MaV 12, 1904] 



NA TURE 



read a paper on nature's protection of insect life, illustrated 

 by colour photography, and exhibited a number of lantern 

 slides. — Mr. P. 1. Lathy communicated a paper on new 

 species of South .\mprican Erycinid^. — .Major Neville 

 Manders, R..-\.M.C., communicated some breeding e.xperi- 

 ments on Catopsilia pyraiithi, and notes on the migration 

 of butterflies in Ceylon. — .\ discussion followed on specimens 

 of the dipterous families Stratiomyida; to Crytida;', opened 

 by .Mr. G. H. Verrall, who said the object of the discussion 

 was to determine the number and distribution of the British 

 species comprised in these families. Colonel J. W. Yerbury 

 said that on behalf of Prof. Poulton he had been asked 

 to exhibit some specimens the interest of which mainly lay 

 in the specific names used, which names were useful as 

 showing the nomenclature employed by a past school of 

 dipterologists, and might give a clue to the manner in 

 which some reputed species have found their way into the 

 British list. He directed special attention to Ephippiouiyia 

 i-pliippitini, an insect reputed to have been taken at Combe 

 and Darenth Woods, but which was without doubt of 

 German origin ; Isopoi^oii hrcvirosiris, probably the identical 

 specimen referred to in Curtis's " British Entomology " as 

 having been taken on The Devil's Ditch, Newmarket; 

 and Laphria marginatu. stated to have been bred from a 

 hornet's nest. Mr. Colbran J. Wainwright, e.xhibiting two 

 specimens of Anthrax, said that hitherto Mr. \'errall had 

 believed that we had lost two certain species of Anthrax 

 in this country, .1. fciifstraliis and .4. paniscus. His two 

 specimens, though allied to .-1. patiiscus, were abundantiv 

 distinct. One had been taken by Mr. R. C. Bradley at 

 Bournemouth, the other by Mr. W. G. Blatch at Poole, but 

 at present no name could be given to the species. 



Chemical Society, April 20. — Prof. VV. A. Tilden, F.R.S., 

 president, in the chair. — The following papers were read : — 

 The vapour density of hydrazine hydrate : A. Scott. The 

 author finds that at q8°-8 the vapour density is 158 instead 

 of 25 as required by N,HjO; at 138° the dissociation into 

 NjH,-fH,0 is complete, and at higher temperatures 

 a certain amount of decomposition into nitrogen, ammonia 

 and water occurs. — The combining volumes of carbon 

 monoxide and oxygen ; A. Scott. The results of the 

 author's experiments indicate that the molecular concen- 

 tration of carbon monoxide is slightly greater than that of 

 oxygen, the combining volumes being CO : O : ; 1-9985 : i 

 with carbon monoxide from calcium oxalate, and 19994 • ' 

 with that from formic acid. — .•\ revision of the atomic 

 weight of rubidium . E. H. Archibald. The mean values 

 of the atomic weight of rubidium obtained from fourteen 

 analyses were 85-490 and 85-484 from the ratios .^gCI : RbCl 

 and .Ag : RbCI respectively. Analyses of rubidium bromide 

 led to the value 85483, obtained from either of the ratios 

 .AgBr : RbBr or .Ag : RbBr. — Experiments on the synthesis 

 of the terpenes, part i., synthesis of inactive terpineol, 

 dipentene and terpin hydrate : W. H. Perkin, jun. 

 IVntane-a7€-tricarboxylic acid, when digested with acetic 

 anhydride and subset]uently distilled, is converted into 

 5-ketohexahydrobenzoic acid. The ester of this acid reacts 

 readily with magnesium methyl iodide, yielding cis- 

 S-hydro.xyhexahydro-^-toluic acid, which with fuming 

 aqueous hydrobromic acid is converted into S-bromohexa- 

 hydro-p-toluic acid, which in turn yields A'-tetrahydro-/>- 

 toluic acid when heated with pyridine and sodium carbonate. 

 The ester of the latter with an excess of magnesium methyl 

 iodide yields terpineol. From the synthetic terpineol so 

 obtained dipentene and terpin hydrate were readily pre- 

 pared in the normal manner. — A l.x-vorotatory modification 

 of quercitol : F. B. Power and I'. Tutin. The Isevo- 

 rotatory modification described by the authors was obtained 

 from the leaves of Gymnema sylvestre, a plant belonging 

 to the family .Asclepiadacetc, and indigenous to Banda and 

 the Deccan Peninsula. — The constituents of the essential 

 oil of Californian laurel : F. B. Power and F. H. Lees. 

