July 4, 1907] 



NA TURE 



237 



insect. — The significance of some secondary sexual 

 characters in butterflies : Prof. E. B. Poulton. — Report 

 of entomological observations made in South Africa during 

 the visit of the British Association in 1905 : Dr. F. A. 

 Dixey and Dr. G. B. Longstaff. 



Linnean Society, June 6. — Prof. W. A. Herdman, 

 F.R.S., president, in the chair. — Contributions to our 

 knowledge of New Zealand Holothurians ; Prof. Dendy 

 and E. Hindle. — Report on the marine fishes collected by 

 Mr. Stanley Gardiner in the Indian Ocean : C. Tate 

 Regan. The collection contained examples of nearly 200 

 species, more than fifty of which were new to science, 

 among them some remarkable new generic types. A large 

 proportion of the new species were dredged at considerable 

 depths, and the others chiefly belonged to genera the species 

 of which have been supposed to be more variable and 

 more widely distributed than proves to be the case. — The 

 Ixodids collected in the above e.xpedition : Prof. 

 Neumann. 



Physical Society, Tune 14. — Mr. H M. Elder, vice-prei-i- 

 dent, in the chair. — The electric arc : Mr. Upson, .^rcs 

 were described in which the electrodes consisted of carbon, 

 copper, iron, and aluminium in different combinations, 

 maintained in air, hydrogen, and coal-gas. With no volts 

 supply, metal arcs in hydrogen took the form of a spark 

 discharge. At that voltage the maximum length of arc 

 it was possible to obtain, with current up to 15 amperes, 

 was o"-05, except where both electrodes were of the same 

 metal. When carbon is one of the electrodes a true arc 

 is formed. If carbon is negative the maximum length of 

 arc with the above voltage is o"o7. \"oIt-ampere 

 characteristic curves were shown for arcs in air and 

 hydrogen of length o"o5. The general position of the 

 curve is determined by the material of the negative 

 electrode. With carbon negative, in hydrogen, the curves 

 for various positive electrodes very nearly coincide. With 

 carbon positive, they keep the same curvature, but vary 

 in distance apart, according to the material of the negative. 

 In general, the position of the curve is governed by the 

 negative, but its particular shape seems to come from the 

 influence of the surrounding gas.- — The Poulsen arc as a 

 means of obtaining continuous electrical oscillations : Dr. 

 J. A. Fleming, Dr. Fleming showed and described an 

 apparatus for forming an electric arc in an atmosphere 

 of coal-gas between a carbon rod kept in slow rotation 

 and a cooled copper anode, the arc being formed in a 

 magnetic field of 600 to 1000 C.G.S. units. The arc was 

 supplied with continuous current at a pressure of 400- 

 500 volts. A condenser of 0003 mfd. capacity in series 

 with an inductance of 200,000 cm. was shunted across the 

 arc, and experiments shown to prove the existence of 

 high-frequency oscillations in the condenser circuit. A 

 long resonance helix of insulated wire was then joined to 

 the condenser circuit, and when tuned to it created a 

 powerful high-frequency field round it in which vacuum 

 tubes glowed brilliantly. By vibrating or rotating a neon 

 vacuum-tube of spectrum ivpe near the helix, and showing 

 that the band or disc of light was cut up by dark spaces, 

 Dr. Fleming supported the contention that the oscillations 

 so produced are not absolutely uninterrupted, but cut up 

 into groups. — A direct-reading conductivity bridge for test- 

 ing rods of steel or other material, where there is 

 considerable range of conductivity between successive 

 specimens, and where it is necessary to eliminate the 

 resistance of end contacts : R. Appleyard. 



Chemical Society, Tune 20. — Sir William Ramsay, 

 K.C.B., F.R.S., president, in the chair. — Some properties 

 of radium emanation : A. T. Cameron and Sir W. 

 Ramsay, K.C.B. It has been discovered that the eman- 

 ation from radium undergoes a rapid change of volume 

 shortly after its change from the solid to the gaseous 

 state ; this is followed by a slow change corresponding 

 with its loss of electrical activity. It has been shown by 

 thirty sets of measurements that the emanation behaves 

 In accordance with Bovle's law, both before and after this 

 preliminary change. Measurements have been made of the 

 initial volume of the emanation obtained from a solution 

 of 87-7 milligrams of radium (metal) as bromide and 

 sulphate. From these it would appear that, instead of the 

 previously accepted value for the average life period of 



NO. 1966, VOL. 7&] 



radium, iioo years, a much shorter life must be deduced, 

 namely, 236 years. — The allinity constants of amino- 

 sulphonic acids as determined by the aid of methyl-orange : 

