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These precious remains, the skull, tooth, and femur, are described by Dr. Dubois, with full details, and for these the anatoinical reader will look to the memoir itself. The conclusions drawn by the author from these fossils are so comprehensive, that they will be carefully weighed by antlıropologists of every nation. It is only justice to Dr. Dubois and his admirable memoir to say here, that he has proved to science the existence of a new prehistoric anthropoid form, not human indeed, but in size, brain power, and erect posture, much nearer man than any animal hitherto discovered, living or extinct.

The brief review here given of the main facts relating to this discovery, together with the figures reproduced from the memoir, will afford the reader some idea of the importance of this latest addition to the known allies of primæval man, if not to his direct ancestry. Whatever light future researches inay throw upon the affinities of this new form that left its remains in the volcanic deposits of Java during later Tertiary time, there can be no doubt that the discovery itself is an event equal in interest to that of the Neanderthal skull.

The man of the Neander valley remained without honor, even in his own country, for more than a quarter of a century, and was still doubted and reviled when his kinsmen, the men of Spy, came to his defense, and a new chapter was added to the early history of the human race. The ape-man of Java comes to light at a more fortunate time, when zeal for exploraţion is so great that the discovery of additional remains may be expected at no distant day. That still other intermediate forms will eventually be brought to light no one familiar with the subject can doubt. Nearly twenty years ago, the writer of the present review placed on record his belief that such missing links existed, and should be looked for in the caves and later Tertiary of Africa, which he then regarded as the most promising field for exploration in the Old World. The first announcement, however, has come from the East, where large anthropoid apes also survive, and where their ancestors were doubtless entombed under circumstances favorable to early discovery. The tropical regions of both Asia and Africa still offer most inviting fields to ambitious explorers.

Yale University, New Haven, Conn., January 21, 1895.

SCIENTIFIC INTELLIGENCE.

I. CHEMISTRY AND Physics.

CHEMICAL ABSTRACTS. 1. On a new mode of preparing Hydrogen phosphide.—The supposition that phosphorus does not combine with hydrogen directly, sounded on the early experiments of Fourcroy and Vanquelin, has been shown by RETGERS to be erroneous. After he had established the great readiness with which arsenic unites with moderately heated hydrogen, be inferred that ordinary phosphorus would also combine with this gas, were it not for its low fusing point, 44°. He was led, therefore, to use red phosphorus, whose melting point is much higher. And he found that when dry hydrogen is passed over red phosphorus contained in a glass tube, at a gentle heat, direct combination readily takes place and the issuing gas inflames spontaneously in the air. Evidently the non-spontaneously-inflammable gaseous phosphide of hydrogen must contain a certain amount of spontaneously-inflammable liquid phosphide; and by conducting, the evolved product through a U. tube placed in a freezing mixture, this latter phosphide was obtained separately. In addition, the solid phosphide is also produced and is deposited as a yellow mass just beyond the heated portion of the tube. On removing the source of heat, the evolved gas soon ceases to take fire on contact with the air and is almost pure hydrogen. The author thinks this process much preferable to the older methods of preparing hydrogen phosphide, not only because of the ease with wbich it may be operated, but also because it affords an excellent example of the formation of the three hydrogen phosphides by direct synthesis.-Zeitschr. anorg. Chem., vii, 265, September, 1894.

G. F. B. 2. Ona Hydrate of Sodium Trioxide.-By the action of ordinary alcohol upon sodium peroxide, TAFEL bas obtained a new substance of rather remarkable composition. When the alcohol is poured on the peroxide, a part of the latter enters into combination to form a strongly alkaline solution, while the rest, about equal to this in amount, changes its color from pale yellow to pure white and becomes a fine granular powder, totally unlike the peroxide in appearance. It is soluble in water, but with much less rise of temperature. While the peroxide is stable even at high temperatures evolving no oxygen below redness, the new substance evolves oxygen copiously on simple warming; and if heated rapidly in a test tube explodes violently with the production of flame. If tbe dry powder be touched with a heated rod, the escaping oxygen sets the particles into a rapid whirling motion, with a very considerable rise of temperature; the action extending throughout the entire mass, pure dry oxygen being continuously evolved. On heating still more strongly, the residue melts and evolves vapor of water, leaving ordinary sodium bydrate. On analysis it afforded

the composition H Na 0,, being formed according to the equation :

