June 15, 1905J 



NA TURE 



16 



duced. The sterility is confined to the male organs, and 

 the development of the embryo-sac is normal. — Crosses 

 between fully fertile varieties of barley and varieties bear- 

 ing unisexual and sexless flowers : R. H. Biffen. — The 

 seed-bearing habit in the Lyginodendreje : E. A. N. Arber. 

 Although the seed (Lagenostonia) of Lyginodendron, one of 

 the most fern-lil<e of Upper Palaeozoic plants, is known, 

 there has, so far, been no evidence as to the manner in 

 which the seeds were borne. A new species, Lngenostoma 

 Sinclair!, has, however, been recently discovered, in which 

 the seeds are still attached to a highly branched axis, which 

 is of the nature of a compound frond with reduced lamina. 

 In this respect the Lyginodendrea; agree with the other 

 Icnown members of the class Pteridospermes. — Experiments 

 on penetrating radiation : H. L. Cooke. The experiments 

 described are in continuation of a previous research by the 

 author on penetrating radiation. By means of a small 

 portable ionisation vessel the radiation in the Cavendish 

 Laboratory is compared with that on the roof of the build- 

 ing : also when the apparatus is buried in earth, and when 

 deeply submerged in water. .A discussion of the results 

 follows. 



Dublin. 

 Royal Dublin Society, May l6.— Dr. \V. E. Wilson, F. R S., 

 in the chair. — The influence of water-vapour upon noc- 

 turnal radiation '.J. R. Sutton, The author shows a con- 

 nection between the rate of cooling of a thermometer 

 exposed between 8 and lo p.m. near the surface of the 

 ground and the relative humidity of the atmosphere, and 

 points out that his observations will not permit of any 

 such connection between the rate of cooling and the abso- 

 lute humidity. The observations were made at Kimberley, 

 South Africa. — On floating breakwaters ; Prof. J. Joly. 

 .\ description of breakwaters which will not rise and fall 

 to the motion of small waves, and will not transmit them. 

 These breakwaters are suitable for use in the shallower 

 waters of partially protected localities. — The gases liberated 

 on pulverising minerals — monazite : R. J. Moss. On 

 reducing Norwegian monazite to powder in vacuo gas was 

 obtained in the proportion of nearly 004 c.c. per gram of 

 the mineral ; 100 volumes of this gas contained ; — hydrogen, 

 45-63 volumes : helium, 763 ; nitrogen, 28.93 ; oxygen, 

 7 09 ; carbon dioxide, 10 67. The nitrogen and oxygen 

 being in atmospheric proportions were probably due to 

 leakage. In addition to those gases a small quantity of 

 water was liberated in the pulverisation of the mineral. 

 Relatively to the helium, the quantity of hydrogen is much 

 greater than was found in gas obtained by the same method 

 from pitchblende. 



Edinburgh. 

 Royal Society, May 15. — Sir John Murray in the chair.— 

 A new form of bolometer adapted for physiological investi- 

 gation : Dr. W. Colquhoun. By using thin metal 

 gratings of low resistance in a Wheatstone bridge arranged 

 as delicately as possible, the author was able to demon- 

 strate with it the heat produced by the beating of a frog's 

 heart. — The magnetic quality of a Boschovichian assem- 

 blage of molecular magnets : Dr. W. Peddie. This paper 

 gave a development of the theory of molecular magnetism 

 which applies to crystals of the cubic system. The close- 

 packed arrangement of centres was adopted, but similar 

 treatment would apply to any other arrangement. The 

 results were applied to the experimental data obtained by 

 Weiss in observations on magnetite. The conclusions 

 were : — (i) the theory is capable of giving a good account 

 of observed phenomena; (2) in Wallerant's formula, which 

 gives the correct mathematical relation between quantities, 

 the quantities which he interprets as magnetisation and 

 external force should be interpreted as internal force and 

 magnetisation respectively. Here " internal force " means 

 I he force exerted by the group of molecular magnets. The 

 internal action is completely represented by the quartic 

 surface x'^+y'^+s'' = i. — Suggestions towards a theory of 

 electricity based on the bubble atom : J. Fraser. This 

 extension of a previous communication on the constitution 

 of matter consists essentially of suggestions without rigid 

 mathematical development. The treatment of conduction 

 was of interest as suggesting a possible model of a 

 dynamical system the properties of which simulate those 



NO 1859, VOL 72] 



of an electric conductor. — The N'udibranchiata of the 

 Scottish National Antarctic Expedition ; Sir Charles Eliot. 

