June lo. 1897] 



NATURE 



143 



of the heat of neutralisation of an acid by a base with the aid 

 of the views developed in the preceding papers, and thus again 

 -hows that the electrolytic dissociation hypothesis is unnecessary. 

 -A comparative crystallographical study of the normal selenates 

 of potassium, rubidium and cresium, by A. E. Tutton. The 

 author is enabled, from the results of a very complete crystallo- 

 s^raphic examination of the selenates of potassium, rubidium 

 and civsium, to extend his previous conclusions deduced from a 

 study of the sulphates and double sulphates of these three alkali 

 metals ; he shows that the characters of the crystals of iso- 

 inorphous series are functions of the atomic weight of the 

 interchangeable elements, belonging to the same family group, 

 which give rise to the series. — The platinum-silver alloys ; their 

 solubility in nitric acid, by J. Spiller. The usual statement 

 that, on dissoh-ing platinum-silver alloys in nitric acid, from 

 5 to 9 per cent, of platinum dissolves with the silver, 

 seems erroneous ; the author only succeeded in causing about 

 1 per cent, of platinum to accompany the silver into solution. 

 — Dalton's law in solutions. The molecular depression of 

 mixtures of non-electrolytes, by M. Wilderman. — The action of 

 bromdiphenylmethane on ethyl sodacetoacetate, by G. G. 

 f Henderson and M. A. Parker. 



Edinburgh. 

 Royal Society, May 17,— Sir Arthur Mitchell, K.C.B., in 

 the chair. — An obituary notice of the late Dr. E. Sang was 

 read by J. Bruce Peebles, Esq., in which he emphasised the 

 desirability of the purchase by Government, or some learned 

 Society, of Dr. Sang's invaluable logarithmic tables. — Dschabir 

 Ben Hayyan, and the chemical writings ascribed to him. 

 Part ii., by Prof. John Ferguson.— A communication was read 

 by Percy H. Grimshaw, on some type specimens of Lepidoptera 

 and Coleoptera in the Edinburgh Museum of Science and Art. 

 The paper dealt with 52 species of butterflies and 19 of beetles, 

 the type specimens of which had been discovered by the author 

 in a collection purchased by Edinburgh University from M. 

 Dufresne, of Paris, in 1819, and afterwards transferred to the 

 museum. The most important results embodied in the paper 

 are as follows. One of the beetles has been found to be the 

 type of a new genus, the specimen in question being probably 

 unique ; it has been found necessary to re-name one species of 

 butterfly and one beetle ; errors have been corrected in 

 synonymy, &c., in the case of 19 species ; and 8 species 

 hitherto wrongly placed have been referred to their proper 

 genera. The type specimens, together with coloured drawings, 

 by Mr. Grimshaw, of the more important, were exhibited at the 

 meeting. The same author read a short account of a melanic 

 specimen of Hestina nama, Doubleday, which had been found 

 in a small collection of butterflies purchased by the museum in 

 1890. The specimen described is very close, indeed to the 

 aberration named by Oberthiir inelanina ("Etudes d'Ento- 

 mologie," xx. 1896, p. 30, tab. 10, No. 177), but differs in 

 several particulars, being generally of a darker tint, the inner 

 series of white markings on the fore wing, and the ferruginous 

 border of the hind wing being absent. The specimen and a 

 coloured drawing of the same were exhibited. 



Paris. 

 Academy of Sciences, May 31. — M. A. Chatin in the 

 chair. — New studies concerning the history of the lunar surface, 

 by MM. LcEwyand Puiseux. — On the disaggregation of comets. 

 Effect of Jupiter upon short-period comets, by M. O. Callandreau. 

 Regarding a comet as consisting of a swarm of particles of 

 spherical form, the density either being constant or varying only 

 with the distance from the centre of the swarm, an expression 

 is theoretically deduced giving the relations which should 

 exist between the distance from the sun, the velocity, the ratio 

 of the product of the masses of the sun and comet to the 

 attraction constant, and the limiting radius of the orbit of 

 an external particle. Under certain conditions the com- 

 bined effect upon the disaggregation of the comet of the sun 

 and Jupiter, near aphelion, may exceed that of the sun 

 near perihelion.— Gradual flow of liquids in channels of large 

 section. Fundamental equations, by M. J. Boussinesq. — 

 On the liquefaction of fluorine, by MM. II. Moissan and 

 J. Dewar (see p. 126). — On the function of humic materials 

 in the fertility of soils, by M. Armand Gautier. — Physiological 

 researches on the sphincter ani muscle, peculiarity shown by its 

 reflex innervation and contraction, by MM. S. Arloing and 

 Edouard Chantre. — M. Bouquet de la Grye announced to the 



NO. 1441, VOL. 56] 



