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been taken up by Winkler, who reaches a con- Dr. Curtius in 1877, appears to possess such an trary result, finding that the action of cobalt and intense affinity for water that its isolation in any nickel on a neutral sodium chlor-aurate solution considerable quantity appears almost impractiis simple, with no secondary reactions, and thinks cable; for in all the reactions yet known in that Krüss and Schmidt must have used impure which it is liberated, water is also of necessity a metals. Dr. Fleitmann has also treated various secondary product, and combines with the amisamples of commercial nickel and cobalt oxides dogen at the moment of its liberation, forming in the manner indicated by Krüss and Schmidt the hydrate. It attacks glass energetically, and with negative results in every case. The
authors rapidly destroys cork or caoutchouc. "It is themselves have in the mean time continued strongly alkaline, tastes somewhat like ammonia, their research and found their conclusions con- and leaves a burning sensation on the tongue. firmed.
It forms well-crystallized salts with most acids, Experiments by R. G. Grissom and B. Thorp which are extremely poisonous, and fatal to the show that lead has considerable facility for form- lower animals. It is an extremely strong reducing double compounds with the halogens and ing agent, precipitating the most easily reducible other analogous radicals and in some cases there metals from solutions
of their salts in the cold. are series of such salts with various ratios be- From these and its other qualities it appears to tween the halogens, all of which are stable and be one of the most remarkable liquids yet discrystallize nicely. Among the halogen com- covered, and likely to be of great use in chemipounds of lead obtained by these authors are lead cal operations. chlorosulpho-cyanide (Grissom), lead bromosul Methyl hydrazine, the simplest derivative of pho-cyanide, lead iodosulpho-cyanide (Thorp), hydrazine or amidogen, isolated by Dr. Gustav lead chloro-cyanide, lead bromiodide (Thorp), and von Brüning, at Wurzburg, is a clear and very lead chloro-bromide (Thorp).
mobile liquid, boiling at 87° C., and possessing a A new acid of tin has been obtained by Prof. most violent affinity for water, in which it reSpring. consisting of two molecnles of a higher sembles the recently isolated hydrazine itself
. oxide, Sn0s, combined with one of water. By Its odor is very similar to that of methylamine, its formula, H.Sn,05, or 25n03.H,0., it appears and the vapor, absorbing moisture and forming analogous to disulphuric acid, H2S,C,07, and di- minute drops of the liquid hydrate, produces a chromic acid, H,Cr,0,. The analyses prove that white cloud in the air. Brought in contact with the tin is present in the form of a trioxide, and water, it instantly dissolves with evolution of that at 100° C., one molecule of water remains great heat. Its hygroscopic character is so procombined with it.
nounced that it attacks the skin in the most A new alkaloid called Imperialine has been iso- painful manner, and rapidly destroys corks or lated by Dr. Fragner, of Prague, from the poi- caoutchouc stoppers. sonous plant Fritillaria imperialis, or Crown Im A new substance, singular alike in its chemical perial. It is obtained from the bulb in the form nature and its properties, has been derived by M. of a yellow precipitate, from the alcoholic solu- Péchard from oxalic and molybdic acids, and is tion of which it crystallizes in short needles that called by him oxalomolybdic acid. It is a solid, become colorless after several recrystallizations, crystallizing in large monoclinic prisms, and and have a composition pointing to the formula, forms a well-defined series of salts. It is nearCH 0N04. The crystals are sparingly soluble ly insoluble in strong nitric acid, but the crysin water, but readily in ether, chloroform, and tals dissolve in cold water, more rapidly on alcohol, and melt at 254° C. A chloride has warming, yielding a colorless and strongly acid been obtained which makes bitter solutions with liquid. That it is a true mixed acid is shown alcohol and water, and forms salts with platinum by the fact that it forms crystalline salts with and gold.
