June 2, 1904J 



NA TURE 



119 



the best screen for work of this kind is made from a satu- 

 rated solution of acetate of copper many times filtered, lo 

 which a very small quantity of methylene blue should be 

 added. Sunlight with a heliostat was used, and the light 

 made oblique in one azimuth. The theoretical resolving 

 limit for oblique light may be roughly taken at 100,000 

 times the N..A. of the objective. Dr. Hebb said he saw 

 this plate exhibited at the Royal Society's conversazione, 

 and though it was certainly resolved, he remarked that 

 some of the lines appeared weaker than others. Mr. E. E. 

 Hill said this was due to the fact that the objective used 

 had an aperture of only 11 N..\. 



DUIJLIS. 



Royal Dublin Society, April 19. — Prof. E. J. McWeeney 

 in the chair. — Mr. G. II. Carpenter read a paper on 

 injurious insects, &c. , observed in Ireland during the year 

 1903. The prevalence of the black-currant mite (Eriophyes 

 ribis) in certain districts was mentioned, and attention was 

 directed to the economic importance of some species of 

 springtails {^-g- Achonttcs ar}tiatiis and Lipura anibitlans) 

 on account of their habit of attacking healthy seeds and 

 fruits. — Prof. J. .A. McLelland read a paper on the pene- 

 trating radium radiation. .'\s the 7 rays act in some ways 

 more like charged particles than lilce Rontgen rays, the 

 author has made experiments to test directly whether or 

 not a charge is carried by the y rays. No charge was 

 detected. The sensitiveness of the apparatus is defined by 

 showing how small a fraction of the $ radiation could have 

 been detected by means of the charge on the 8 particles. 

 The second part of the paper deals with the absorption of 

 y rays by different substances, and it is shown that these 

 rays are to some extent heterogeneous, and that the absorp- 

 tion-density law is followed with remarkable closeness when 

 one deals only with the most penetrating of the y rays. — 

 Dr. W. E. Adeney made a further communication on 

 photographs of spark-spectra from the 21-5 feet Rowland 

 spectrometer in the Royal University, Dublin. In this paper 

 the author deals with the wave-lengths of the lines in the 

 ultra-violet spark-spectra of platinum and chromium. These 

 have been calculated from measurements made from photo- 

 graphs of the first order of spectra, reproductions of which 

 were published in the first part of this work {Trans. Roy. 

 Dubl. Soc, vol. vii., 1901, p. 331). Kayser's measurements 

 of well defined lines in the arc-spectrum of platinum have 

 been employed as standards. — Prof. E. J. McWaeney read 

 a paper on the cases of carbon-monoxide asphyxiation that 

 have occurred in Dublin since the addition of carburetted 

 water-gas to the ordinary coal-gas. .-Xttention was first 

 directed to the increase of carbon-monoxide in the Dublin 

 coal-gas by Prof. Emerson Reynolds, F.R.S., in a paper 

 read before the Royal Dublin Society in 1900 (Scientific 

 Proceed., vol. ix. p. 304). Analyses made for Prof. 

 McWeeney by Mr. J. Holm PoUok showed 172, i6-8 and 

 140 per cent, of CO respectively. The author proceeded to 

 recount in detail the circumstances attending seven fatal 

 cases that had come under his notice during the past three 

 years, each of which presented special features of interest. 

 In one of the cases, which had a fatal termination, the 

 haemoglobin of the blood was saturated to the extent of 

 73 per cent, with carbon monoxide ; in another the latter 

 amounted to 87-7 per cent. The victim in this case, a young 

 man, was asphyxiated in his bath by the CO-containing 

 fumes escaping from a badly constructed and unventilated 

 " geyser." The author concluded by emphasising the need 

 for increased caution imposed by the more deadly nature 

 of the gas now supplied. 



P.^RIS. 



Academy of Sciences, May 24. — M. Mascart in the chair.— 



On tile limits of sensitiveness for odours and emanations : 

 M. Berthelot. The rate of loss of. musk and iodoform 

 under certain conditions is compared with emanations from 

 a small quantity of a foreign element mixed with a large 

 quantity of an element not giving an emanation. — On 

 7-diphenylanthracene and on the hydride of symmetrical 

 y-diphenylanthracene : .\. Haller and A. Guyot. Phenyl- 

 oxanthranol reacts with phenyl-magnesium bromide, giving 

 about 50 per cent, of the expected diol. The replacement of 

 the phenylo.xanthranol by its methyl ether in this reaction 

 gives a nearlv theoretical vield. This, on reduction with 



NO. 1805, VOL. 70] 



sodium amalgam, gives the dihydride of diphenylanthracene. 

