March 27, 1879] 



NATURE 



499 



1. The contact difference of potentials of metals and liquid* 

 at the same temperature. 



2. The contact difference of potentials of metals and liquids 

 when one of the substances is at a different temperature from the 

 other in contact with it — for example, mercury at 20° C. in contact 

 with mercury at 40° C. 



3. The contact difference of potentials of carbon and platinum 

 w ith water, and with weak and with strong sulphuric acid. 



They mention, however, that they give only the results under 

 head No. i in the present communication, reserving those they 

 have obtained under heads Nos. 2 and 3 for a future occasion. 



Then follow arranged in the order in which they were obtained 

 from January to May, 1878, some 150 results of experiments 

 (each result given being on the average the mean of ten observa- 

 tions), representing the contact differences of potential of nine 

 solids and twenty-one liquids. The authors explain that many 

 of the results they obtained are not mentioned in the paper, 

 ha^dng been rejected on accoimt of inaccuracies arising from the 

 great delicacy of the experiments. These remarks especially 

 apply to the authors' attempts to measure the contact difference 

 of potentials between a hquid and a paste — for example, mercury 

 and mercurous >ulphate paste, great difficulty being introduced 

 by the extremely thin layer of water on the surface of the paste 

 acting inductively instead of the paste itself. They mention 

 that this difficulty is a very good example of the inaccvu-acies that 

 must have been introduced by former experimenters using a 

 moist blotting-paper surface instead of the surface of the liquid 

 itself. 



A lai^e number of discordant results were obtained in March, 

 1S78, and their explanation led to the interesting result that the 



jparent contact difference of potentials between a metal and 

 jercury, as measured inductively, varied much with small addi- 

 tions of temperature. The investigation of this apparent change 

 of contact difference of potentials with temperature led to a con- 

 -deration of the contact difference of temperature of mercury 



ith air, since, of course, in all these inductive experiments two 

 air contacts are included in the result. 



It has usually been thought that the differences of potential of 

 liquids in contact with one another were so small as to be almost 

 inappreciable in comparison with the differences of potential of 

 metals in contact ; but the authors have ascertained, among 

 other results, that strong stilphuric acid in contact with distilled 

 water, solutions of alum, copper sulphate, and zinc sulphate, has 

 a measured difference of potentials of 1*3 to \"J volts, or an 

 electromotive force more than twice as high as that of zinc and 

 copper in contact. And hence the great importance of an appa- 

 ratus that can directly measture the difference of potentials of two 

 liquids in contact. 



Zoological Society, March 18. — Prof. St. George Mivart, 

 F.R.S., vice-president, in the chair. — The Secretary called the 

 attention of the meeting to the herd of Japanese Deer {Cerxms 

 sika) in the park of Viscount Powerscourt, at Powerscourt, in 

 Ireland, now about eighty in number, and gave an account of 

 their introduction and history, from particulars supplied to him 

 by Lord Powerscourt. — A commimication was read from Dr. G. 

 Hartlaub, containing the description of a new species of Bam 

 Owl, from the island of Viti-Ievu, which he proposed .to call 

 Strix ouitaleti. — Mr. Edward R. Alston read a paper on female 

 deer \\ith antlers, showing that these weapons are not unfre- 

 quently abnormally developed in fertile females of certain species 

 of Capreolis and Cariacus, and giving reasons for believing that 

 in the ancestral forms of deer they were probably common to 

 both >exes. — Mr. Sclater made remarks on some of the rarer 

 parrot- living in the Society's Gardens. The whole series of this 

 group in the Society's collection was stated to consist of 170 

 individuals belonging to ninety -eight species. — A communication 

 was read from Prof. Garrod, F.R.S., containing notes on the 

 visceral anatomy of the Tupaia of Burmah ( Tupaia belangeri). 

 The caecum coli in this animal was stated to be small, whilst in 

 a specimen of T. tana it was ascertained to be wholly wanting. 

 — A second communication from Prof. Garrod contained notes 

 on the anatomy of Helictis subaurantiaca, in the course of which 

 he showed that the hippocampal gyrus of the brain is partly 

 superficial in this animal, which is not the ca=e in any other 

 carnivorous animal yet recorded. 



■'■ Linnean Society, March 20. — William Carruthers, F.R.S., 

 vice-president, in the chair. — The Rev. G. E. Commesford 

 Casey was elected a Fellow of the Society. — A paper by Mr. 

 Fred. Smith, on new aculeate hymenoptera from the Sandwich 

 Islands, collected by the Rev. T. Blackburn, was read. Th^ 



author states the general aspect of the series is certainly North 

 American, with mixture of a few South American forms. The ants 

 are most diverse in character, some being cosmopolitan in range. 

