July 12, 1877] 



NA TURE 



219 



Quincke. — On the excitation of electricity through gliding 

 friction, by M. Riess. — On unipolar induction of a solenoid, by 

 M. Zbllner. — Remarks on Prof. Neumann's paper on the number 

 of electric materials, by M. Ediund. 



No. 5. — On the reflection of heat rays from metals, by M. 

 Knoblauch. — On the treatment of ponderomotive and electro- 

 motive forces occurfiiig between linear currents and conductors, 

 according to the fundamental laws of electrodynamics, by M. 

 Clausius. — On the tensions of vapour in dissociation of salts 

 containing water of crystallisation, by M. Pareau. — On the co- 

 efficients of temperature of heat conduction of air and hydrogen, 

 by M. Winkelmann. — On the phenomena of motion of electrified 

 mercury in glass vessels, by M. Herwig. — On divergences from 

 Ohm's law in metallically conducting bodies, by M. Braun. — On 

 the theory of unipolar induction and Pliicker's experiment.', by 

 M. Riecke. — On heat conduction in sulphate of copper, by M. 

 Pape. — Remarks on the polarisation of the rainbow, by M. 

 Lommel. — On the history of the invention of the areometer, by 

 M. Gerland. — On the significance of the rhombohedric and pris- 

 matic surfaces in quartz, by M. Baumhauer. 



SOCIETIES AND ACADEMIES 

 London 

 Zoological Society, June 19. — E. W. H. Holdsworth, 

 F.Z.S., vice-president, in the chair. — The secretary read a letter 

 addressed to him by Mr. J. M. Cornely, announcing that his 

 female Hyiiropelesinirinis had just produced three young ones. — 

 Mr. J. E. Harting, F.Z.S., exhibited and made remarks on a 

 variety of the common Snipe, intermediate between the usual 

 form of that species and the so-called Sabine's Snipe. — Mr. B. 

 Tegetmeier, F.Z. S., exhibited a specimen of a curiously mal- 

 formed sternum of the Tawny Owl. — Mr. John Murray, Natu- 

 ralist to the CluilUrigcr Expedition, exhibited and made remarks 

 on a series of sharks' teeth, whales' ear-bones, and other speci- 

 mens dredged up at great depths during the ChalLnger Expedi- 

 tion. — Mr. P. L. Sclater, F.R.S., read the first of a series of 

 reports on the collection of birds made during the voyage of 

 H.M.S. ChalU>ii;er, containing general remarks on the collection, 

 which was stated to consist of about 679 skins of terrestrial and 

 19S of oceanic birds, besides a considerable series of specimens 

 in salt and in spirit, and a collection of eggs, principally of the 

 oceanic species. — A communication was read from the Marquis 

 of Tweeddale, F.R.S., containing a report on the collection of 

 birds made during the voyage of PI. M.S. Challenger in the 

 Philippine Islands. Amongst them were examples of seven 

 species new to science. — Mr. P. L. Sclater read a paper giving 

 a description of the birds collected at the Admiralty Islands 

 during the visit of the Challcngir expedition to that place. 

 Amongst these were examples of six species hitherto unknown 

 to naturalists. — A communication was read from the Rev. 

 O. P. Cambridge, C.M.Z.S., on some new species of Araneidea, 

 with characters of two new genera and some remarks on the 

 families PodoptlialmiiUs and Ditwpides. — A note was read by Mr. 

 J. H. Gurney on the breeding of the Polish swan in captivity, 

 and on the stages of plumage of the young birds. — A communi- 

 cation was read from Mr. F. Moore, in which he gave a com- 

 plete description of the Lepidopterous fauna of the Andaman and 

 Nicobar Islands, so far as is yet known. — A communication was 

 read from Mr. Herbert Druce, F. Z. S., containing a revision of 

 tha i..epidopterous genus PapJiia, with descriptions of twenty-one 

 new species. — A communication was read from Mr. K. J. Miers, 

 F. ZS., containing the description of a collection of Crustacea 

 (Decafoda and Isopoda), chiefly from South America, with de- 

 scriptions of new genera and species. — Mr. A. H. Garrod read a 

 description of the brain of the Sumatran Rhinoceros (Ccrator- 

 liinus iiimalrcmis). — A paper by Mr. A. D. Bartlett, contained 

 the description of a new Guinea Fowl, from Mombassa, in 

 Eastern Africa, based on a specimen brought home by Mr. 

 (lerald Waller, for which the name Numida eltioti was pro- 

 posed. 



Entomological Society, July 4.— Prof. Westwood, president, 

 in the chair. — Mr. J. \V. Douglas exhibited a living specimen of 

 Ceramliyx Ih-ros and a young larva of the same insect, bred from 

 a log of wood imported from Bosnia. — The president exhibited 

 some cases composed of small semi-transparent quartz-like 

 particles and constructed by the larva of a Trichopterous insect 

 inhabiting Southern Europe. They had been described by 

 Swainson in iS4oasashell belonging to the genus Thdidomtis. — 

 The' president also exhibited a plant- bug (Capsidu) found on the 



leaf of an orchis which had become covered with blisters from 

 the attack of the insect.— Mr. Jenner Weir exhibited a fema'e 

 specimen of a Cicada taken in his presence in the New Fojest 

 by Mr. Auld, who stated that he had heard it stridulaiing. Mr. 