metals. The crystals, when dry, may be preSeveral new fluorine compounds of vanadium served unchanged, either in sunshine or in the have been prepared by Dr. Emil Petersen. Those dark. But if moist, they quickly become colheretofore known containing fluorine and vana- ored blue when exposed to the sun's rays. If dium were oxy-compounds. The most important characters be written on paper with the solution, of the new substances is fluoride of vanadium they remain invisible in a weak light; but, when itself, V,Fe, which has been obtained in fine exposed to sunshine, they rapidly become visilarge rhombohedrons of a dark-green color, and ble, and turn deep indigo. It is curious that is very soluble in water. Other compounds are this effect only happens when the solution is two probably isomorphous fluorides of vanadium spread over paper or other surfaces, for the soluwith potassium and with ammonium; another tion itself may be kept unaltered in the bottle compound with ammonium fluoride which is iso- for any length of time, except for a trace of blue morphous with the analagous chromium and tita- at the edge of the meniscus, when, by surface acnium compounds, while the isomorphous group tion, a little is spread against the interior glass has been completed by the preparation of the walls. If a sheet of paper is immersed in a sataluminum compound; and another pair of iso- urated solution of the acid, dried in the dark, morphous double salts with cobalt and nickel. and then exposed behind an ordinary photoA number of oxy-fluorides, derived from vanadic graphic negative, a very sharp print in blue anhydride, V,0s, and analogous to the oxychlo- may be obtained by exposure to sunlight for rides of phosphorus, have also been obtained in about ten minutes. The color instantly disapcombination with alkaline fluorides.
pears in contact with water, so that if a piece Hydrate of amidogen, or hydrazine, which has of this sensitized paper be wholly exposed to been prepared by Drs. Curtius and Jay, of Er- sunlight, one may write in white upon the blue langen, possesses some very remarkable proper- ground by using a pen dipped in water. If, ties. Gaseous amidogen, which was isolated by however, the paper with its blue markings be
exposed to a gentle heat for a few minutes, the blue changes to black, and the characters are then no longer destroyed by water. A new series of double oxalates of rhodium and the metals of the alkalies and alkaline earths have been described by M. Leidié. The hydrate of rhodium sesquioxide, a substance having the peculiar appearance of a black jelly, which is but slightly attacked by most acids, dissolves readily, when recently precipitated, in a concentrated solution of oxalic acid. On evaporation of this solution, containing presumably rhodium oxalate, no crystalline oxalate is obtained, but only a noncrystallizable transparent mass. If, however, the .. is evaporated along with a solution of neutral oxalate of potassium, sodium, or ammonium, on cooling beautiful garnet-red crystals of a double oxalate are deposited, containing one molecule of the oxalate of rhodium sesquioxide and three molecules of the alkaline oxalate. These salts are analogous to the double oxalates of ferric iron and chromium; but the two series, owing to difference in the water of crystallization, are not isomorphous. Evidence of similarity between iron and rhodium is shown by the fact that their most stable chlorides are those derived from the sesquioxides; but the formation of these double oxalates indicates that the connection is perhaps closer than has hitherto been supposed. And the interest in this connection is not lessened by the fact that iron and rhodium occupy corresponding positions in the eighth vertical group of Prof. Mendeleeff's periic classification. Finding that the compounds existing in zincic hydrate have not been definitely determined, A. M. Comey and C. L. Jackson have begun the investigation of the subject with the o of the sodic zincates. They can be prepared by the action of sodic hydrate on metallic zinc, zincic oxide, or zincic hydrate, and the product seems to be the same in every case. A fusible and an infusible sodic zincate are obtained. The fusible salt is the principal product of the reaction, and forms more than ninety per cent. of the whole. As