W. P.
Relation between Specific Gravity, Fat, and Solids in Milk. By P. VIETH (Analyst, 49-51).-Hehner and Fleischmann have published formula (for the latter see this vol., p. 94) by which the fat in milk can be calculated from the specific gravity and amount of total solids. With Hehner's formula, the difference between the calculated percentage of fat and that determined by extraction from a paper coil (Adams' process) is small with low percentages of fat, but considerable when the percentage of fat is large. Comparing Fleischmann's formula with the results of extraction after drying on gypsum, the differences never exceed 0.2 per cent. (above or below), and the average difference in 530 analyses was 0.02 per cent. These formulæ are only applicable where, as in cow's milk, the ash, proteiïds, and sugar re in the ratio 1 : 5: 6. In human milk the ratio is 1: 5: 10, and in mare's milk, 1 : 6 : 23. M. J. S.
Action of Alcohol on Butter Fat. By C. B. COCHRAN (Analyst, 13, 55-57).—To test artificial butter for added tributyrates, it has been recommended to treat the sample with alcohol, and ascertain by Reichert's process whether the amount of volatile acid in the undissolved residue is less than in the original substance. Genuine butter gives, however, precisely this result. Several samples of genuine butter were treated with alcohol at 23-25°, using 10 c.c. of 90 per cent. alcohol to 1 gram. The percentage of volatile fatty acid in the undissolved residue was in every case reduced, but in no case did the distillate from 2.5 grams of the undissolved portion require less than 9 c.c. of N/10 alkali. This number is therefore accepted as the minimum for a genuine butter, after treatment with the above proportion of alcohol, and it is suggested that adulteration is more likely to be detected by applying Reichert's method to the undissolved fat than by using it on the original butter.
It is noticed that genuine butter which has been kept for some time may in Reichert's process give results falling below the standard of 125 c.c. of N/10 alkali for 25 grams of butter. In one case of a butter 10 months old, but in good preservation and palatable, only 105 c.c. were required. M. J. S.
Bases in Alcoholic Liquids. By L. LINDET (Compt. rend., 106, 280-283).-500-1000 c.c. of the liquid at 50° Gay-Lussac is mixed with 20 grams of strong sulphuric acid, well agitated and distilled until all alcohol and water is expelled. 0.5 gram of mercury is added, and the operation conducted exactly as in the estimation of nitrogen by Kjeldahl's process, the nitrogen of the bases being obtained in the form of ammonia. One part of base in 1,000,000 parts of alcohol can be detected, and the distillate contains no bases.
The examination of several alcoholic liquids in this way shows that the amount of ammonia per litre of liquid varies from 0.40 to
23.05 mgrms. Alcohols obtained by the fermentation of grain contain the smallest amount; the quantity in rum is much higher than in other spirits, whilst the alcohol from beetroot molasses contains a very much higher proportion than any of the others. C. H. B.
Estimation of Morphine in Opium. By A. KREMEL (Chem. Centr., 1887, 1529-1530, from Pharm. Post, 20, 661).-5 grams of opium powder is digested with 75 c.c. of lime water for 12 hours with frequent shaking; 60 c.c. of the filtered liquid, which should not have an alkaline reaction, is mixed with 15 c.c. of ether and 4 c.c. of normal ammonia in a weighed flask. The flask is corked and the contents mixed with gentle shaking. The ether is decanted after remaining at 10-15° for 6 to 8 hours, another 5 c.c. of ether is added, and this again decanted after gentle shaking. The crystals of morphine separated with the ether are collected on a small filter. These crystals, with those remaining in the flask, are washed with 5 c.c. of water, and both finally dried at 100° and weighed.