 The paper contained the description of two new genera 

 and two new species. 



M.ANCIIESTER. 



Literary and Philosophical Society, Apiil 4.— Prof. 

 W. Boyd Dawkins, F.R.S., president, in the chair. — 

 Portion of a stem of Sigillaria vascularis giving off a 

 branch with the structure of Lepidodcndron selaginoides, 

 thus confirming Dr. Williamson's conviction of the identity 

 of these two Coal-measure plants : Prof. F. E. Weiss and 

 J. Lomax. — Notes on the Wilkinsons, ironmasters : F. 

 Nicholson. 



April 18. — Prof. W. Boyd Dawkins, F.R.S., president, 

 in the chair. — A new method of producing coloured 

 diffusion bands : H. Stansfield. One surface of a piece 

 of plate glass, rendered diffusive by spoiling the polish or 

 coating it with a diffusing film of resin or butter, was 

 fixed so as to be nearly in contact with the reflecting 

 surface of a polished silver mirror, the surfaces being 

 separated at the corners by a single thickness of stamp- 

 edging. Greater dispersion of the colours is obtained in 

 thts way than by breathing on the glass surface of a 

 silvered mirror, as the air film can be made much thinner 

 than the mirror glass. — Notes on chlorine : C. H. Burgess 

 and D. L. Chapman. 



May 2. — On some constituents of Manchester soot : 

 Prof. E. Knecht. The author pointed out at the outset 

 that smoke and soot did not consist of carbon alone, as 

 was popularly supposed, and went on to show that the 

 soot obtained from the " fat " coal which is used in the 

 Manchester district contains at least 50 per cent, of sub- 

 stances other than carbon. A variety of interesting pro- 

 ducts were shown which had been isolated from an average 

 sample of household soot collected in Manchester. These 

 included snow-white samples of ammonium chloride, 

 ammonium sulphate, calcium sulphate, and a beautifully 

 crystallised paraffin hydrocarbon which was similar in 

 properties and composition to one which was known to exist 

 in bees' wax. The amount of heavy hydrocarbon oils con- 

 tained in our household soot was found to be no less than 

 13 per cent. From the brown coloured acid constituents 

 the author had prepared a dye-stuff which was capable 

 of producing absolutely fast shades of brown on cotton, 

 dyed samples of which were shown. Comparative analyses 

 of samples of soot collected in London and in Prague 

 showed that these (especially that from Bohemian lignite) 

 were much cleaner than the Manchester soot. After com- 

 menting on the drawbacks attendant on the presence of 

 soot in our atmosphere, chiefly due to household fires, the 

 lecturer expressed the opinion that no amelioration could 

 be hoped for unless the use of more efficient fire-grates 

 could be made compulsory. 



P.^RIS. . 

 Academy of Sciences, June 3. — M. Troost in the chair. — 

 Observations on the methods employed in calorimetry, with 

 especial reference to the determination of the heat of com- 

 bustion of organic compounds : M. Berthelot. A 

 polemical paper in reply to Julius Thomsen. The author 

 strongly supports the accuracy of the results obtained by 

 the calorimetric bomb as against the combustion under 

 atmospheric pressure. — On the dynamics of the electron : 

 H. Poincare. A discussion of a recent paper by Lorentz 

 on electromagnetic phenomena in a .system moving with 

 any velocity smaller than that of light. — Photographs in 

 colour of the spectrum, negative by transmission : G. 

 Lippmann. In the case of photographs on bichromatised 

 gelatin films it has been hitherto necessary to moisten 

 the film each time it is desired to observe the colours. 

 By alternate treatment with solutions of potassium iodide 

 and silver nitrate the colours become permanent and 

 visible after drying. — The preparation and properties of 

 the chloride and bromide of thorium : H. Moissan and 

 M. Martinsen. The chloride of thorium was prepared 

 by the action of well dried chlorine on metallic thorium 

 prepared in the electric furnace. Owing to the extremely 

 hygroscopic properties of the thorium chloride it wa-i 

 impossible to transfer it mechanically to a vessel for 

 analysis, and it was therefore volatilised directly into a 



