384 



NATURE 



[February 20, 1896 



with sodium amalgam in acid solutions gives the lactone cam- 

 pholide, CjrtHigOj, not identical with the substance of the same 

 composition obtained by Dr. M. O. Foster {J. C. S. , January 

 1896). — Copernicus and the geographical discoveries of his time, 

 by M. Daubree. — On the equation of the tides, by M. Maurice 

 d'Ocagne. — On surfaces of lines of spherical curvature, 

 by M. E. Blutel. — On a generalisation of the formula 

 for the area of a spherical triangle, by M. X. Stoufif. — 

 Note on the resistance of beams, by M. Paul Toulon. — Method 

 of measuring double refraction in monochromatic light, by 

 M. R. Dongier. — Influence of the chemical nature of substances 

 on their transparency to the Rontgen rays, by M. Maurice 

 Meslans. Compounds of carbon, hydrogen, oxygen, and 

 nitrogen are very nearly transparent for these rays, but the 

 introduction of phosphorus, sulphur, or the halogens (especially 

 iodine) largely increases their opacity. — Application of the 

 method of M. Rontgen, by M. A. Londe. The dark and light 

 parts of a photographic negative are equally transparent to the 

 rays.— Increase of the photographic effect of the Rontgen rays 

 by phosphorescent zinc sulphide, by M. C. Henry. It was 

 found that by coating coins opaque to the rays with phos- 

 phorescent sulphide of zinc, photographic impressions of sub- 

 stances beneath the coins could be obtained, metals coated in 

 this manner appearing to lose their opacity to the Rontgen 

 rays. — Photographs obtained by means of the X-rays, by 

 M. C. V. Zenger. — On a mechanical action proceeding from a 

 Crookes' tube, analogous to the photogenic action discovered 

 by Rontgen, by MM. Gossart and Chevallier. In attempting 

 to show the heating effect of a Crookes' tube by means of a 

 radiometer, it was found that the latter, instead of rotating, took 

 up a fixed position under the control of the tube. If the radio- 

 meter arms were set in motion by heat, oscillations about this 

 fixed direction ensued, which were the more rapid the smaller 

 the distance between the tube and the radiometer. This force 

 was stopped by the same media as the X-rays.— On the silicide 

 of copper, by M. Vigouroux. Silicon and copper, heated in the 

 electric furnace, give homogeneous products which may contain 

 silicon up to 15 per cent. Prolonged heating at a temperature 

 sufficiently high to drive off excess of copper, leaves the definite 

 compound SiCu.,. — On the bromide and chlorobromide of 

 thionyl, by M. A. Besson. Dry HBr, acting on SOCI.2 at its 

 boiling-point, gives rise to a mixture from which SOClBr, 

 SOBrj, and S.2Br2, which can be separated by fractional distilla- 

 tion under reduced pressure. Thionyl bromide is not formed by 

 the action of sulphur dioxide upon phosphorus pentabromide. — 

 On a crystallised sulpho-phosphide of tin, by M. A. Granger. 

 Tin sulphide, acted upon by phosphorus vapour, gives the 

 compound SnP. 2SnS. — Oxyiodides of zinc, by M. Tassily. — 

 Method for determining the purity of butter by means of the 

 density, by M. R. Brulle. — Retineal stroboscopy, by M. Aug. 

 Charpentier. — The expulsion of blood as a means of defence 

 in some Sauterelles, by M. E. Cuenot.— On the frontal expan- 

 sion of some insects of the family of the Muscides, by M. J. K. 

 d'Herbulais. A criticism of a note on a recent communication 

 on the same subject by M. A. Labboulbene. — On the significa- 

 tion of the fertilisation in the Uredineoe, by M. Sappin-Trouffy. 