J. P. L. Estimation of Morphine in Opium. By E. F. TESCHEMACHER and J. D. SMITH (Chem. News, 57, 93-95, 103-105).—The authors review and criticise the methods recommended for the determination of the morphine in opium, and point out that those depending on the use of lime, much alcohol, or much water, are untrustworthy; in this category they include the Squibb-Flückiger method even as modified by Stillwell (Abstr., 1887, 403), the HagerJacobsen, Merck's, the British Pharmacopoeia, and other methods. It is noteworthy that any one of these methods will give concordant results when applied in the saine manner to the same sample of opium, but nevertheless the results are erroneous. A small quantity of alcohol is necessary, as otherwise the morphine is precipitated in a form difficult to wash, but the quantity should not exceed 50 grains of alcohol to 200 grains of opium; the authors approve the idea suggested by Allen, of finally titrating the morphine, as this excludes errors due to adherent colouring matter, &c. Their own method is fully described, and is briefly as follows:-Exhaust 200 grains of opium with warm distilled water, concentrate steadily to a thin syrup, mix with 50 fluid grains of alcohol, sp. gr. about 0-820, and about 600 fluid grains of ether, then add 50 fluid grains of ammonia, sp. gr. 0-935, shake well, and agitate occasionally during the next 18 hours, filter, and to remove colouring matter, &c., wash first with 80 per cent. spirit saturated with morphine, then with morphinated water. Dry carefully, pulverise, digest with benzene, filter, dry, weigh, and finally titrate with standard hydrochloric acid, using litmus as indicator, &c. Benzene dissolves all other opium alkaloïds except morphine and narceïne, and the latter is removed in the earlier stages of this process. D. A. L.
Estimation of Morphine in Opium. By R. WILLIAMS (Chem. News, 57, 134-135).-The author's experience with the processes generally employed for the estimation of morphine in opium confirms the opinion expressed by Teschemacher and Smith (preceding
Abstract). The method he now employs is similar to that described by the latter authors, except that he prefers to extract the opium with cold instead of warm water, and uses 100 instead of 50 grains of alcohol.
D. A. L.
Testing Neutral Quinine Salts. By L. SCHÄFER (Arch. Pharm. , 25, 1041).-The oxalate test may be applied directly to those neutral quinine salts whose solubility in water is not less than that of quinine sulphate, for instance the hydrochloride, bromate, valerate. Thus a molecular quantity corresponding with 1 gram of the sulph. cryst. is weighed off and treated as described in the following Abstract. Collateral alkaloïd mixtures are indicated as sharply as in the case of the sulphates, except that, as with quinine valerate, a portion of the acid is lost during heating and it becomes alkaline, when a little more passes the test.
Estimation of Cinchonidine in Quinine Sulphate. By L. SCHÄFER (Arch. Pharm. , 25, 1033–1041).-The ammonia method given by Kerner and Weller (Abstr., 1887, 1146) is shown to be quite fallacious, mainly owing to the readiness with which a double salt of quinine and cinchonidine sulphate is formed. Further, animal as well as vegetable fibres absorb variable quantities of the quinine alkaloïds, and the use of different kinds of filter-paper may produce a difference of 1 c.c. in the amount of ammonia solution used. Glass-wool filters should be employed. The oxalate test (Abstr., 1887, 623) is slightly modified on this account. 1 gram of quinine sulph. cryst. (0.85 gram completely dried sulphate) is boiled with 35 c.c. water in a small tared flask. To this is added 0.3 gram of neutral crystallised potassium carbonate (oxalate?) in 5 c.c. water, and the solution is made up to 413 c.c. The flask is kept at 20° and shaken occasionally during half an hour, when its contents are filtered through glass-wool, and to 10 c.c. a drop of officinal aqueous soda is added. No turbidity appears for some minutes if the original sulphate is pure. 1 per cent. of cinchonidine may thus be missed. 1 per cent., however, gives an immediate turbidity, and larger quantities afford a precipitate. On filtering through glass-wool after one hour, 2 per cent. or more affords an immediate turbidity or a precipitate. J. T.
Colchicine-like Decomposition Product. By G. BAUMERT (Arch. Pharm. , 25, 911-918).-In a supposed poisoning case, the Stas-Otto method was followed, and a substance closely resembling colchicine was found, although death had occurred twenty-two months previously. Parallel reactions made with pure colchicine differed in many cases from those obtained with the extract from the body; but when an aqueous extract was exhausted as far as possible by means of chloroform, and to this was added pure colchicine, the reactions then became identical with those given by the substance obtained from the body. Brieger, however, found that the substance was a peptone and physiologically inactive. Millon's reaction confirmed this. The peptone is also distinguishable from colchicine by giving a precipitate with picric acid, and with platinum chloride.
General and Physical Chemistry.
Spectrum of the Oxyhydrogen Flame. By G. D. LIVEING and J. DEWAR (Proc. Roy. Soc., 43, 347-348).-The authors examined the third portion of the water spectrum extending into the ultra-violet. The lines fall into rhythmical groups, in which in many cases the distances between the lines measured in wave-lengths are in arithmetical progression. They find a striking resemblance between these groups and the groups A, B, and ∞, but no exact correspondence, as stated by Deslandres. They have found many of the lines predicted by Grünwald (Abstr., 1887, 1070).
