\April II, 1872] 



NATURE 



473 



polarised ray. A series of experiments was made on tlie valeric 

 fcids obtained from active and inactive amylic alcohols, and also 

 cii the acid obtained from leucin ; tliis latter is found to rotate 

 a ray of polarise 1 light to the right, bat not to so great an ex- 

 tent as the acid which is obtained from the left-handed amylic 

 alcohol. The acids from isobutyl cyan'de, from valerian root, and 

 frum inac;ive amylic alcohol, show very great similarity ; whilst the 

 acids from the active alcohol and from leucin agree in most of 

 their properties. The valeric acid made from inactive amylic 

 alcohol is almost certainly isopropacetic acid, and that from the 

 aclive alcohol is probably methethacetic acid, although the 

 authors consider that the latter acid might possibly be a molecular 

 (Ompound of two isomeric acids, such as isobutylformic and 

 methethacetic acids. Besides this communication, there are 

 several important physiologico-chemical papers, together with 

 translations of two others from foreign periodicals. 



The American Naturalist for February commences with an 

 exhaustive account of the Mountains of Colorado by Dr. J. W. 

 Foster, read before the Ch'cago Academy of Sciences. Mr. E. 

 L. Greene, in a short paper on the Irrigation and the Flora of 

 the Plains, shows how a gradual alteration is going on in the 

 character of the flora of those parts where a system of irrigation 

 has been established, Typba and other marsh and water plants 

 supplanting the original inhabitants of the drier plains. Mr. 

 John G. Henderson, on the former range of the buffalo, brings 

 forward evidence to show that the buffalo was at a not very remote 

 period extremely abundant over almost the whole of the Northern 

 United States, while he thinks that it is doomed in a short time 

 to become extinct like the great Irish elk, the mastodon, and the 

 dodo. The remainder of the number is occupied with reviews 

 and short notes. 



A CO.NSIDERABLE portion of the Canadian Naturalist, vol. vi., 

 No. 2, is occupied with a report of the Edinburgh meeting of the 

 British Association. Prof. Dawson continues his no'e on the 

 Post-pliocene Geology of Canada. Prof II. A. Nicholson (late 

 of Edinburgh) contributes an article on the " Colonies " of i\I. 

 Barrande, in which the best account we have yet seen is given of 

 the celebrated theory of the French pala-ontologist. Dr. J. W. 

 Anderson has a short article on the Whale of the St. Lawrence ; 

 Mr. S. W. Ford some no'es on the Primordial Rocks in the 

 vicinity of Troy, N.Y.; and Mr. E. S. Billings a paper on some 

 new species of Palxozoic Fossils belonging to the classes 

 Pteropoda and Brachiopoda. 



SOCIETIES AND ACADEMIES 



London 



Royal Society, March 21. — " New Researches on the Phos- 

 phoius bases," by Dr. A. W. Hofmann, F. R.S. Ten years since 

 the author presented to the Royal Society a series of papers on the 

 remarkable group of phosphorus compounds first discovered by 

 Then.i.rd in 1847. These researches were devoted to the investi- 

 gation of the tertiary and quartary derivatives of phosphoretted 

 hydrogen, exclusively accessible by the methods then known. 

 Since then numerous attempts have been made to f repare the 

 primary and secondary phosphines, but with no result until the 

 present time. The author wishing to obtain pure phosphoretted 

 hydrogen for lecture experiments, was led to prepare it by the 

 action of water or soda on the beautiful compound of phos- 

 phoretted hydrogen and hydriodic acid. The ease with which 

 this body decomposed led the author to think that it might be 

 made available for the production of the missing compounds. 

 For this purpose it was necessary to liberate phosphoretted 

 hydrogen in the presence of an alcohol iodide under pressure. 