 The house ant of Madeira is common, and the little European 

 ant (Ponera contracia) unexpectedly turns up here. — Some ob- 

 servations on the reproduction of ferns, by Mr, T. R. Sim, were 

 also read by the Secretary in the absence of the author. Among 

 the great collection of living ferns at Kew a marked feature is 

 the large number of species that r^ularly bear adventitious buds. 

 Of a thousand species there grown barely fifty are ever found 

 without buds, and some forms produce them regularly, though 

 the normal forms do not. The above number seems very high 

 when compared with Phanerogams, where adventitious buds, 

 with some few exceptioas, may be said never to be normal. 

 Among viviparous ferns the contrary obtains, and the buds are 

 always on the same part of the plant in all the individuals of a 

 species. Polystichum angtUare, for example, bears a bud on the 

 rachis in the axil of almost every pinna on the lower part of the 

 frond, in some all up the rachis. Some Aspleniums produce 

 them on the veins of the upper surface of frond, but never 

 directly through from a sorus. Great variety in position, how- 

 ever, is manifested in different genera and species where budding 

 occurs, various examples of which the author gives. Where 

 buds become detached, considerable difference obtains as to size 

 and stage of separation, whereof many instances are pointed out 

 ind other curious instances of deviations related by the author. 

 In commenting on the subject. Sir J. D. Hooker stated his 

 belief that ferns at Kew were more bulbiferous than in their 

 natural state, possibly from more constant nutrition and warmth. 

 — The fifth contribution to the ornithology of New Guinea, 

 namely, recent collections from the neighbourhood of Port 

 Moresby, was read by the author, Mr. R. Bowdler Sharpe, The 

 interesting series dwelt on were obtained by Mr, Kendal Broad- 

 bent, and usefully compare with those got by Signor Albcrtis from 

 1 the Fly River, A parrot of the genus Aprosmictus closely 

 i resembles one from the Fly River, but nevertheless is specifically 

 ! distinct, offering thus a parallel case to the crowned pigeons, 

 ' Gonra albertisi, inhabiting Port Moresby, and G. sclaUri, the 

 ; Fly River, At present the affinities of the South- East em species 

 '; seem to be with those of Australia, a few to those of the Am 

 I Islands, — Mr, W. T, Thiselton Dyer exhibited Hdichrysum 

 \ vestitum, a perennial everlasting, from the Cape of Good Hope. 



I Anthropological Institute, March 11. — Mr, E, Burnett 

 : Tylor, D,C.L., F.R.S., president, in the chair. — The president 

 read a paper entitled " The Geographical Distribution of 

 Games," in which attention was called to the games of Polynesia 

 and America as proNing that a drift of civilisation from Asia 

 reached these regions before they were known to Eiu-opeans. 

 The draughts played in the Sandwich Islands and New Zealand 

 were not our modern game, but apparently some variety related 

 to the ancient classical game (w hich is alive in Egypt to this 

 day). It may have reached the South Sea Islands from Eastern 

 Asia, together with kite-flying, at which they were experts, and 

 which they perhaps had before the comparatively modem time 

 when it reached England. 



Royal Microscopical Society, March 12,— Dr. Beale, 

 F,R,S,, president, in the chair, — The following papers were 

 read : — Contribution to the knowledge of the British Oribatidae, 

 by A, D, Michael, F.R,M.S. — The development and retrogres- 

 sion of fat cells, by G. and F. E. Hoggan. — Microscope with 

 swinging sub-stage and improved motions, by J. Beck, F,R,M,S. 

 — The use of osmic acid in microscopical preparations, by T. J, 

 Parker, F.R.M. S.— Other papers by Prof. Keith, Mr. Tolles, and 

 Mr. Crisp were taken as read, or postponed in consequence of 

 I want of time.— The new ^^ oil immersion objective by Zeiss was 

 I exhibited, with remarks by Prof. Abbe on the Stephenson 

 I homogeneous immersion system. — A large number of objects 

 I were exhibited illustrative of the papers read and otherwise, 

 j together with microscopes and apparatus by Mr. Crisp. — Lord 

 Justice Bramwell and six other gentlemen were elected Fellows. 



Photographic Society, March 11. — James Glashier, F.R.S., 

 in the chair. — Papers were read : On coloured glass suitable for 

 the developing-room, and on the employment of quinine as a 

 substitute, by Capt. Abney, R,E., F,R,S., who, in illustration 

 of his paper, exhibited photographs of the solar spectrvmi taken 

 through various stained glasses, and stated that a combination 

 of cobalt and stained red glasses secures immunity from the 

 actinic action of light, and that collodion-films on both sides of 

 a glass, stained with either magenta, aurine, or cfarysoidine^ 