H. K. T.
Wave-lengths of two Red Lines in the Spectrum of Potassium. By H. DESLANDRES (Compt. rend., 106, 739).-By means of the electric arc and a Rutherfurd grating on glass, the author has determined the wave-lengths of the two potassium lines in the extreme red, and obtains for the stronger of the two the value 76630, and for the weaker 7696-3, D being taken as 5888.9. The mean value is 7679.65. Mascart by the same method found 7680 0, D being taken as 5888.0.
C. H. B.
Ultra-violet Band-spectrum of Carbon Compounds. By H. DESLANDRES (Compt. rend., 106, 842—846).—The violet portion of the visible spectrum of carbon compounds in tubes under low pressure contains two groups of bands, the first of which is usually attributed to hydrocarbons, and is seen in the spectra of comets, whilst the second is most distinct under very low pressures, and was attributed by Ampère to carbonic oxide.
Carbonic oxide with a non-condensed spark under atmospheric pressure shows the first group only, whilst in the ultra-violet there is a faint trace of the carbon line 12478.5. Under very low pressures, however, this gas gives a very fine band spectrum in the ultra-violet, whilst in the visible spectrum group 1 is replaced by group 2, which is very brilliant. The ultra-violet spectrum includes, besides some bands of group 1, at least two distinct groups of bands, different in character from the visible bands, and readily distinguishable from one another. The bands in the 3rd group shade off on the more refrangible side, whilst those of the 4th group shade off in the opposite direction. Almost exactly the same spectra were obtained at low pressures with carbonic anhydride, acetylene, and cyanogen, although in the latter case the special bands of nitrogen and of cyanogen were recognisable. The exact origin of the bands was not determined. Their appearance is independent of the presence of nitrogen, and it seems probable that group 3 is due to some oxygen compound, whi'st group 4 is due to the vapour of carbon only. The bands on the one hand and the lines on the other may be divided into series which, 2 u
when represented on a scale of vibration-frequency, are in arithmetical progression, and are represented by the expression Am2 + a, m being a whole number.
Group 3 has the same general appearance as group 2, usually attributed to carbonic oxide. The arrangement of the bands is simple, but the bands themselves are of complex structure.
Group 4 is different in appearance from any other carbon groups or nitrogen groups. It resembles the absorption-spectrum of iodine, and can be divided into five similar series, which are also in arithmetical progression. The bands are of comparatively simple structure, and are resolved into lines by two prisms of Iceland spar. band consists of two equal arithmetical series which are superposed on each other.
The division of the bands into series requires three successive operations, and the whole of the rays may be represented by a function of three parameters, m2, n2, p2, of the form
f(n2, p2) × m2 + Bn2 + $(p2),
m, n, and p being whole numbers. The law of periods in the more general vibratory motion of a solid, and in all similar problems of periodic vibrations, can likewise be represented as a function of three parameters, m2, n2, and p2, which correspond with the three dimensions of space. The functions f and have not been accurately determined, but they seem to be of simple character, such as squares, inverse squares, or square roots. C. H. B.
Spectra of Meteorites. By J. N. LOCKYER (Proc. Roy. Soc., 43, 117-156). Observations were made on the spectra of elements and meteorites at low temperatures, namely, those of the bunsen flame, oxyhydrogen blowpipe, and vacuum discharge. The spectra were compared with those of the heavenly bodies. The following deductions are made:-The luminous phenomena of all heavenly bodies shining by their own light, with the exception of stars like the sun and Sirius, are produced by meteorites; the temperature of the meteorites in some cases is about that of the oxyhydrogen flame; the intensity of the light depends on the number of meteorites in the swarm; the main factor in the spectra produced is the ratio between the meteorites and the spaces between them; when the space is great the tenuity of the gases given off by the collisions is too great to give a luminous spectrum, later bright lines or flutings are produced, finally when the meteorites themselves are more crowded, and at a higher temperature, a continuous spectrum with dark lines will result; new stars are produced by the collision of swarms of meteorites, the lines being those of elements which give bright lines at low temperatures; the hydrogen spectrum in nebulæ is due to electrical excitation, the glow of a meteorite in a vacuum giving the hydrogen or carbon spectrum according to the amount of heat applied; the production of iron meteorites with embedded stones is due to the welding of the fused iron when meteorites collide. The author represents the consecutive conditions of stars by a curve, commencing with a low temperature swarm of meteorites, which by their gravitation produce a rise of temperature up