456 



NA TURE 



[September io, 1896 



it "parhelium" (Pa) and assigns to it an atomic weight of 

 about 3. — Distance action of the force of absorption, by 

 W. Miiller-Erzbach. The author claims to have proved that 

 the absorptive force exercised, say, by iron oxide upon carlion 

 bisulphide vapour is capable of acting across a thin layer of a 

 substance like water or glycerine which is perfectly neutral 

 itself. This molecular force is, unlike that of ordinary 

 molecular attraction, capable of action at distances not 

 exceeding 0-0025 ™"i- across intervening bodies. — Rontgen 

 rays, by Otto Miiller. In the course of an attempt to produce 

 diffraction of X-rays, a shadowgraph of wire gauze was obtained 

 under a metallic cylinder which screened the plate from the 

 action of the rays. The distance between cylinder and plate 

 was 20 cm. The author interprets the observation as a proof of 

 the turbidity of the air to some at least of the X-rays, and 

 ascribes the effect to diffusion. 



Bolkttino della SocietH Sismologica Italiana, vol. ii., 1896, 

 No. 2. — New methods for geodynamical investigations, by G. 

 Grablovitz. A valuable description of the instruments erected 

 in the geodynamic observatories of the island of Ischia, includ- 

 ing various forms of levels, horizontal pendulums, instruments 

 for measuring the vertical movements of the ground, and 

 seismoscopes. — New form of continuously recording seismo- 

 metrograph, by A. Cancani. — On the so-called presentiment of 

 earthquakes by animals, by A. Cancani. — On some facts resulting 

 from microseismic observations, by G. Vicentini. A reprint of 

 a paper already noticed in Nature. 



SOCIETIES AND ACADEMIES. 



Paris. 

 Academy of Sciences, August 31.— M. A. Chatin in the 

 chair. — The Perpetual Secretary announced the death of M. 

 Henri Resal, member of the Section of Mechanics. — On the 

 subject of prime numbers, of which any given number cannot 

 be a primitive root, by M. de Jonquieres. — External characters 

 and modes of distribution of the small tubercles or tuberculoids 

 of the LeguminosK, by M. D. Clos. A morphological study of 

 the tuberculoids on the roots of nine sub-species of the Papi- 

 lionaciv. In the two other groups of the Leguminos;e Ccesal- 

 piniiie and the Mimosae, the presence of the tubercles is by no 

 means so frequent as in the Papilionacre. — Memoir on the Law 

 of Newton and on some problems in general mechanics, by 

 M. E. La Combe. — On the effect of systematic errors in level- 

 lings of precision, by M. Ch. Lallemand. It is shown that, 

 with a few exceptions, levellings of precision are subject to 

 systematic errors, which may vary from 05 mm. to 03 mm per 

 kilometre, and hence are of more importance than the accidental 

 errors to which, up to now, attention has been chiefly directed. 

 It has not been found possible to connect these systematic errors 

 with the particular instruments employed, with the observers, 

 with the nature of the ground, or with the atmospheric condi- 

 tions. — On a class of propositions analogous to the Miquel- 

 Clifford theorem, by M. Paul Serret.— The deflection of the 

 X-rays behind opaque bodies, by M. E. Villari. A gold-leaf 

 electroscope, placed in the cone of shadow of a sheet of lead, 

 was found to be discharged by the X-rays at rates which 

 showed that the shadow was deepest at the centre. — 

 Researches on the double chlorides, by .M. R. Varet. Athermo- 

 chemical study of the double chlorides . formed by mercuric 

 chloride with other chlorides. — Action of the soluble oxidising 

 ferment from mushrooms on the phenols insoluble in water, by 

 M. E. Bourquelot. The two naphthols are oxidised by this 

 ferment in a manner that may serve to distinguish them, 

 a-naphthol giving a violet colouration, ;8-naphthol a white 

 precipitate, which dissolves to a yellow solution in ether. — On 

 the freezing-point of milk, by MM. Bordas and G^nin. Fifty 

 samples of milk gave freezing points varying from - o°'44 C. to 

 - o"'56 C, and the conclusion is drawn that the determination of 

 dilution with water by cryoscopy is neither simple nor certain. — 

 On the organisms causing disease of the silk-worm, by M. J. 

 M. Krassilschtschik. — A telegraph cable attacked by Termites, 

 by M. E. L. Bouvier. — On the secretory nerves of the trachea, 

 by M. V. Thebault. — On the conjugation of the zoospores of 

 Ectocarpiis silictilosus, by M. C. Sauvageau. — On the velocity 

 of sound, by M. G. W. Pierces.— On the resolution ot the 

 general equation of the fifth degree, by M. L. Mirinny. — On the 

 geographical situation of submarine islands, by M. Keilly. 