precipitated by alcohol from its solution in o sodic hydrate, it forms a white mass, made of radiating crystals, often of considerable size, and fuses at about 70° C. The infusible salt crystallizes from the alcoholic washings obtained in the preparation of the fusible compound, and is formed in comparatively small o not constituting, |. Inore than a few per cent. of the whole product. It crystallizes in white needles, sometimes more than a centimetre long, which form loose radiating groups, usually of a conical shape, but occasionally circular or spherical. A new compound, containing aluminum in a lower state of oxidation corresponding to ferrous iron, has been obtained by Prof. Hampe-Clausthal. It is a double fluoride of aluminum and sodium, and was produced by fusing cryolite, the natural fluoride of sodium and aluminic aluminum, along with metallic aluminum. Some interesting new silicon compounds have been described by Prof. Emerson Reynolds. Silico tetraphenylamide (Si(NHC, Hs),) is the first well-defined compound in which silicon is exclusively united with the nitrogen of amidic groups, and is formed by the action of excess of
phenyl-amine on silicon tetrabromide. It is crystallized from carbon disulphide in fine colorless transparent prisms, that melt at 132°C. Other compounds are obtained by the action of silicon tetrabromide on the primary thiocarbamide and some of its derivatives—allyl, phenyl, and diphenyl-thiocarbamides. A new photographic developer, “Eikonogen,” is described by Prof. Liveing as appearing to give greater detail than most of the developers now in use. The tone of the negative is also excellent. Eikonogen is the sodium salt of amido A naphthol-3-sulphonic acid. A series of new aromatic compounds of bismuth have been prepared by Drs. Michaelis and Marquardt. The first member of the series, bismuth triphenyl, is a solid crystallizing in two distinct forms of the monoclinic system. It is obtained by heating the sodium-bismuth alloy with brom-benzene. Other members of the series are bismuth tritolyl, and bismuth trixylyl. Both form good crystals, but no dimorphism was observed. Both compounds by direct addition take up two atoms of chlorine or bromine, with production of compounds in which bismuth assumes its full pentad atomicity, supplying in this way additional proof of the similarity of bismuth to antimony, arsenic, phosphorus and nitrogen. A carbohydrate of the empirical composition CaFi 100s, possessing properties closely resembling those of the arabin of gum arabic has been artifically prepared by Prof. Ballo, of Buda. Pesth. It was discovered, in the course of an attempt to reproduce the conditions under which the acids of the vegetable world are reduced to chlorophyl as a result of the treatment of ferrous sulphate with tartaric acid. “Iso-arabin.” as it is provisionally termed, is an almost colorless syrup, readily mixing with water, does not reduce Fehling's solution, but rotates the plane of polarization to the right, and behaves, generally, like the carbohydrates of the (C.H10O.) group. The potassium salt crystallizes in large anhydrous crystals. With it a small quantity of its hydrate is also formed, and separates in crystals from the alcoholic washings of the crude iso-arabin. Two new crystalline compounds of arsenious oxide with sodium bromide and sodium iodide have been prepared by Prof. Rūdorff. They form two additional compounds of an isomorphous group previously discovered by the author. Five members of the group containing potassium and ammonium had been already described; the two new members contain sodium with bromine and iodine. New Processes.—A new method of obtaining gaseous carbon oxysulphide, COS, discovered by M. Armand Gautier, consists in passing dry carbon disulphide vapor through a |. tube of calcined kaolin. The mixture of gases issuing from the tube, which contains 60 per cent. of carbon oxysulphide, is then freed from its other ingredients. After the experiment, crystals of silica sulphide, SiS, are found in the kaolin tube, and in place of the kaolin, crystals of a sulphosilicate of alumina, or a kaolin in which oxygen has been replaced by sulphur. This result ... up the wide prospect of the formation of a whole series of sulpho-silicates in which the oxygen of natural silicates is replaced by sulphur.