 Douglas, however, suggested that the sound had been produced 

 by a male concealed near. — Mr. S. Stevens exhibited two living 

 specimens of Tillus uinfa'iiatiis taken on a fence near Norwood. 

 —Mr. J. P. Mansell Weale, who had just returned from Sou'h 

 Africa, exhibited a fine collection of insects from that country 

 and read a paper containing the results of his observations and 

 (xperimenis upon the breeding of Papilio tiurope and other 

 insects. — Tfie secretary read a letter from Dum'^ries stating that 

 Colias (■(/;«« had made its appearance in that di-trict in themonlh 

 of June.^The president brought before the Society the recent 

 accounts of the appearance of the Colorado beetle in Canada and 

 in Europe. 



Physical Society, June 23. — Prof. G. C. Foster, president, 

 in the chair. — Prof. \V. Grylls Adams exhibited a very complete 

 form of optical bench, which, in addition to being provided with 

 all the improvements introduced by Prof. Cliitun, carries an 

 arm which can be set at any angle to it and is provided with 

 appliances for studying a beam of light or radiant heat when it 

 deviates from the main axis of the instrument. At the base of a 

 pillar firmly clamped in any position in the manner adopted by 

 Prof. Clifton, is fixed a horizontal graduated circle, and a vernier, 

 attached to a counterpoised arm, which rotates round the axis of 

 this pillar, renders it possible to determine the angle made by 

 the arm with the bench to one minute. At the upper extremity 

 of the pillar is a steel pivot to which various appendages may be 

 clamped, and immediately below this is a second ;.'raduated circle 

 by which to determine the angular position of whatever is sup- 

 ported by the pillar. Mirrors, metallic surfaces, prisms, &c., 

 may be placed on this pillar for the reflection, refraction, diffu- 

 sion, or polarisation of heat and light. For radiant heat the 

 rotating arm carries a line thermo-electric pile and a table on 

 which absorbing media may be placed. Prof. Adams illustrated 

 the use of the instrument by projecting on to a screen the inter- 

 ference bands obtained when a beam of light, after reflection 

 I'lOm the two surfaces of a thick plate of glass, is sgain reflected 

 trom the tv.'o surfaces cf a similar plate placed very nearly 

 parallel to the first. A compensator consisting cf two plates of 

 glass of equal thickness is also added between the two thick 

 plaies, and an ingenious arrangement renders it possible to 

 incline the glasses at any angle to one another, and to move 

 them either independently or together. Me also shcv/ed the 

 efl'ect produced in the positions of the bands when the rays from 

 the two surfaces of the first plate traverse fair of different densi- 

 ties before falling on the second. The adjustment of this latter 

 was facilitated by fine screws supplemented by springs which 

 rendered it possible to give a slight movement to the plate in 

 any direction, by combining a motion of tianslation of the plate 

 parallel to its reflecting faces with a mction of rotation about a 

 vertical or horizontal axis. —Mr. F. D. Brown exhibited an ap- 

 jiaratushe has arranged, in which to compare thermometers. 

 From a brass hemispherical boiler rises a tube of the same metal 

 two inches in diameter and about two feet long ; the steam, after 

 ascending through ir, descends a metallic jacket surrounding it, 

 whence it passes into a U-shaped condenser, and from this it is 

 returned to the boiler. Tr.e upper end of the condenser is in 

 connection with a large air-tight vessel forming the base of the 

 apparatus, and in which any required degree of exhaustion can 

 be maintained by the use of Lothar Meyer's form of pump. The 

 thermometers a. e placed in tubes, which pass within the wide brass 

 tube at its upper end, and by varying the nature of the liquid in 

 the boiler, and the pressure to which it is subjected, the boiling 

 point can be retained constant at any requ'reil temperature. — 

 Dr. Guthrie and Mr. Akroyd communicated a paper on electrical 

 selection. When a metal or other body is nibbed against some 

 non-conducting substance like caoutchouc, electricity is deve- 

 loped, and the track of the metal may be readily made evident 

 by sprinkling on the caoutchouc a mixture of red lead and 

 sulphur. Ttiis sieving imparts nigative electricity to the sulphur 

 and positive to the red lead, hence that particular ingreoient of 

 the mixture is drawn to the metal track which possesses the 

 opposite kind of electricity. Iron, for example, when rubbed 

 against caoutchouc generates negative electricity, and, after 

 sprinkling the powder, the iron track is revealed by the marked 

 collection thereon of red-lead. A list of mixtures was given 

 which may be used instead cf the above, and it was shown that 

 electrical selection may prove of use (i) in making an electrical 