NO. 1402, VOL. 54] 



GtlTTINGEN. 



Royal Society of Sciences,— The Nachruhten, Part 2 

 (Mathematico-Physical Section), 1896, contains the following 

 memoirs communicated to the Society : — 



April 25. — On the theory of automorphic modular groups, by 

 R. Fricke.— On an optical effect of an electric field conditioner! 

 by the dependence of the dielectric coefiicients on the strength 

 of the field, regarded from the .standpoint of the electro- 

 magnetic theory of light, by E. Pockels. 



May 9. — Researches from the Giitlingen University Labora- 

 tory (IV.), by O. Wallach. (i) Condensation-products of cyclic 

 ketones, and syntheses within the terpene group ; (2) a bicyclic 

 ketone CijIL^O ; (3) benzylidenemethyihexanone Cylli.iO : 

 CUCbHj ; (4^ dibenzylidene-methylhexanone Q^MjZW : C^HgO: 

 CHCgHj ; (5) benzylidene-menthone ; (6) benzylidene pulegone ; 

 (7) dibenzylidene-suberone CoHjCH : (CrHgO) :CHC„H, ; (8) 

 dibenzylidene-methylpentanone C„HsCH : CsHsO : CHC„H6.— 

 On the principles of Hamilton and Maupertuis, by O. Holder. 



June 20. — Attempted demonstration of orientation in the sur- 

 face-conduction of electricity ; on the continuous transition of 

 an electrical property through the boundary- layer between solid 

 and fluid bodies ; ' on the conduction of electrified air ; an 

 experiment on magnetic currents, each by Ferdinand Braun. 



July 4. — A contribution to the theory of complex magnitudes 

 consisting of « primary units, by David Hilbert. 



July 18. — Fluorescence and the kinetic theory, by W. Voigt. 

 — On the change in the mode of vibration of light in passing 

 through a dispersing or absorbing medium, by W. Voigt. 



BOOKS AND SERIALS RECEIVED. 



Books.— Outlines of Psychology : E. B. Titchener (Macmillan).— Baby- 

 loni.in Magic and Sorcery: L. W. King (Luzac). — By the Deep Sea . E. 

 Step (Jarrold). — British Association, Liverpool. 1S96. E.vcursion Guide- 

 book (Liverpool, Philip). — A Diction.iry of the Economic Products of 

 India. Index (Calcutta).— The Book of the Dairy: Dr. W, Fleischmann, 

 translated by C. M. Aikman and R. P. Wright (Blackie).- Element.ary 

 Quantitative Chemical Analysis: Dr. F. Clowes and J. B. Coleman 

 (Churchill).— Lehrbuch der Algebra : Prof H. Weber, i. Band (Braun- 

 schweig, Vieweg). 



Seki.\ls.— Geological Magazine, September (Dulau). — Geographical 

 Journal, September (Stanford). — Edinburgh Medical Journal, September 

 (Pentland). 



CONTENTS. PAGE 



Recent Ornithology 433 



British Mosses. By E. F 434 



Our Book Shelf:— 



Wulp : " Catalogue of the Described Diptera from 



South Asia."— W. F. K 435 



Smith : " History of Modern Mathematics " . . . . 435 



Barker: " Graphical Calculus. '' — G 435 



Letters to the Editor: — 



The Utility of Specific Characters. — W.T.Thiselton- 



Dyer, C.M.G., F.R.S 435 



Thermometer Readings during the Eclipse. ( With 



/)M4Taw.)—H. Wollaston Blake, F.R.S. . . . 436 



Sailing Flight. — Dr. R. von Lendenfeld 436 



The Conway Expedition to Spitzbergen. By Dr. 



J. W. Gregory 437 



The Last Day and Year of the Century : Remarks 



on Time-reckoning. By W. T. Lynn . ... 43S 

 Popular Geology. (Willi Diagram.) By Dr. Maria 



M. Ogilvie 439 



The Total Eclipse of the Sun. III. (Illustraled.) By 



J. Norman Lockyer, C.B., F.R.S 441 



Notes 445 



Our Astronomical Column: — 



New Comet 44S 



Comet Brooks (1896) 44S 



Telegrams to Astroiiomischen Nachrichten, No. 3376]. 448 



The Pleiades 449 



Meteors transiting the Solar and Lunar Discs .... 449 



The Great Seismic Wave of Japan 449 



The American Association Meeting, 1896 450 



Application of Rontgen Rays to the Soft Tissues 



of the Body. (Illitilralcd.) By Dr. John Macintyre 451 



Science in the Magazines 454 



University and Educational Intelligence 454 



Scientific Serials 455 



Societies and Academies 456 



Books and Serials Received 450 