M. Maussier has patented a process for obtain- metric determination of silver, mercury, and ing aluminum by the three operations of desili- thallium by means of potassium iodide is founded fication, reduction, and liquation. Desilification on the insolubility of the iodides of those metals is effected by treatment with fluorine (in fluoride in a nitric solution, provided that such solution of calcium) at a high temperature, in the pres- contains no alkaline iodide. The potassium ence of carbon; reduction by incandescent iron iodide employed as a reagent is poured little by and manganese in the presence of carbon; and little into the acid solution until the starch used liquation, which is intended to separate the as an indicator is colored by the iodine. The aluminum from iron and manganese, by causing liberation of the iodine is due to the presence the melted mass to fall into molds of charcoal. of a very large proportion of nitric acid. The A nearly pure aluminum is obtained.
silver or mercury iodide may be collected and The details have only recently been published weighed; or the reagent may preferably be used of the combined Leblanc and 'ammonia alkali as a standard solution, and the volume of the process of Parnell and Simpson, which has been liquid necessary for precipitation measured. worked experimentally in England since 1885. Industrial Chemistry.The effective disIn it, sodium bicarbonate is obtained by treating posal of the immense amount of sulphurous brine and ammonium sulphide with lime-kiln tank-waste which is developed in the ammonia gases, and the resulting ammonium chloride is process for making soda has been a great source reconverted into sulphide by heating with Le- of expense, and has presented a problem which blanc tank-waste.
has only recently been solved. All the sulphur The Weldon-Pechiney alkali process, which is used in making acid for the alkali industry apemployed at Salindres, France, is based upon pears at the end of the process in this waste. the decomposition of moist magnesium oxychlo The process introduced by Chance Brothers, in ride by heat, which gives free chlorine and hy- 1888, seems to obviate the difficulties which have drochloric acid. By it hydrochloric acid may be hitherto been met. It depends upon the decommade to yield more than 80 per cent. of its chlo- position of the waste by carbonic dioxide. The rine free, against 33 per cent. by the Weldon pro- resultant gas is of constant composition, contains cess, and from
40 to 90 per cent. by the Deacon over 30 per cent. of hydrogen sulphide, and is of process. Its effect upon the Leblanc soda indus- suitable strength for burning to sulphur dioxide try depends, according to Mr. Spencer B. New- for the manufacture of sulphuric acid, or for the bury, upon the fact that it may furnish a cheap preparation of sulphur by the “Claus Kiln," in source of chlorine for making bleaching powder. which the hydrogen sulphide is burned with the It is especially applicable in places where mag- necessary amount of air to produce water and nesium chloride is a waste product.
free sulphur. It is possible that this method, Curious experiments in the volatilization of together with the current low price of pyrites, lead oxide and its action on glass were described will turn the tide again in favor of the Leblanc by Mr. J. W. Hogg in the British Association process. Writing in which lead oxide has been used as a In modern burners for smalls in preparing pigment being placed upon a glass plate or plat- sulphuric acid from pyrites, and especially with inum foil, a polished plate of glass is placed over the Spence furnace, it is possible to burn the this as closely as possible, but prevented by suit- pyrites down to 1 per cent. for sulphur. The reable means from actual contact. On heating up sulting, cinders from non-cupreous pyrites conto hardly visible redness, a distinct reverse of sist chiefly of ferric oxide, and are nearly free the design will appear upon the upper glass. The from phosphorus. Such cinders are valuable as quantity of lead oxide that will produce this ef- iron-ore. Cinders containing notable quantities fect is not shown by the most delicate balance. of copper are treated by the wet extraction pro