 This could be done by heating together the phosphonium iodide 

 and alcohol iodide in presence of some substance capable of 

 slowly decomposing the former body, such as zinc oxide. This 

 process yields the alcoholic phosphines, easily giving rise to the 

 formation exclusively of primary and secondary phosphines. A 

 further simplification of the process was tried, namely, by 

 utilising the hydriodic acid from the phosphonium iodide in the 

 formation of the alcohol iodide to be acted on by phosphoretted 

 hydrogen. This was accomplished by digesting the phosphonium 

 iodide with the alcohol ; by this method it was found that only 

 the tertiary phosphines and the quartary phosphonium com- 

 pounds already known were produced, but which were more 

 easily and plentifully obtained by the new than by the old 

 method. The reactions by which the various groups of phos- 



phines are produced from phosphonium iodide aie as follows, 

 the reaction being assumed to take place in the methyl 

 series : — 



Primary Phosphines 

 2CHJ -1- 2 (H3P.HI) + Zn O = aFlCH^) H.P. Ill] + 

 Zn L, + H2O 

 Secondary Phosphines 

 2 CH3T -I- II3P. Ill + Zn O = (CH,)„ HP 4 Zn 1, + H„0 

 Tertiiry Phosphines 

 3 (CH3 . HO) + H3P . HI = (CH.,).) P . HI -H 3 ILO 

 Quartary Phosphonium compounds 

 4 (CH3. HO) -f H3 P. Ill = (CH.;)^ PI + 4 HjO 

 The primary and secondary methylic derivative; of phospho- 

 retted hydrogen are prepared by placing together in a sealed 

 tube 2 molecules of methylic iodide, 2 molecules of phospho- 

 nium iodide, and I of zinc oxide. The mixture is heated to 

 100° for six or eight hours, when the reaction is complete ; on 

 cooling the tube contains a white crystaline solid, and also a 

 considerable amount of compressed gas. The crude product of 

 the reac'ion is first treated with water, which decomposes the 

 salts of monomethylphosphine, liberating it as a gas, which is 

 collected in concentrated hydriodic acid ; and secondly with 

 potash, which decomposes the s^alts of dimethylphosphine, and 

 liberates the dimethylated phosphine as a liquid. The whole 

 process must be conducted in an atmosphere of hydrogen, as the 

 two bodies are powerfully acted on by the oxygen of the air. 



Methylphosphine CH3 H,, . P, is a colourless and transparent 

 gas of a most overwdielming odour, which, by cooling and by 

 pressure, can be condensed to a colourless liquid floating on water. 

 It boils at - 14° under a pressure of 07585 metre. At 0° it 

 began to liquefy at i \ atmospheres pressure, and at 2\ atmospheres 

 it was entirely liquefied. At 10' liquefaction commenced at 2i 

 atmospheres and was completed at 4 atmospheres pressure, and 

 at 20° under a pressure of 4 and A,\ atmospheres. The volume 

 weight of the gas was determined by decomposing a known weight ^ 

 of the iodhydrate over mercury. Experiment gave the number 

 24-35, the theoretical value being 24. Methylphosphine is nearly 

 insoluble in water free from air ; if it contain air the gas disap- 

 pears, owing to oxidation ; it is rather soluble in alcohol, more 

 especially at low temperatures; ether dissolves but little at ordinary 

 temperatures, but at 0° one volume of ether dissolves in less than 

 70 volumes of methylphosphine. When gently heated in contact 

 with air it takes fire, as it does also in pressure of chlorine or 

 bromine. By its union with acids it forms a remarkable series of 

 salts, distinguished by the remarkable property of being decom- 

 posed by water. 



The chlorhydrate is obtained by mixing methylphosphine with 

 gaseous hydrochloric acid, the gases at once condense to beautiful 

 four-sided plates; the iodhydrate CH„ PI is obtained by passing 

 the gas into a concentrated solution of hydriodic acid ; it can be 

 crystallised in plates, which may be easily sublimed. 



Dimethylphosphine (C H - ) „ H P, obtained as above, is a transpa- 

 rent colourless liquid which is lighter than water and insoluble in 

 it ; readily soluble in alcohol and ether. Its boiling point is 25°. 

 In contact with the air it instantly takes fire, and burns with a 

 powerfully luminous phosphonis flame. It unites easily with 

 acids, all its salts being exceedingly soluble. The chlorhydrate 

 furnishes with platinum perchloride a fine crystalline salt. 



Methylphosphine passed into fuming nitric acid is absorbed 

 and oxidised, with the formation of a new acid, small quantities 

 of phosphoric acid being also produced. The excess of nitric 

 acid is removed by evaporation in a water bath, and the phos- 

 phoric acid by boiling with lead oxide, which forms the lead salt 

 of a new acid A\hich is soluble in acetic acid, and lead phosphate 

 which is insoluble. The lead salt is decomposed by sulphuretted 

 hydrogen, and the acetic acid removed by evaporation, which 

 leaves the new acid as a ci-yst.i'line mass resembling spermaceti, 

 melting at 105°. Its composition is found to be CIL, H.^ PO3, 

 and may be called methylphosphinic acid. It forms two series 

 of salts, in which Hj and IL are replaced by mei.als. The 

 primary silver salt ciystallises in beautiful white needles which, 

 in contact with water, are converted into the secondary salt. The 

 lead and barium salts of this acid have also been obtained. 



Methylphosphinic acid has the same composition as methyl- 

 phosphorous acid, but they are two absolutely different bodies. 

 Methylphosphorous acid is an uncrystallisable ephemeral com- 

 pound, decomposing at a gentle heat into phosphorous acid and 

 methyl alcohol, whilst methylphosphinic acid may be distilled 

 ■without decomposition. _ 



