FEliRQARY 2 2, 1 900] 



NA TURE 



405 



the oldest living pupil of Cauchy. It sums up the work done 

 by the Professor during the last twenty years. Several short 

 notices, notes and new publications complete the number. 



(2) The number opens with the President's (Prof. R. S. Wood- 

 ward) address, delivered before the Society at its sixth annual 

 meeting, December 28, 1899. It is entitled " The Century's 

 Progress in Applied Mathematics. " We learn from tlie ' ' Notes " 

 that the address has been printed in a separate pamphlet (25 

 cents each). — The status of imaginaries in pure geometry, by 

 Prof. Charlotte Scott, is a paper which was communicated at 

 the October meeting. Her text is the works of Von Staudt and 

 Reye. She remarks that "it is one of the axioms of modern 

 mathematics that Von Staudt placed the doctrine of imaginaries 

 on a firm geometrical basis ; but logical and convincing as his 

 treatment is, when patiently studied in all its detail, it yet seems 

 to me hardly practicable as a class- room method " ; and then 

 she proceeds concisely to examine the writings of the two above- 

 named mathematicians, so far as they treat of imaginaries in pure 

 geometry. The usual matter follows. 



BolUltino dcUa Sociedl Sismologica Italiana, vol. v. 1899- 

 1900, Nos. 4, 5. — On the present state of Vesuvius (July 3, 1899) 

 and on the endogenous rising of the new lavic cupola during the 

 months of February and March, 1898, by R. V. Matteucci. 

 — The central explosion of Etna on July 19, 1899, by S. 

 Arcidiacono.— On the activity of the volcanoes Vesuvius, 

 Etna, Vulcano, Stromboli and Santorin in the autumn of 1898, 

 by R. V. Matteucci. — The crater of Etna after the explosions 

 of July 19 and 25, 1899, by A. Mascari. Theeflfects of the ex- 

 plosions on the terminal cone and the internal condition of the 

 crater are desc»ibed. — New type of seismoscopic clock, by G. 

 Agamennone. — Summary of the seismography of the earthquake 

 of November 16, 1894, in Calabria and Sicily, by A. Ricco. A 

 reprint of a memoir already noticed in Nature. — Notices of 

 earthquakes recorded in Italy (April 23-July 21, 1898), by 

 G. Agamennone and A. Cancani, the most important being the 

 earthquakes of Tripolitza (Greece) on June 2-3, Rieli on June 28, 

 and Dalmatia on July 2, and earthquakes of distant origin on 

 April 29, May 8 and [une 22 and 29. 



SOCIETIES AND ACADEMIES. 



London. 



Royal Society, January 18.— " Further Observations on 

 ' Nitragin ' and on the Nature and Functions of the Nodules of 

 Leguminous Plants." By Maria Dawson, B.Sc. (Lond. and 

 Wales), 1 85 1 Exhibition Science Research Scholar. Com- 

 municated by Prof. H. Marshall Ward, F.R.S. 



In the continuation of the author's work (see Phil. Trans. 

 vol. 192, p. I, 1899) in the Cambridge Botanical Laboratory, 

 cases have been observed — e.g. Phaseoliis, Destnodium, Acacia 

 — in which the filaments containing the organism disappear 

 from the nodules at a very early age : no sharp distinction can 

 be drawn between these and the nodules of Pisum, Lupinus, 

 &c., where the filaments abound in much older nodules, but the 

 suggestion arises that the mode of growth depends on special 

 adaptations of the organism to the conditions in the cells of 

 the nodules in each host. A marked crystal-layer occurs in 

 the nodules of some genera ; in others — e.g. Desmodium, 

 Robinia — peculiar apple-green, nucleus- like cell contents are 

 found. The organisms are unusually large in Desmodtum, 

 Coronilla, Psoralea, and some others ; and single rods, isolated 

 from pure cultures, of those from Desmodium were observed 

 continuously under high powers in hanging drops, and their 

 growth traced. The X and Y-shaped bacteroids arise by dis- 

 tinctly lateral branching of the straight rods. After twelve to 

 fourteen days these break up into shorter rodlets. Pure cultures 

 were made on various media, and the organism was successfully 

 grown on silica jelly with nutrient salts. In seven days, at 

 17° C, colonies of the Desmodium organism were as much as 

 30 it in diameter. The author is employing this method for 

 testing the power of the organism to fix nitrogen. 



Comparisons of "nitragin" with pure cultures from /*««/« 

 and Desmodium show that all grow readily on gelatine or agar 

 with additions of extract of pea-stems, asparagin and sugar ; 

 less readily on potato. Milk is not peptonised. A thick zoo- 

 gloea forms on a decoction of peas. The organism is aerobic, 

 does not ferment sugars, and may pass through a short motile 

 stage. Other bacteriological characters are also examined, in- 

 cluding the influence of temperature on infection of the root- 

 hairs of the pea. 