A good experiment in the resolution of an en- cess. “If much silica and little silver are present, dothermic compound into its elements is de- the cinders are smelted with the addition of raw scribed by T. E. Thorpe. In studying the action pyrites in the form of " fines,” by which a “ matte" of the fluid alloy of potassium and sodium on is obtained of from 50 to 60 per cent. of copper. carbon disulphide, the author obtained a yellow- The iron and silver contained in the cinders are, ish-brown substance that exploded with great however, lost. But if a determined proportion violence when subjected to pressure or friction of silver and little silica are present, the HenIf the explosion took place in contact with car- derson wet process is used for the extraction of bon disulphide, that substance was resolved into copper and silver. At Elizabeth, N. J., and Naits elements. A similar decomposition of carbon trona, Pa., the cinders are roasted with salt. disulphide into carbon and sulphur can readily The resulting cinders are lixiviated with water, be effected by exploding a charge of fulminate and then with the dilute acid obtained in the within a tube containing carbon disulphide vapor. operation; and the silver is precipitated by po
The cocaine extracted from coca-leaves con- tassium iodide or hydrogen sulphide, and the tains a number of other alkaloids from which it copper by scrap iron. must be separated, which have hitherto been re According to Spencer B. Newbury's review garded as of no value. A method has been de- of the “Sulphuric Acid Manufacture” in the vised by C. Liebermann and F. Giesel for con- “ American Chemical Journal," chamber acid has verting them, by boiling with hydrochloric acid, generally a strength not over 50° B., correspondinto ecgonine; this into the benzoyl derivative; ing to about 62 per cent. of H.S04. This is and the benzoyl ecgonine into methyl-benzoyle- strong enough for the manufacture of superecgonine, or cocaine. Thus the whole product phosphates, ammonium sulphate, and the saltof the extraction process is converted into the cake process. Acid of greater strength is need valuable cocaine.
ed for refining petroleum and making nitric acid Adolphe Carnot's new process for the volu- and nitro-compounds. Acid from the Glover
tower may reach a strength of 62° B., corresponding to 81.7 per cent. of H2SO4. i. this point the concentration must be carried on in platinum stills or glass retorts. Since acid from the Glover tower can not generally be concentrated in platinum, on account of the deposition of ferric sulphate, it is first concentrated in lead pans to 60 B., and then run into the stills. Platinum is liable to corrosion, especially if the acid contains nitro-compounds or considerable quantities of arsenic. |. nitro-compounds may be removed by adding ammonium sulphate, which gives rise to water and free nitrogen. Cast-iron retorts have been successfully used for the final concentration, which may be carried on in them up to 98 per cent. H2SO4. By using glass, acid from the Glover tower may be concentrated directly, without difficulty from the presence of arsenic or nitrogen compounds.
The same writer reviews the present state of the alkali industry in the United States; while a small amount of Leblanc soda was formerly made in this country, the industry is not known to exist here at present. Caustic soda has been made by the cryolite process for many years by the Pennsylvania Salt Manufacturing Company, at Natrona, near Pittsburg. Most of the soda ash used for glass and soap o until recently, imported from England. The manufacture of ammonia soda was begun about 1882 by the Solvay Process Company, at Syracuse, N.Y., and their production amounted. in 1888, to 60,000 tons, or one third of the total quantity consumed in the United States. Caustic soda is also made there on an extensive scale. Dr. Francis Wyatt has urged the adoption of the Leblanc process in this country, as |. suited to our conditions, but the success of the ammonia process at Syracuse shows that that also can be made profitable here.
The application of a cheap method of recovering the ... of the salt treated by the ammonia-soda process, which is now lost as calcium chloride, and making it available for bleaching, etc., would contribute greatly to assuring the supremacy of that method. Many attempts to accomplish this have been made, but as yet no commercially successful process has been made public. Among the methods that have been experimented upon are the decomposition of calcium chloride by means of silica and clay at a high temperature (Solvay); the decomposition of ammonium chloride into ammonia ...] hydrochloric acid (Mond): the conversion of calcium chloride by the addition of lime into the oxychloride and the decomposition of this by heating in a current of air; and Mond's method of obtaining ammonia and chlorine from ammonium chloride, which is called by Spencer B. Newbury practically an application of the Weldon-Pechiney to the ammonia process. Ammonium-chloride vapor is passed over heated magnesia, to which 5 or 10 per cent. of sodium or potassium chloride has been added. Ammonia and steam are produced, and magnesium chloride remains. he latter is then decomposed by heating intensely in a current of air: chlorine is given off and magnesium oxide is left behind to be again treated with ammonium chloride. The commercial practicability of this process has not been reported upon.