Na,, + C,H,OH=C,H,ONa+ HNO, The author regards the new substance as the hydrate of sodium trioxide, Na,0,; and therefore gives it a doubled formula, H, Na, 0. In ice-cold water it dissolves unchanged, but at higher temperatures the solution slowly evolves oxygen. If alcohol be present, the evolution of gas increases and the solution deposits crystals of the hydrate of sodium peroxide Na,,(H,O),, discovered by Vernon Harcourt. By bydrogen chloride, it is converted into sodium chloride, hydrogen peroxide and oxygen gas. In preparing this new substance, the author finds 12 grams sodium peroxide and 200 c.c. of ice-cold absolute alcohol, convenient quantities to employ. After shaking them well together, the liquid is filtered off, and the white sandy product-separated from any undecomposed peroxide—is washed with cold alcohol and ether and placed in a desiccator. — Ber. Berl. Chem. Ges., xxvii, 2297, September, 1894.

G. F. B. 3. On a pure white Stannic sulphide.A new form of tin disulphide has been prepared by Schmidt wbich is pure white in color and which is readily soluble in ammonium carbonate. To prepare it, metallic tin is dissolved in hydrochloric acid, and the stannous chloride is converted into stannic chloride by means of nitric acid ; the excess of acid being removed by evaporation. After dilution, the tin sulphide is thrown down by hydrogen sulphide in the ordinary yellow form. It is washed, separated from traces of arsenic by solution in hydrogen chloride and reprecipitation, and digested with ammonium hydrate in excess for some days. The clear solution is neutralized with dilute sulphuric acid, when an almost pure white precipitate is obtained. On dissolving this in ammonium carbonate and neutralizing with sulphuric acid the precipitate is pure white. It is very bulky and is in a different state of hydration or of molecular aggregation from ordinary stannic sulphide. Upon drying it becomes amber-yellow and is no longer soluble in ammonium carbonate.--Nature, li, 85, November 1894.

G. F. B. 4. On the Properties of Liquid Ethune and Propane.—The properties of the gaseous hydrocarbons ethane and propane in the liquefied condition have been studied by HAINLEN in Lothar Meyer's laboratory. The propane was obtained pure by the process of Köhnlein which consists in heating propyl iodide to 130° in a sealed tube with aluminum chloride. After twenty hours, the tube was allowed to cool and was afterwards placed in a freezing mixture; it could then be opened without danger and the gas be transferred to a gas-holder. It was condensed to a liquid in a U-tube surrounded with solid carbon dioxide, and then was distilled over into a special boiling point apparatus, which consisted of a glass tube closed at the lower end, baving a side lube by which the gas entered, and provided at top with a stopper through which a thermometer and the exit tube passed. Solid carbon dioxide surrounded the upper half of this tube and a layer

of felt the lower half; the propane condensing above and collecting below. By removing the felt the liquid boiled, at first irregularly ; but it finally became steady and the corrected temperature-reading was found to be -37o at 760m. The vapor pressures at different temperatures from – 33° to +12.5° were determined by placing the liquid propane in one leg of a U-tube and air in the other; the two being separated by mercury and the pressure estimated from the compression of the air. From 12.5° to 102° the pressure was measured in a Cailletet apparatus. It was found that at -33°, the pressure was 1:8 atmospheres; at – 19°, 2.7; at —15°, 3:1; at -11°, 3:6; at -5°, 4:1; at -2°, 4:8; at +1°, 5:1; at 5.5°, 5:9; at 12.5°, 7:1; at 22°, 9; at 53°, 17; at 85°, 35; and at 102°, 48.5 atmospheres. The critical temperature of propane is 102° and the corresponding critical pressure 48.5 atmospheres. Hence, propane may be sealed safely in glass tubes when surrounded with solid carbon dioxide, and thus preserved. It is colorless and much more viscous than liquid carbon dioxide. Its density at 0° is 0.536, at 6.2°, 0.524, at 11.5°, 0:520, and at 15:9°, 0.515. The examination of liquid ethane was more difficult owing to its lower boiling point. The gas was prepared from ethyl iodide and the zinc-copper couple of Gladstone and Tribe. Although a mixture of solid carbon dioxide and ether was found insufficient to liquefy ethane, liquid ethylene afforded the necessary low temperature and the ethane readily condensed to a liquid in the boiling point apparatus, where its temperature was determined by means of a thermo element. When in regular ebullition, its boiling point was found to be - 89:;° at 735mm pressure. The determination of the pressure at different temperatures was effected in a modified Cailletet apparatus. The critical temperature was found to be 34.5° and the critical pres. sure 50 atmospheres. The meniscus became hazy at 32° and disappeared completely only at 40°. At 31°, the pressure is 11 atmospheres ; at —20°, 14:5; at -11°, 18:3; at 0°, 23:3; at +15°, 32:3; and at +34.5°, 50. The density of liquid ethane at 0° is 0.446, and at 10:5°, 0.396.Liebig's Annalen, cclxxxii, 229, October, 1894.

