NA TURE 



\_Nov. i8, i! 



scope, seen in clouds small, round bodies moving up and down, 

 which he had taken for rain-drops, aud commende;! to those 

 interested in the study of the atmosphere such observations o( 

 clouds. Respecting the possibility of seeing the rain-drops of 

 clouds in this manner there arose a lengthy discussion. 



Physical Society, November 4. — Prof, von Helmholtz in 

 the chair. — Prof. Sporer produced and made the subject of 

 discussion a long series of heliographic maps which he had 

 drawn from phenomena he had himself witnessed, and which 

 demonstrated in a very graphic manner the occasionally very 

 important proper motions of different spots. These self 

 movements always occurred on the west side of the spots, and 

 of the groups of spots. They always followed therefore in the 

 sense of the sun's rotation. They were recognised when the 

 spots were observed several times in the course of a day, and 

 they sometimes attained values of from 1000 to 2000 geo- 

 graphical miles in one day. These movements were specially 

 intense in the case of the formation of larger spot-groups ; 

 later on they grew slower. For the explanation of these proper 

 motions, the speaker adduced that sunspots invariably formed 

 themselves only over luminous surfaces, that is, at spots of the 

 solar surface possessing a higher temperature. In his measure- 

 ments of temperature, which had not yet been published, having 

 reference to the year 18S0, he made use of a thermo-element on 

 which, through a fine opening in a thick pasteboard disk, he 

 caused to fall the position of the sun's image which he wanted 

 to measure. According to these observations, the emission of 

 heat from a spot-umbra stood to the radiation of heat from a 

 luminous surface as 10 : 18, and the radiation of a spot-umbra 

 to the radiation of the usual solar surface as 10 : 15. Seeing 

 that the temperatures on the sun stood probably in the same 

 relation as did the radiations, so in the luminous surfaces which 

 possessed a higher temperature (in the relation of 6 : 5) must an 

 ascending gas-current develop, to which a descent of colder gas- 

 masses must necessarily correspond. These descending colder 

 gases it was which generated the spots, and gave them — seeing 

 they possessed a greater linear speed of rotation than did the 

 solar surface — a displacement towards the west in the sense of 

 the rotation. — Dr. Pernet spoke on the determination of the air 

 in the vacuum of the barometer, in accordance with the Arago 

 method, connecting his observations with a publication by Dr. 

 Schreiber, who, on comp.aring the barometer of the Saxon 

 station with the normal barometer, found, after taking due 

 account of all corrections in the latter, volumes of air far sur- 

 passing the permissible quantities. Dr. Pernet had now found 

 that two very essential corrections were overlooked : first, the 

 determinations of the air in vacuum under the pressures o, 40, 

 and 80 millimetres, were carried out in much too rapid suc- 

 cession, so that compensations of temperature were impossible ; 

 second, the effect of the capillarity was not observed, an effect 

 which in the case of syphon barometers played so far a great 

 part, as the lower surface of the quicksilver affected by oxidation 

 and dust had a different surface-tension and different angles 

 of rim from the upper surface of the quicksilver, which was 

 comparatively pure. The registrations were therefore not exact 

 if the menisci were not simultaneously measured. This tension 

 of the surface was in the case of thermometers also very im- 

 portant. In consequence of it, the readings of thermometers 

 with narrow tube and less mass of quicksilver were less exact 

 than the readings of thermometers with wider tube and more 

 quicksilver. It was the cause that thermometers with elliptic 

 tubes were less exact than thermometers with circular ones. 

 The effect of the capillarity, again, was, in the opinion of the 

 speaker, the cause of the "dead point" of Mr. Pickering. 



Vienna 



Imperial Academy of Sciences, October 7. — On Hall's 

 phenomenon, by A. von Ettingshausen and W. Nernst. — On 

 the data wanted for proving Avogadro's law, by L. Boltz- 

 mann. — On the theory of the electro-magnetic phenomenon 

 discovered by Hall, by the same. — On the density of liquefied 

 methene and liquefied oxygen, by K. Olszewski. — On the 

 comets discovered by Mr. Finlay on September 26, and by 

 Dr. Hartwig on October 6, by E. Weiss.— On colchicine, by 

 S. Zeisel. — Contributions to the knowledge of the Tertiary flora 

 of Australia, second paper, by C. von Ettingshausen. 



October 14. — Researches on strychnine, especially on the 

 action of zinc-dust on strychnine, by W. F. Loebisch and P. 

 Sclioop. — A jireliminary communication on the statist.'Cs of 

 comets, by T. Unterweger. 



October 21. — To histology and physiology of mucous secre- 

 tion, by W. Biedermann. — Remarks on L. Hermann's galvano- 

 tropic experiment, by E. Mach. — On hydrocarotin and carotin, 

 by F. Reinitzer. — On the anatomy and systematics of gall-mites, 

 by A. Nalepa. 