vol. xxix.-9 A
In Dr. Netto's process, which is at work on the Tyne, for manufacturing aluminum from cryolite, the cryolite is first fused with salt in a reverbatory furnace; then run out into converters in which sodium is gradually added. Sodium fluoride and metallic aluminum are formed. The sodium is obtained by allowing molten caustic soda to flow gradually on to charcoal contained in a cast-iron retort heated to dull redness. The sodium carbonate formed in the reaction sinks to the bottom of the retort. The greater concentration of the caustic soda thus produced enables the temperature to be kept lower than in the Castner process. Analytical Chemistry.—A new method of chemical analysis, in which capillary attraction Wo an important o is described by Charles . Phillips. One of its peculiar advantages, as resented by the author, is that experiments can filed away for future reference, and in medicolegal investigations the actual evidence can be carried into court and filed away with other legal documents. Test papers are prepared by dipping, chemically pure, white filtering papers, having a close grain, severally, into solutions of ferrocyanide of potassium, neutral chromate of potas. sium, bromide of potassium, and hyposulphite of sodium. The solution to be ... is dropped from a tube upon one of these papers, and the reaction compared with a set of sample standard reactions of the various elements and compounds, with which the analyst should already have provided himself. The author has tested and describes in his paper the reactions of all the important metals of the 6 groups, with 4 reagents, making in all 116 reactions. In testing for sulphur according to Schönn's method, by heating an organic substance with a metal (sodium), dissolving the sulphide formed in water, and adding a solution of sodium, nitroprusside, Charles W. Marsh found powdered zinc a more convenient substance for decomposing organic bodies, and at the same time uniting with the halogens to form chloride, bromide, or iodide, as the case might be—all substances soluble in water. From the water solution the corresponding silver salt could be precipitated, and that would aid in identifying the halogen in the substance treated. In substances containing sulhur, zinc sulphide would be formed, and could e determined by convenient tests. The method of procedure thus outlined was tried on many organic substances containing chlorine, bromine, iodine, and sulphur, and gave the expected results. It is claimed that, by using this process. the substances in question can be accurately and rapidly detected in organic compounds by the use of apparatus and chemicals ordinarily found in chemical laboratories. Analyses by Ira Remsen and W. M. Burton indicate that the substance known commercially as saccharin is a mixture of para-sulphaminebenzoic acid, benzoic sulphinide, and acid potassium o-sulpho-benzoate, and that the amount of the sulphinide present is somewhat less than 50 per cent. The sulphinide is the only constituent of commercial value, and is rated as having about 300 times the sweetening power of cane sugar. It follows that commercial sac. charin. instead of being “300 times as sweet as sugar,” is not more, and is probably considerably less, than 150 times “as sweet as sugar.” It would, the authors think, be nearer the truth to say that commercial saccharin has a sweetening power about 125 times as great as that of cane Sugar. Oxamining 36 samples of wine, obtained in the local market, for adulterations, C. A. Crampton found a distinct test for boracic acid in all but two of them, while it did not appear probable that that substance had been introduced to all of them for purposes of preservation. Baumert, who had made the same observation in some California wines, knowing that some California soils contained borax, supposed that the lants had derived this constituent from the soil. ut the test was also obtained by the author in wines from New York, Ohio, o, Carolina, and Virginia. Prof. Rising, of California, suggested that boracic acid was a normal constituent of grape juice, at least in California. Soltsien concluded, from other analyses, that it was not an unusual constituent of wine ash. Ripper found it as a normal constituent of 1,000 samples of German and foreign wines, and of various parts of different grape stocks. Baumert has since found it in every case. Mr. Crampton has applied the test to other plants than the vine, and has found boracic acid in some, as in the peach and watermelon, but not in all, whence he concludes that it occurs more generally in plants than has been supposed, but not universally. It has been observed by Edgar F. Smith and Lee K. Frankel that mercury can be electrolytically separated without difficulty from solutions containing a large