May 1 6, 1901] 



NATURE 



it had been prepared were now on their way home. There 

 could be no doubt that the animal was not an Equus, and 

 could not be placed satisfactorily in any known genus of recent 

 Mammals. — Dr. W. G. Ridewood exhibited and made re- 

 marks on a series of microscopic preparations of the hairs 

 of Antelopes, Giraffe, Zebra, and the so-called Eqittis johnstoni, 

 pointing out that the hairs of the last-named animal were 

 similar to those of the Giraft'e as well as those of the Zebra, 

 but diflferent from those of the Antelopes. — Mr. R. I. Pocock 

 communicated a paper, by Mr. G. W. Peckham and Mrs. 

 E. G. Peckham, on the spiders of the family Attidic found 

 in Jamaica, West Indies. It contained descriptions of thirteen 

 new species, of which one was made the type of a new 

 genus — Nilakantha. — Dr. David Sharp, F. R.S. , communicated 

 a paper by Mr. Peter Cameron, containing an ac- 

 count of the Hymenoptera collected during the "Skeat 

 E.xpedition " to the Malay Peninsula. Fifty-four species were 

 enumerated in the paper, of which thirty-one were described as 

 new. — Dr. David Sharp also commimicated a paper by Mons. 

 Eugene Simon on the Arachnida collected during the " Skeat 

 Expedition." It consisted of a list of the 131 species re- 

 presented in the collection and descriptions of forty-eight new 

 species and four new subspecies. 



Royal Astronomical Society, May 10. — Mr. Hinks ex- 

 hibited and described a new machine for measuring celestial 

 photographs, made for the Cambridge Observatory under his 

 superintendence, in the construction of which several improve- 

 ments had been effected. — Dr. Lockyer showed slides from 

 photographs of Nova Persei, and curves exhibiting its changes 

 of magnitude. — Father Sidgreaves gave further results of the 

 Stonyhurst observations of the spectrum of the Nova, which 

 distinctly varied with the variations of its light. — Father Cortie 

 read a paper on its visual spectrum, showing that the D lines 

 came out strongly at a minimum, and that the spectrum re- 

 sembled that of the solar chromosphere. — Prof. Turner com- 

 municated Mr. Bellamy's observations of the magnitude of the 

 Nova and the neighbouring stars. — Mr. Wickiham read the 

 observations for magnitude made at the Radcliffe Observatory, 

 Oxford, which supplemented and confirmed the observations 

 made at South Kensington. — A curve made by Mr. Child was 

 shown, exhibiting the variations in the brightness of the new star 

 from the time of its discovery. — Observations of magnitude by 

 Mr. Sharp and Mr. Stanley Williams were also read. — Father 

 Sidgreaves suggested an explanation of the fact that the dis- 

 placement of the lines in the spectra of new stars always 

 indicated a rapid motion of approach. — Prof. Turner read a 

 paper by Mr. H. C. Plummer on the geometry of the siderostat. 

 — A paper by Mr. Franklin Adams was read on an observation 

 of the " green flash " at sunset, a phenomenon which he 

 considered similar to that of "Baily's beads" seen during a 

 total solar eclipse. — Mr. Crommelin gave approximate elements 

 of the orbit of the new comet, from which it appeared that it is 

 moving rapidly from the sun and more slowly from the earth, 

 and that its brightness is rapidly diminishing. Although it 

 should shortly be visible in the evening sky it is improbable 

 that it will be a conspicuous object. 



Dublin. 

 Royal Irish Academy, May 13.— Prof. R. Atkinson, 

 president, in the chair.— Hipparchus and the precession of the 

 equinoxes, by Rev. M. H. Close. Hipparchus discovered the 

 increase of the longitudes of the fixed stars, which produces 

 the precession of the equinoxes, as we term it. That increase 

 might be due to (a) the eastward progression of the stars ; or to 

 (b) the westward retrogression of the equinoctial points, from 

 one of which the longitudes are reckoned ; or to (c) both these 

 movements existing together. We may dismiss c at once. Did 

 Hipparchus believe in a or in b ? Laplace, Lalande, and many 

 others declare that he believed in a ; Delambre, Bailly, and 

 many others that he believed in b. None give any arguments 

 for their opinions. Which are right ? The former, as would 

 appear thus; (i) Hipparchus admittedly shared the general 

 belief of his times in the immobility of the earth. He had 

 therefore a predisposition against b, which involves a movement 

 of the earth. (2) Ptolemy's treatment in the Almagest of 

 certain apparently (only) inconsistent expressions of Hipparchus 

 on the present subject shows that he (Ptolemy), who ought to 

 know, held that Hipparchus believed in the progression of the 

 stars. Besides which, we have, in two places in the same work, 



NO. 1646, VOL. 64] 



Ptolemy's direct statement to the same effect. (3) At' first, 

 when Hipparchus had examined only certain zodiacal stars, 

 and had observed their apparent progression, he supposed that 

 the extra-zodiacal stars did not participate therein. But he 

 cnuld not have supposed this had he believed in the retrogression 

 of the equinoctial points, for that would gi%'e an apparent 

 progression to all the stars. He found afterwards, however, 

 that the stars outside the zodiac preserved their positions rela- 

 tively to those within, which, from his above-mentioned pre- 

 disposition, would mean for him that all the stars progressed 

 together. 