Academy the loss it had sustained by the death of M. Leopold 

 Manen, Correspondant for the Section of Cieography and 

 Navigation. — Report on the precautions necessary in the 

 installation of electric conductors in the neighbourhood of 

 powder magazines. The Committee report that no distinction 

 can be drawn between telephone or telegraph wires and electric 

 light mains. A distance of 10 metres would appear to be 

 sufficient to avoid all risk with underground wires. The same 

 distance is necessary in the case of water and gas pipes, as under 

 certain conditions of leakage from neighbouring conductors they 

 niay become dangerous. For overhead lines a much greater 

 distance is advisable, at least 20 metres. — Action of zinc and 

 other metals upon the photographic plate, by M. R. Colson. — 

 On partial differential equations of the second order the two 

 systems of characteristics of which are confused, by M. E. von 

 Weber. — On systems of complex numbers, by M. E. Cartan. — 

 On the convergence of uniform substitutions, by M. E. M. 

 Lemeray. — On the small periodic movements of systems, by M. 

 P. Painleve. — On the efficiency of gears, by M. L. Lecornu. — 

 On a means of recognising a good cryoscopic method, by M. 

 Ponsot. — On the purification of cerium, by MM. Wyrouboff and 

 A. Verneuil. The oxides arising from the ignition of the 

 oxalates are dissolved in nitric acid, and ammonium nitrate 

 added in certain proportions to the warm solution. The whole 

 of the cerium existing as CegO^ is precipitated as a basic nitrate 

 which contains neither didymium, lanthanum, nor yttrium 

 earths. — Remarks by M. Moissan on the preceding paper. By 

 fractionally dissolving impure cerium carbide in dilute acids, the 

 solution obtained furnished on simple calcination a perfectly 

 white oxide of cerium. — On the alloys of the silver- 

 copper group, by M. F. Osmond. — The phosphorescence 

 of strontium sulphide, by M. Jose Rodriguez Mourels. — 

 Contribution to the study of the preparation of ordinary ether, 

 by M. L. Prunier. The presence of sulphur dioxide among the 

 usual products of the crude ether distillate, is accounted for by 

 the formation of ethyl isethionate, CHg.OH.CHa.SOj.OCjHs, 

 which splits up at 140° into SOg and alcohol.— On some com- 

 binations of phenylhydrazine with metallic chlorides, by MM. J. 

 Ville and J. Moitessier. — Apparatus for the commercial analysis 

 of gases, by M. Leo Vignon. The apparatus is of the Orsatt 

 type ; but calculations are given, taking into account the effects 

 of the dead space, so considerable in this class of instrument. — On 

 the products of decomposition of calcium carbide, and on its 

 employment as a phylloxericide, by M. E. Chuard. After the 

 acetylene has been produced by the action of water, ammonia 

 continues to be slowly given off. By preparing a carbide rich 

 in phosphide, a phosphocarbide is produced possessing excep- 

 tionally powerful insecticidal properties. — New order of Insecti- 

 vora of the middle Miocene at Grive-Saint-Alban (Isere), by 

 M. Claude Gaillard. — A self-recording balance, by M. G. 

 Weiss. Designed more especially for physiological purposes. 

 — Remarks on the preceding paper, by M. Bouchard. — On the 

 umbilical vesicule of the Cheiroptera, by M. Mathias Duval. — 

 Medical statistics of the army of occupation at Cochin China, 

 by M. Bonnafy. — On cases of radiographic erythema of the 

 hands, by MM. Paul Richer and Albert Londe. — On the 

 application of photography to the registration of effluvia given 

 off by living beings in both normal and pathological states, by 

 MM. Luys and David. — On aurora borealis, by M. E. M. 

 Pozzi. — On a general equation of fluids, by M. G. Perry. 



New South Wales. 

 Linnean Society, March 31.— The President, Mr. Henry 

 Deane, in the chair. — The President delivered the annual address. 

 The special subject of the address was an expansion of matters 

 treated of in that of the previous year, namely, a consideration of 

 the relations of the fauna and flora of Australia to those of other 

 parts of the Southern Hemisphere. The affinities of the floras 

 of the Cape of Good Hope and of West Australia ; of South- 

 eastern Australia and New Zealand, and of South America ; and 

 the discovery of fossil marsupials of an Australoid type in La 

 Plata and Patagonia were passed in review ; and the important 

 bearing of evidence of this kind on the question of former possible 

 land-connections between these countries where now deep seas 

 are believed to exist, was discussed. Other cognate subjects 

 touched upon were the moot subject of the permanence of ocean 

 basins and continental areas ; the present state of knowledge of 

 the rigidity of the earth ; and the causes of extreme changes of 

 climate in past geological ages. The address concluded with 

 some references to the earliest known dicotyledonous plants in 



