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to the very rapid action of light upon selenium. Prof. Adams 

 said that as the effects here noticed were not so rapid as in the 

 case of light they were probably due to change in temperature. 

 Prof. Bose said he had tried the effect of Hertzian radiation 

 upon thin layers of various metals and found an increase of 

 resistance in the case of selenium and a decrease in the case of 

 tellurium. The effect of radiation is confined to a few layers on 

 the surface of the conductor, but it appears that it is of the same 

 nature in continuous solids as in coherers, — .\ paper by Mr. 

 E. C. C. Baly and Dr. H. VV. Syers on the spectrum of 

 cyanogen was read by Mr. Baly. The authors have been able 

 to obtain the spectrum of cyanogen by allowing the pure gas to 

 flow through a vacuum tube and observing from the end of the 

 tube. This is necessary on account of the brown deposit of 

 paracyanogen, which renders observation in the ordinary way 

 impossible. The spectrum obtained differs from the flame spec- 

 trum, and consists of a series of equidistant flutings through the 

 whole of the red and yellow somewhat recalling those of the 

 positive band spectrum of nitrogen. The experiments prove 

 that (I ) the swan spectrum is not produced by a carbon com- 

 pound which does not contain oxygen ; (2) the swan spectrum 

 is that of an oxide of carbon, as it is only produced by carbon 

 monoxide ; and as this spectrum is changed at once into the 

 carbon oxide spectrum by admission of oxygen or by intense 

 electric discharge, and, further, as the carbon oxide spectrum is 

 invariably given by carbon dioxide, there can be no doubt that 

 (3) the swan spectrum is that of carbon monoxide and the 

 carbon oxide spectrum that of carbon dioxide. Mr. Gaster said 

 that this paper might throw light on the discussion of the arc 

 where cyanogen, carbon monoxide and carbon dioxide are 

 present. The presence of cyanogen might be able to explain 

 the hissing of the arc. — The Society then adjourned until next 

 October. 



Royal Astronomical Society, June 14. — Mr. E. B. 

 Knobel, vice-president, in the chair. — The secretary read the 

 observations of the great comet of 1901, made at the Royal 

 Observatory, Cape of Good Hope. The comet was first seen 

 on April 24 by Mr. Hills, of l^^^^enstown. Cape Colony, and 

 rapidly became a very brilliant object, with two tails, one con- 

 spicuously brighter than the other ; the fainter tail was, however, 

 considerably the longer. Photographs taken at the Cape Ob- 

 servatory with a portrait lens and with the McClean 24-inch 

 telescope were shown, and also a drawing made by Mr. Lunt, 

 of the same observatory, which showed several smaller tails 

 between the two main ones. The elements computed gave a 

 parabolic orbit. Mr. Nevill, of the Durban Observatory, who 

 was present at the meeting, said he had received a letter from 

 which it appeared that the comet was seen in Natal the day 

 before it was first detected in Cape Colony. — Prof. Turner gave 

 an account of a paper by Dr. Gill on the Oxford photographic 

 determinations of stellar parallax, and of his own reply. In the 

 discussion which ensued the Astronomer Royal and others called 

 attention to the various irregularities to which stellar photographs 

 are liable. — Lord Rosse read an account of observations of Nova 

 Persei made at the Birr Castle Observatory ; further observations 

 by Dr. Rambaut and Mr. Stanley Williams were also read. It 

 appeared that periodical fluctuations in the light of the star 

 (from about magnitude \\ to 6) still occur, though there no 

 longer seems to be any progressive decrease in its light. — Mr. 

 J. C. W. Herschel read his observations made at Cambridge of 

 the Lyrid meteors. — Mr. Horner read his spectroscopic observ- 

 ations of the sun, made in England about the time of the total 

 eclipse that was visible in Sumatra. He recorded an observation 

 of a most unusually rapid disappearance of a bright solar promi- 

 nence.— A paper from Prof. D. P. Todd was read, describing a 

 mechanical device for giving graduated exposures in photograph- 

 ing the corona. The method was a modification of that of Mr. 

 Burckhalter, obviating the necessity of using perforated plates. — 

 .\ paper, by Dr. A. W. Roberts, on the light variations of R, 

 Carina;, called attention to long and short period variations of a 

 very interesting character. 