Paris. 

 Academy of Sciences, May 6. — M. Fouqucin the chair. — 

 The influence of feeding, temperature, work and dust upon the 

 evolution of tuberculosis, by MM. Lannelongue, Achard and 

 Gaillard. \ series of guinea-pigs, artificially infected with 

 tuberculosis, were submitted to varying external conditions. If 

 compelled to do a certain amount of mechanical work each day, 

 the mortality increased with the amount of work done, those re- 

 maining at rest showing the most survivors. With insufficient 

 food the eflects were equally marked, those on full rations 

 having the best chance of survival. The inhalation of dust had 

 the same prejudicial effect as in man. — On the fourth volume 

 o( Ihe Aii/ia/es de V Ohscrvatoire dc Toulouse, by M. Lrewy. — 

 M. Zeuner was elected a correspondant for the section of 

 mechanics, and M. Oudenians a correspondant for the section 

 of geography and navigation in the place of the late M. de 

 Serpa Pinto. — The last sign of life ; its application to man, by 

 Dr. A. D. Waller. A modification of the method previously 

 described, but in which the skin remains intact. — The thermal 

 variations of waters, by M. F. A. Forel. The amplitude of 

 the annual thermal variation is a function of the latitude. The 

 depth of penetration of the heat is also a direct function of the 

 latitude, amounting to about 100 metres for the Lake of Geneva, 

 more than 1 50 metres for Loch Katrine, and more than 200 metres 

 for Lakes Mjosen and Ladoga. — Application of the wedge 

 photometer to the measurement of the photographic magnitudes 

 of the stars, by M. B. Baillaud. The method would appear 

 to give the most trustworthy results with stars of higher mag- 

 nitudes, the measurements with the more brilliant stars not 

 being so satisfactory. — Some new nebulce discovered at the 

 Observatory of Paris, by M. (1. Bigourdan. A list of new 

 nebulae, mostly fainter than thirteenth magnitude, together 

 with rectifications of the positions of some nebulae pre- 

 viously described. — On a particular class of ruled surfaces, by 

 M. A. Demoulin. — On the continuous deformation of sur- 

 faces, by M. G. Tzitzeica. — On Taylor's series, by M. L. Desaint. 

 — A practical method for the correction of the secondary error of 

 chronometers, by M. Ch. Ed. Guillaume. An application of 

 the properties of nickel steel to the more perfect temperature 

 compensation of chronometers. — On the existence of open cur- 

 rents, by M. V. Cremieu. As a consequence of the proof 

 previously given that electric convection produces no magnetic 

 effect, it follows that open currents ought to exist. Experi- 

 ments are now described verifying the existence of these. — On 

 osmosis through a membrane of copper ferrocyanide, by M. G. 

 Flusin. An experimental determination of the relation between 

 the osmotic pressure and the speed of osmosis. For solutions 

 of saccharose, amygdalin and antipyrine the observed pressures 

 agree satisfactorily with those calculated theoretically, none of 

 the substance passing through the membrane. With a i per 

 cent, solution of urea the observed pressure was far lower than 

 that calculated, and in this case it was found that urea had 

 passed through the membrane. The velocity of osmosis depends 

 upon the thickness of the membrane, but for a given porous pot 

 the velocities are proportional to the osmotic pressures, and hence 

 inversely proportional to the molecular weights. — On the 

 aluminium alloys. Combinations of aluminium with tungsten, 

 by M. Leon Guillet. By the reduction of tungstic anhydride 

 with an excess of aluminium a tungstide of aluminium can be 

 isolated in the crystalline state, po.ssessing the formula .AlW™. 

 — On an iodoantimonide of mercury, by M. Albert Granger. — 

 On a specimen of crystallised lime, by M. Ad. Jouve. In the 

 preparation of calcium carbide, if the mass be cooled at the 

 moment that the carbide commences to form, transparent 

 prismatic needles of lime are obtained. — On the chemistry of 

 methylene, by M. V. Thomas.— On the hydration of amylpro- 

 piolic acid with the formation of caproylacetic acid, by MM. 

 Ch. Moureu and R. Delange. Amylpropiolic acid cannot be 

 hydrolysed by sulphuric acid, but the reaction can be effected 