NO. 1582, VOL. 6 1 



The author's experiments with \reciprocal infections of 

 organisms from one genus of Leguminosre to another, point to 

 there being but one species concerned, hut this is probably split 

 up into several culture-races, specialised to the various agricul- 

 tural and other plants concerned, as in the case of the rust- 

 fungi, yeasts, &c. 



Crop-cultures of peas infected with the organism, in sterilised 

 soil, ordinary soil, sand, sub-soils, &c., gave contradictory re- 

 sults. In a few cases a small increase was got by the use of 

 the organism alone ; but in other cases where nitrates were 

 used instead the crop was larger. When nitrates as well as 

 "nitragin" are added the crop may be even reduced. 



The conclusion derived from the various experiments, how- 

 ever, is that the presence or absence of " nitragin " is but one 

 factor in a complex problem, and that at the same time must 

 be taken into account the complicated physical and biological 

 conditions of the soil and atmospheric environments, as well as 

 the symbiotic action of the host plants, in the removal of the 

 products of metabolism from the field of action of the nodule 

 organisms. 



Chemical Society, February i. — Prof. Thorpe, President, 



in the chair. — The following papers were read. — The chlorine 



derivatives of pyridine. Part v. Constitution of citrazinic acid. 



Formation of aa'-dichloropyridine and of aa'-diiodoisonicotinic 



acid, by W. J. Sell and F. W. Dootson. — The formation of 



heterocyclic compounds, by S. Ruhemann and H. E. Stapleton. 



Benzamidine and ethyl phenyl propiolate react with formation of 



J- . A . tvtlt/CO.C: CPh 



an mtermediate product, NH-f ^p, . Vttt , 



denses, yielding 



CHPh 

 benzalphenylglyoxalidone. 



which then con- 



-N. 



?CPh 



and diphenylpyrimidone. 



C- 

 I 

 CO.NH/ 



CPh : CH . CO 



I I 



N:CPh NH. 



Urea, thiourea and guanidine condense with ethyl phenylpro- 

 piolate yielding substituted hydantoins. — The space configura- 

 tion of quadrivalent sulphur derivatives. Methylethylthetine 

 dextrocamphorsulphonate and dextro-a-bromocamphorsulphon- 

 ate, by W. J. Pope and S. J. Peachey. The authors have 

 prepared thetine salts of the constitutions 



CaHsXcj/CIL-COOH 

 CioH,50S03/^\CH; \ 



C2H5\g/CH,.COOH 

 ^"^ Q„H,4BrOS03/^\CH3 



containing optically active acid radicles, and show that the basic 

 thetine radicle is not optically active. They conclude that in a 

 thetine the sulphur atom and the four atoms directly attached to 

 it lie in one plane. — Nitrocamphane, by M. O. Forster. The 

 author has prepared nitrocamphane and pseudonitrocamphane, 

 to which he assigns the constitutions 



/CHo /CH.^ 



CgHi/ i " and CgHi^/ | 



\CH.NO2 \C:N(OH):0. 



Nitrocamphane is prepared by reducing bromonitrocamphane, 

 and yields pseudonitrocamphane when its potash solution is 

 acidified.— The absorption spectra of ammonia, &c., by W. N. 

 Hartley and J. J. Dobbie.— Isoamarine, by F. R. Japp and 

 J. Moir. The isoamarine of Feist and Arnstein obtained by 

 heating j-dibenzoyl-r-diphenylethylenediamine in hydrogen 

 chloride gas is identical with Snape and Brooke's isoamarine. — 

 On the condensation of formaldehyde with ethyl malonate and 

 on the synthesis of pentamethylenetricarboxylic acid, by J. F. 

 Bottomley and W. H. Perkin, junr. In addition to the sub- 

 stances previously described as resulting from the condensation 

 of formaldehyde with ethyl malonate, it is shown that ethyl 

 pentanehexacarboxylate, 



(CO.,Et).,CH.CH2.C(C02Et)j.CH.,.CH(C03Et).,, 

 may also be formed. It is hydrolysed by baryta, yielding pro- 

 panetetracarboxylic acid, (C02lI).,CH.CHj.CH(CO,,H)2, and 

 by hydrochloric acid with formation of the corresponding acid, 

 which on heating to 200° gives pentanetricarboxylic acid, 

 C02H.CH„.CH.,.CH(C0ijH).CH.i.CH.,.C0,H. — The volu- 

 metric estimation of potassium, by R. H. Adie and T. B. Wood. 

 The authors precipitate potassium as its cobaltinitrite, 

 KeCo.,(N02^s,3H20, 