Zoological Society, June 18.— Prof. G. B. Howes, F.R.S., 



vice-president, in the chair.— A communication was read from 

 Prof. Ray LanUester, F.R.S., on the new African mammal 

 lately discovered by Sir Harry Johnston in the forest on the 

 borders of the Congo Free State, of which two skulls and a skin 

 were e.xhibited. Prof. Lankester fully agreed with Sir Harry 

 as to this mammal belonging to a quite new and most remark- 

 able form allied to the giraffes, but having some relation to the 

 NO. 1653, VOL. 64] 



extinct Helladotherium, and proposed for it the generic name 

 Okapia, from its native name " Okapi." The scientific name of 

 this mammal would therefore be Okapia johiistoni, Mr. Sclater 

 having already given it a specific name based on the pieces of its 

 skin previously received. Sir Harry Johnston, who was him- 

 self present, gave an account of the facts connected with his 

 discovery of this animal. Sir Harry also stated that during his 

 last excursion to the north' of Mount Elgon he had found large 

 herds of a giraffe in this country which appeared to be distinct 

 from previously known forms of this mammal in having five 

 bony protuberances on the head, four placed in pairs and one 

 anterior in the middle line. Four examples of this animal were 

 now on their way home, and would soon be here to settle the 

 validity of this presumed new species. — The Hon. W. Roths- 

 child, M.P. , exhibited and made remarks upon specimens of a 

 mounted male and two unmounted males and a female of the 

 rare Abyssinian goat (Capra -ualie, Riippell), and of a mounted 

 male of the Abyssinian vio\{ (Cants siiiunsis, Riippell), which 

 had been obtained by Captain Powell-Cotton during his recent 

 visit to Abyssinia. — Mr. Oldfield Thomas exhibited a pair of 

 antlers which had been sent home by Mr. Charles Hose, who 

 had obtained them from Central Borneo. They appeared to 

 differ from the antlers of all other known deer in being highly 

 complicated and many-branched, with the upper portion curved 

 forward, and the brow-tines developed into broad horizontal 

 paddle-like structures. From this character it was proposed to 

 term the species Cerz'iis spatulalus. — Mr. R. Shelford exhibited 

 a series of lantern slides, exemplifying mimicry amongst Bornean 

 insects, especially amongst the Longicorn division of the Coleop- 

 tera. ^A communication was read from Mr. J. E. S. Moore con- 

 taining an account of his recent researches on the mollusca of 

 the great African Lakes. — .\ communication from Captain H. N. 

 Dunn contained field notes on eight species of antelopes, speci- 

 mens of which he had met with during his recent sojourn on the 

 White Nile in connection with the "Sudd" expedition. — A 

 communication was read trom Dr. R. Bowdler Sharpe on the 

 birds collected by Dr. Donaldson Smith during the early part 

 of 1889 in Northern Somaliland. Specimens of 103 species 

 were contained in the collection. — A communication from M. 

 Constantin Saturnin contained a description of a new species 

 of hedgehog from Transcaucasia, proposed to be named Erinaceiis 

 cal/ifoni. To this was added a revision of the species of the 

 genus Erinaceus of the Russian Empire. — A communication 

 was also read from Mr. J. Lewis Bonhote on the evolution of 

 pattern on birds' feathers, in which it was attempted to show 

 how all the various patterns on the feathers had been derived 

 from a common origin, and were passing or had passed through 

 a definite series of stages before reaching the shapes in which 

 they were found. — Mr. J. Cosmo Melvill read the first part of 

 a paper prepared by himself and Mr. Robert Standen, entitled 

 "The Mollusca of the Persian Gulf, the Gulf of Oman and the 

 Arabian Sea, as evidenced mainly through the collections made 

 by Mr. F. W. Townsend, of the Indo-European Telegraph 

 Service, 1S93-1900." The area embraced was determined by an 

 imaginary line (for which reasons were given) drawn obliquely 

 from Cape Ras El Had, below Maskat (lat. 22° 50' N.), and 

 Panjim, India (lat. 16°). This was the first attempt towards a 

 complete catalogue of the mollusca of this region, between 900 

 and 1000 species being named, of which more than one-third 

 were of very restricted distribution. 



Mineralogical Society, June 18. — Dr. Hugo Mliller, vice- 

 president, in the chair. — Mr. Alfred Harker gave a simple 

 proof of the anharmonic ratio of four faces in a zone. — Mr. 

 William Barlow, in continuation of his work on the partitioning 

 of space on the principles of closest packing, exhibited models 

 which presented accurately the symmetry displayed by potassium- 

 alum. The symmetry of various tetartohedral minerals was 

 also explained by the twist which must be given to certain 

 groups of atoms in order to make the paskingas close as possible. 

 — Mr. Herbert Smith, in continuation of an examination of 

 crystals of calaverite, showed by means ofagnomonic projection 

 the extremely intricate character of the crystals. The general 

 form suggests monoclinic symmetry, and a well developed face 

 perpendicular to the prism edge frequently occurs ; but the 

 symbols which on this supposition must be assigned to the faces 

 are, with few exceptions, very complicated. The majority of the 

 faces lie on a lattice with triclinic symmetry, and of the remain- 

 der the majority lie on another lattice inconsistent with the 

 former. — Mr. G. T. Prior pointed out the isomorphous 

 relations between sulphates and orthophosphates as exhibited 