excess of an alkaline cyanide, and with comparatively weak currents. With copper solutions the metal would not separate until the alkaline cyanide had completely disappeared, and the presence of copper generally, in solutions containing both metals, exercised a considerable retarding influence upon the precipitation of the mercury. It was ascertained that the cyanide method is not applicable to the separation of silver and copper. A method is described by Leo Vijnon for the volumetric determination of carbonic acid in water, whether free or in a state of semi-combination, by means of a standard solution of calcium hydroxide, with phenophthalein as an indicator. It depends upon the action of the acid in decolorizing the red liquid which is formed when certain proportions of lime-water and the saturated alcoholic solution of phenophthalein are mixed. Samuel C. Hooker has employed the green coloration given to the sulphuric-acid solution of carbazol by adding nitric acid as the basis of a process for the estimation of nitrates in natural waters. The extraordinary delicacy of the reaction renders it particularly suitable for the purposes of water analysis, and makes it possible to determine a quantity of nitric acid containing as little as Town of a milligram. It is not, however, peculiar to nitric acid, but appears in contact with all oxidizing agents. Of these, however, nitrous acid and ferric iron are the only ones likely to be found in natural waters in appreciable quantities, and are, therefore, the only ones requiring special attention. The Kjeldahl process has been successfully applied by Messrs. }. and Martin to the deter
mination of the total organic nitrogen existing in waters. From their experiments the authors conclude that the nitrates and nitrites do not interfere with the accurate determination of the organic nitrogen. The error which might otherwise be caused disappears under the conditions of great dilution which exists in natural waters. A report is given by Dr. T. M. Brown and Henry Martin of experiments in the determination by the Kjeldahl method of the organic nitrogen in a large number of natural waters of Massachusetts during the three successive months of June, July, and August, 1888. It is noted that the organic nitrogen in the surface waters exof is in general about double the albumenoid ammonia. In the ground waters the relation of the albumenoid ammonia is still less. But too much importance must not be given to this relation in the latter case, because, from all the sources of error not having been known at the time, the figures soon for the organic nitrogen are a little too high. The peculiar feature of Dr. Bennett F. Davenport's modification of Wanklyn's method of milk analysis is the use of an evaporating capsule (of o of such relatively large area as will eave the residue thin enough to be readily exhausted of its fat in the subsequent treatment with boiling petroleum naphtha. The curvature of the capsule is also adjusted so as to correspond with that which the milk assumes when drawn up the rim by capillarity, whereby a uniform thickness of deposit is assured. The process is expedited by using a closed water-bath. Satisfactory experiments in the determination of carbonic acid and moisture in the air by gravimetric methods are described by J. S. Haldane and M. S. Pembrey. The methods are not new in general principle, but by attention to details which are described in their paper the authors found them exceedingly convenient and much more accurate than the corresponding methods in ordinary use. Mr. W. L. Dudley describes some modifications of the methods of organic analysis by combustion which appear to simplify and facilitate the procedure. The process may be applied with suitable modification to liquids, both to those having high boiling-points and to volatile liquids. A method for the analysis of butter, oleomargarine, and kindred substances, in use by H. N. Morse and W. M. Burton, depends upon the fact that the relative quantities of alkali required to neutralize the soluble and insoluble acids are constant for one fat or oil, but variable for different fats or oils. The authors claim as its advantages, that it is volumetric throughout; that it obviates the necessity of weighing the specimen or fat; and that it readily discriminates between genuine butter and any mixture of cocoanut-oil and other fats or oils. That is, it succeeds at that point where the methods of Hehner and Koettstorfer may fail. Chemical Synthesis.-The artificial synthesis of glucose has been so perfected that the product is now obtained in considerable quantities; and it will also ferment with yeast like natural glucose, and like that substance will }. on reduction with sodium amalgam, the exhydric alcohol mannite. As obtained by the