 V. H. Veley. The affinity constants of the aminonaphthol- 

 sulphonic acids when determined by the tintometer method 

 show, as regards the effect of the introduction of the 

 hydroxyl grouping in the naphthylaminesulphonic acids, 

 relationships similar to those observed by Ostwald bv the 

 electric conductivity method for the hydroxybenzoic acids 

 as compared with benzoic acid. One possible ;ase of 

 steric hindrance induced by the introduction of the hvdroxyl 

 grouping in the 8-positIon was noted. — Azo-derivativcs 

 of I : 3-diphenylbarbituric acid. Dynamic Isomerism among 

 the coloured hydrazones of i : 3-dIphenvlalIoxan : Miss 

 M. A. Whiteley. In order to throw some light on the 

 structure of the compounds obtained by the action of 

 aromatic diazonium chlorides on the 5-alkyl-substituted 

 derivatives of i : 3-diphenylbarbituric acid, the investi- 

 gation has been extended, and the action of the /3-substi- 

 tutrd derivatives of phenyihydrazine on 5 : 5-dibromo- 

 I : 3-diphenylbarbituric acid has been examined. The 

 results show that the yellow compounds obtained In the 

 first reaction are azo-derivatives, whilst the red ones 

 obtained In the second are hydrazones. — .\ series of 

 coloured diazo-salts derived from benzoyl-i : 4-naphthylene- 

 dlamlne : G. T. Morgan and W. O. Wootton. The 

 examination of the diazo-salts of benzoyl-p-phenylene- 

 dlamine and benzoyl-i ; 4-naphthylenedIamine has been 

 continued, and it has been found that the diazo-derivatives 

 of the latter base are extremely stable substances which 

 are invariably coloured. These coloured salts might be 

 regarded either as iyn-diazo-derivatlves or as equilibrium 

 mixtures of diazonium and syu-dlazo-derivatives, although 

 their great stability somewhat militates against the 

 assumption that they consist wholly or in part of syn- 

 diazo-compounds. — Colour and constitution of azo-com- 

 pounds, part i. : J. T. Hewitt and H. V. Mitchell. The 

 authors recently directed attention to the very marked 

 change in colour when /i-nitro-derlvatlves of arylazo-/i- 

 phenols were dissolved In alkalis. The explanation was 

 offered that, whilst benzeneazophenol forms alkaline salts 

 of corresponding constitution, the /)-nitro-derivatives 

 furnish salts with the metal attached to the nitro group, 

 and therefore diquinonoid in structure. The relationships 

 are rendered apparent by the formulas 



C^H^.N : N.C,H..OK and KO.N : C^H, : X.N : C,H, : O. 

 Comparison of the two carbo.xylic acids 



CO.,H CO.,H 



)0H and NO„;; 



"\ 



_/ 



N:N< 



\_ 



OH 



indicates that the frequency of the absorbed light is lowered 

 by increase in the length of the chain of alternate single 

 and double linkings. The introduction of substituents may 

 modify the length of the chain owing to the possibility of 

 more stable salt formation in other directions. — The 

 oxidation of hydrazines by free oxygen : F. D. Chattaway. 

 — Calmatambin : a new glucoslde : F. L. Pyman. This 

 glucoside from the bark of a West African tree, probably 

 Canthium glabrifolium, has the formula C,,H,,0,,,2H,0, 

 contains one methoxyl group, and is readily hydrolysed by 

 dilute acids and by emulsin forming calmatambetin, 

 C|3H,,0,,5H„0, together with dextrose. The former is 

 readily decomposed by the action of dilute acids, and 

 yields a small amount of a scarlet, crystalline substance, 

 C,,H,,03. — The decomposition of hyponitrous acid in 

 presence of mineral acids : P. C. Ray and A. C. 

 Ganguli. Hyponitrous acid when liberated from silver or 

 mercurous hyponitrlte by the action of dilute nitric, hydro- 

 chloric, or sulphuric acid at 25° decomposes at once 

 according to the equations (i) 2HN0 = H,0-(-N,0, 

 (2) 5HN0 = 2H,0-|-HN0,-|-4N. — The chemical composition 

 of petroleum from Borneo : H. O. Jones and H. A. 

 Wootton. The petroleum from Borneo consists of approxi- 

 mately equal quantities of homologous hydrocarbons of the 

 paraffin, cycZo-hexane, and aromatic series, and contains 

 ihe members of the naphthalene series to the extent of 

 about 6 per cent, to 7 per cent. — The synthesis of pheno- 