BOOKS AND PAMPHLETS RECEIVED 



Encyklopaedia der Naturwissenschaften, Erste Ablheil., 48.49 Lief. ; Zweite 

 Abtheil., 37-38 Lief. (Trewendt, Breslau).— Index Catalogue of the Library of 

 the Surgeon-General's Office, U.S. Army, vol. vli. (Washington). — Proceed- 

 ings of the Linnean Society of New South Wales. 2nd series, vol. i., part 2 

 (Cunningham, Sydney). — Quarterly Journal of Microscopical Science, Oc- 

 tober (Churchill).— .\lpine Winter, 3rd edition : Dr. A. T. Wise (Churchill). 

 — Encyclopaedia Britannica, vol. xxi. (Black, Edinburgh). — Structure and 

 Life-Histoi-y of the Cockroach ; L. Miall and A. Denny (L. Reeve). — Mada- 

 gascar, 2 vols. : Capt. S. P. Oliver (Macmillan). — Journal of the Anthropo- 

 logical Institute, November (Triibner). — First Year of Scientific Knowledge, 

 3rd edition : P. Bert (Relfe).— Nouvel Atlas Celeste : R. A. Proctor ; trans- 

 lated into French by P. Gerigny (Gauthier-Villars, jParis).— Ordnance 

 Survey of the United Kingdom : Lieut. -Col. White (Blackwood). — La 

 Photographic sans Objectif : R. Colson (Gauthier-Villars, Paris).— L' Aurora 

 Bor<£ale: M. S. LemstrOm (Gauthier-Vilbrs, Paris).— Les Hypotheses 

 Cosmogoniques : Examen des Theories Scientifiques Modernes sur I'Origine 

 des Mondes, suivi de la Traduction de la The'oriedu Ciel de K.TOt : C. Wolf 

 (Gauthier-Villars, Paris).— Hand-book of Jamaica for 1886-87 : A. C. 

 Sinclair and L. R. Fyfe (Stanford) —Quarte.-ly Journal of the Royal 

 ^^eteorologicaI Society, October (Stanford).— Monthly Results of Observa- 

 tions made at the Stations of the Royal Meteorological Society, vol. vi., 

 No. 22 (Stanford), 



CONTENTS PAGE 

 The Zoological Results of the "Challenger" Expe- 

 dition 49 



Elementary Dynamics 51 



Our Book Shelf:— 



Church's "Food-Grains of India."— Prof. John 



Wrightson 5' 



Taylor's "Tobacco a Farmer's Crop." — Prof. John 



Wrightson 52 



Marion's " Practical Guide to Photography " .... 52 

 Bird's " Lecture-Notes and Problems on Sound, Light, 



and Heat " 52 



Griffin's " Bicycles and Tricycles for the Year 1886" 52 

 Letters to the Editor : — 



Extension of the Corona. — Prof. S. P. Langley . . 52 

 The Astronomical Theory of the Great Ice Age. — 



Sir Robert S. Ball, F.R.S 53 



Abnormality in Cats' Paws. — ^J. Herbert Hodd . . 53 

 Abnormalities in the Vertebral Coluinn of the Common 



Frog.— Prof. C. Lloyd Morgan 53 



Influence of Wind on Barometric Readings. — G. J. 



Symons, F.R.S 53 



Barnard's Comet. — T. W. Backhouse 54 



Aurora. — Dr. M. A. Veeder 54 



"Lung Sick." — Philip J. Butler 54 



Paul Bert 54 



The Recent Weather. By Rev. W. Clement Ley . 54 



The Work of the United States Fish Commission . 55 

 Volcanic Dust from New Zealand. By Prof. T. G. 



Bonney, F.R.S 56 



Notes 57 



Our Astronomical Column : — 



The Influence of Astigmatism in the Eye on Astro- 

 nomical Observations 59 



The Kalocsa Observatory 59 



(T Cassiopeije 59 



New Minor Planets 59 



Comet Finlay 59 



Comet Barnard 59 



Gould's Astronomical Journal 59 



Astronomical Phenomena for the Week 1886 



November 21-27 59 



Geographical Notes 60 



Lighthouse lUuminants, II. By A. Vernon Har- 



court, F.R.S. ; and T. and D. Stevenson 60 



Official Report on the Use of Oil at Sea for modify- 

 ing the Effect of Breaking Waves 63 



On the Intensity of Reflection from Glass and other 



Surfaces. By Lord Rayleigh, F.R.S 64 



On the Nature of Solution 64 



Ten Years' Progress in Astronomy. By Prof. C. A. 



Young 67 



University and Educational Intelligence 69 



Societies and Academies 70 



Books and Pamphlets Received 72 