G. F. B. 5. On the Effect of Low Temperatures on Chloroform. —An interesting example of the anomalous behavior of substances at very low temperatures has been observed by Raoul Pictet in the case of chloroform. In the preparation of this substance in the pure state by crystallization at – 69° he made use of two copper refrigerators, of capacities of 2} and 32 liters respectively. In the first series of experiments, the former only was used. About 2 kilograms of commercial chloroform in a glass cylinder was placed in the refrigerator and cooled to – 120°, as indicated by an ether thermometer. The chloroform appeared turbid at

-40° or – 50°, and was filtered and again cooled. At –68.5°, the cooling ceased and very transparent crystals of chloroform appeared on the walls of the tube. Owing to the anæsthetic advantages of the pure chloroform thus obtained, attempts were

made to secure larger quantities, by operating in the larger vessel. But it was found that here the chloroform could be cooled to - 81° without a trace of crystallization. Indeed chloroform crystals produced in the smaller vessel at —68.5°, dissolved at once when placed in the larger one at -81o. Finally the whole tube with crystals on its walls and liquid surrounding them, was immersed at -- 68.5° in the liquid chloroform at -81° And although the thermometer fell from the higher to the lower temperature, the crystals actually dissolved before the observer's eyes. The author accounts for this result on certain theories of his own concerning radiation. - Nature, li, 20, November, 1894. See also C. R. cxix, 554, 1894.

G. F. B. 6. On Symmetrical Di-ethyl hydrazine. -Although the discoverer os bydrazine, Curtius, succeeded in obtaining the symmetrical di-benzyl hydrazine and Fischer the unsymmetrical di-ethyl hydrazine, yet it is only recently that the symmetrical di-ethyl derivative of hydrazine CH NI.NHC,H, or symmetrical hydrazo-ethane, has been isolated. This has been done by HARRIES in the laboratory of the University of Berlin, by a somewhat indirect though in practice quite simple series of reactions. As the first step, a remarkable hydrazine derivative was first prepared by acting on di-formyl hydrazine with sodium and then decomposing the product with lead acetate. In this derivative one hydrogen atom of each amidogen radical was replaced by the radical formyl and the other by lead; its constitution | CHO-NG,

Pb. When warmed in a sealed tube with ethyl

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iodide, together with sand and magnesia, the lead atom is replaced by two ethyl groups. The substance thus obtained, a volatile liquid, is then treated with fuming hydrogen chloride, which removes the formyl groups and produces the hydrochloride of symmetrical di-ethyl hydrazine; the free substance passing over at 85° on distillation with potassium hydrate. It is a liquid with an agreeable ethereal odor which reduces Fehling's solution with great energy and also silver nitrate even in the cold. Toward certain oxidizing agents, especially yellow mercuric oxide, it reacts violently, yielding mercury di-ethyl and azoethane C.H.N=NC,H.-Ber. Berl. Chem. Ges., xxvii, 2276, September, 1894.

G. F. B. 7. On Carbazide and Di-urea.-In conjunction with CURTIUS, HEIDENREICH bas produced two remarkable nitrogen compounds, one of which is carbazide or carbonyl nitride CON, and the other is di-urea CO(NH.NH),CO. The former is produced by the action of sodium nitrite on the hydrochloride of carbohydrazide. It is a colorless oil which explodes violently on being touched. The latter is obtained when the compound

1 ( NH:C00C,H, ..

and 7 NH•COOC H. 18 heated to 100° with hydrazine hydrate in a sealed tube.It is crystalline and very stable and acts like a strong monobasic acid. -Ber. Berl. Chem. Ges., xxvii, 2684, October, 1894. G. F. B.

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