 — On some new facts observed by means of a phosphorescent 

 screen : E. Bichat. — The direct hydrogenation of the 

 homologues of aniline : Paul Sabatier and J. B. 

 Senderens. By passing a mixture of hydrogen and the 

 vapours of the alkyl-anilines over reduced nickel at 160° C. 

 to 180° C, cyclohexylethylamine, cyclohe.xyldiethylamine 

 and cyclohexyldimethylaniline have been obtained, the 

 physical properties of which are given. Cyclohexylmethvl- 

 aniline was obtained with difficulty from methylaniline by 

 this reaction. — The detonation under water of explosive sub- 

 stances : M. Jacob. The phenomena of propagation of 

 the motion are completely difi'erent in the cases where the 

 coeflScient of compressibility is supposed constant and where 

 it is taken as variable. In the first case, the speed of 

 propagation of the motion is constant, in the latter it is 

 variable, and increases with the pressure. — On the energy 

 in the so-called statical actions, its relation with the quantity 

 of motion and its differentiation from the work : Ernest 

 Solvay. — The resistance of the air. The comparison of 

 the direct resistances of different aerial vanes ; numerical 

 results : Ch. Renard. These results were obtained with 

 the dynamometric balance previously described by the 

 author, and prove the law of the square of the velocity to 

 be exact. Numerical results are given for the coefficients 

 of vanes of different shapes. — On an instrument designed 

 to facilitate calculations in screw-cutting : M. Moehlen- 

 bruck. — On the thermal ionisation of saline vapours : 

 G. Morcau. A current of air drawn through a saline 

 solution is heated in a porcelain tube to about 1000° C, and 

 the conductivity measured. It was found that the ionisation 

 of the potassium salts studied was not analogous to that 

 observed in a flame, where the influence of the acid radical 

 is very small. The mobilities of the ions also differ in the 

 two cases. — The cryoscopic study of solutions of antimony 

 sulphide ; MM. Guinchant and Chretien. The lowering 

 of the melting point of pure antimony sulphide by varying 

 quantities of lead and silver sulphides was determined by a 

 thermocouple, the temperature being maintained by an 

 electrical resistance furnace of nickel wire. The average 

 cryoscopic constant found was 790. The value for the latent 

 heat of fusion deduced by the application of van 't Hoff's 

 formula was 16-7 calories; the value determined direct was 

 found to be 17-5 calories. The experimental results obtained 

 for the lowering of the melting point of antimony sulphide 

 by metallic antimony are in accord with the view that the 

 antimony is in the atomic condition. — The estimation of 

 atmospheric formaldehyde : H. Henriet. The aldehyde is 

 estimated by drawing the air over mercuric oxide mixed 

 with glass wool at a temperature of 250° C, and estim- 

 ating the carbon dioxide formed. The accuracy of the 

 method was proved by blank experiments with known 

 amounts of formaldehyde. The conclusion is drawn from 

 these experiments that formaldehyde exists in the air in the 

 proportion of from 2 to 6 grams per 100 cubic metres of 

 air, this being very large compared with ozone, which is 

 present to the extent of 2 or 3 milligrams in the same 

 volume. The author proposes to make a study of its physio- 

 logical action. — A method for the characterisation of the 

 fatty acids : Ren^ Locquin, The sodium salt of the acid 

 is treated in ethereal solution with monochloracetone. and 

 the acetol ester thus produced transformed into its semi- 

 carbazone, the melting point of which is taken. The melt- 

 ing points of five semicarbazones derived from five fatty 

 acids are given. — The transformation of ortho-azo-alcohols 

 into indazyl derivatives : P. Freundler. — The limit of com- 

 bination of diazobenzene and phenol : Leo Vignon. — The 

 modifications of the radiations from the nervous centres 

 under the action of anaesthetics : Jean Becquerel and .Andre 

 Broca. From the variations of the ji-rays, as measured 

 by the lustre of a phosphorescent screen, the action of the 

 anesthetic can be followed, the point when danger to life 

 commences and the point of death being easily dis- 

 tinguished. — On a physical proof of the adaptation between 

 natural reagents and their perceptive organs : Augustin 

 Charpentier. — The action of the ii-rays on biological 

 phenomena : M. Lambert and Ed. Meyer. — On cases of 

 rapid expulsion of calculi by d'.Arsonvalisation : A. Moutier. 

 — On the sterilisation of cork : F. Bordas. Superheated 

 steam w'as found to give the best results. — Study of the 