 The Californian laurel, Umhelliilaria californica, yields an 

 essential oil with a pale yellow colour and an odour at 

 once aromatic and irritant. It was found to contain 

 eugenol, /-pinene, cineol, safrole, eugenol methyl ether, 

 veratric acid, and a new, unsaturated, cyclic ketone, um- 

 bellulone, C,„H,,0. To the last of these the peculiar 

 pungency of the oil is due. — Some derivatives of umbellu- 

 lone : F. H. Lees. A description of derivatives of 



NO. 1802, VOL. 70] 



■jmbellulone. — .\mmoniacal double chromates and mulyb- 

 dates : S. H. C. Brig^grs. The compounds 



CuCrO,,3iNH3,lH,0 ; CuMoO,,2NH,,H,0 ; 



Cu\VO,,4NH, and ZnWO,,4NH3,3H,0 

 have been prepared and are described in the paper. — The 

 hexahydrated double chromates. .Magnesium and nickel 

 compounds : S. H. C. Brisgs. — Bornylcarbimide : M. O. 

 Forster and H. M. Attwell. .A. description of this and 

 related substances. — Reduced silicates ; C. Simmonds. 

 The substance left when lead silicates are reduced by heat- 

 ing in hydrogen is shown to be a compound which can 

 be regarded as a combination of the metal and silica, in 

 the same sense as the original silicate is a combination of 

 the metallic oxide and silica. Similar results were obtained 

 with the silicates of copper, iron, nickel and cobalt. — 

 I'icryl derivatives of urethane and thiourethane : J. C. 

 CrocKer and F. H. Lowe. The authors show that the 

 reaction between picryl chloride, thiocyanates and alcohols 

 is due to the formation of the i|/-thiourethanes of the type 

 PiN : C(SH).OX as intermediate products, which sub- 

 sequently react with picryl chloride and pass into the 

 picriminothiocarbonates PiN : C(SPi).OX. — The oxime of 

 mesoxamide and some allied compounds, part iii., tetra- 

 substituted derivatives : .M. A. Whiteley. A description of 

 a number of these compounds is given. 



Royal Microscopical Society, April 20. — Dr. Hy 

 Woodward, F.R.S., vice-president, in the chair. — A large 

 tank microscope, made by Thomas Ross, presented to the 

 society by the committee of the Quekett Microscopical 

 Club, was exhibited. It was made not later than the year 

 1870, and was designed for the purpose of examining objects 

 contained in aquaria. — The annual exhibition of pond life 

 was given this evening by fellows of the society, assisted 

 by members of the Quekett Microscopical Club. 



P.'VRIS. 



Academy of Sciences, May 2. — M. Mascart in the chair. 

 — The action of terrestrial magnetism upon a tube of nickel 

 steel (invar) intended for use as a geodesic pendulum : 

 G. Lippman, The alloy of nickel and iron known as 

 invar, which possesses a coefficient of expansion only one- 

 twentieth that of brass, has obvious advantages for pen- 

 dulum observations. This steel, however, is magnetic, and 

 it was thought possible that the disturbing influence intro- 

 duced in this way might be too large to be neglected. The 

 magnetic moment of a tube of this material was deter- 

 mined, and the possible error on a pendulum observation 

 calculated. It was found to be negligible, and hence invar 

 can be advantageously substituted for brass in the pendulu]n. 

 — The effect of small oscillations of the external action on 

 systems affected with hysteresis and viscosity : P. Duhem. 

 — Geodesic and magnetic work in the neighbourhood of 

 Tananarive : P. Colin.— Polyvalent antipoison serums. 

 The measurement of their activity : A. Calmette. The 

 antihai-molytic power is a measure of the antitoxic power 

 of a serum, and a method is described by which the former 

 can be determined in glass. — Observations of the Brooks 

 comet (1904 a) made with the bent equatorial at the Observ- 

 atory of Lyons : J. Guillaume. — On a new apparatus 

 for measuring the power of motors : Ch. Renard. 

 The axle of the motor is connected to a bar carry- 

 ing two aluminium vanes, the latter being capable 

 of adjustment as regards their distance from the 

 axis. This having been previously calibrated against 

 a dynamometer, the determination of the horse-power of a 

 motor is reduced to the determination of the angular 

 velocity. — The Adolphe bridge at Luxembourg (1899-1903) : 

 M. Sejourne. — On the comparison of spectro-photometric 

 determinations : P. Vaillant.— The sensibility of the 

 azimuth balance: V. Cremieu. .An extension of the theory 

 of the azimuth balance, a description of yvhich has been 

 given in an earlier paper. — On the role of the centrifugal 

 force component in the determination of the sense of rota- 

 tion of cyclones and yvater vortices : Bernard Brunhes 



On the electrolytic solution of platinum. .-\ new method 

 for preparing platinocyanides : Andre Brochet and Joseph 

 Petit, \^■hen platinum is used as the anode in a solution 

 of potassium cyanide, it remains unattacked. With an 

 alternating current the platinum is readily attacked, a 