 — On the sugars produced in leaves, by M. G. Bonnier. It 

 is shown that in many cases these sweet liquids are directly 

 exuded frorn the stomata of the leaf, and are not always of 

 animal origin. The rate of production of this vegetable honey 

 is at a maximum during the night. — Mucor and Tricho- 

 derma, by M. J. Ray. Reply to a criticism of M. 

 Paul Vuillemin. — The Hippurite bearing layers in the 

 Valley of the Rhone, by M. H. Douville.— On the 

 existence of numerous Radiolaria in the Ardeche, by M. 

 L. Cayeux.— On the mode of formation of the auriferous 

 minerals of the Witwatersrand in the Transvaal, by M. L. de 

 Launay. The hypothesis of a chemical precipitation of the gold 

 and pyrites during the actual sedimentation is shown to be the 

 most probable.— On a hypothetical mode of formation of the 

 auriferous conglomerates of the Transvaal, by M. E. Cumenge. 

 — On some new and rare forms of calcite at Couzon (Rhone), by 

 M. F. Gonnard.— On the high atmospheric pressures during the 

 month of January 1896, by M. P. Dechevrens. 



Berlin. 



Physical Society, January 17.— Prof, du Bois Reymond, 



President, in the chair. — Dr. Frolich spoke on the protection of 



physical laboratories from the effects due to electric tram-lines, 



and described the arrangement used by Siemens and Halske. 



NO. 1373, VOL. 53] 



This consists of two coils of wire-netting at right angles to each 

 other, which being stretched round a wooden frame, and 

 surrounding the instrument it is desired to protect, are put into 

 metallic contact by a cable with the conducting rail of the tram- 

 line. The disturbance due to the passage of a car is thus com- 

 pensated, and the effect on a magnetised needle is reduced to a 

 small percentage. 



January 3i.^Prof. du Bois Reymond, President, in the chair. 

 — Dr. Kaufmann gave an elaborate demonstration of Rontgen's 

 X-rays. He also exhibited a very striking photograph of a. 

 mouse, which showed in detail the separate vertebrae of the tail, 

 the ribs, and other bones. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Books. — Chemistry for Engineers and Manufacturers : B. Blount and A. 

 G. Bloxam, Vol. i (Griffin). — A New Natural Theology based upon the 

 Doctrine of Evolution : Rev. J. Morris (Rivington). — Universal Electrical 

 Directory (Alabaster). — Geology : C. L. Barnes (Rivington). — Lite and 

 Exploits of Alexander the Great : Dr. E. A. W. Budge (Clay).— Grundriss 

 der Krystallographie fiir Studirende und zum Selbstunterricht : Dr. G. 

 Linck (Jena, Fischer).— Traite des Matieres Colorantes : L. Lefevre, 2 Vols. 

 (Paris, Massony—Ii/ecirician Electrical Trades' Directory and Handbook 

 for i^q(> {Electrician Company). 



Pamphlets. — Report of S. P. Langley, Secretary of the Smithsonian Insti- 

 tution, for the Year ending June 30, 1895 (Washington). — Classification 

 Chart of the Commoner British Orders of Flowering Plants : W. P. Winter 

 (Cheltenham). — tiber Germinal-Selection eine quelle Bestimmt Gerichteter 

 Variation : A. Weismann (Jena, Fischer). 



Sekials. — Journal of the Franklin Institute, February (Philadelphia). — 

 American Naturalist, February (Philadelphia). — Journal of the Chemical 

 Society, February (Gurney). — The Asclepiad, Vol. 44, Vol. xi. (Longmans). 

 — Proceedings of the Physical Society of London, Vol. 14, Part 2 (Taylor). 

 — Journal of the Institution of Electrical Engineers. No. 119, Vol. xxiv. 

 (Spon). — Internationales Archiv fiir Ethncgraphie. Band ix. Heft i (Leiden, 

 Brill). — Astrophysical Journal, February (Wesley). — Strand Magazine, 

 February (Newnes). 



CONTENTS. PAGE 



Embryology 361 



The Evolution of Cultivated Plants. By Dr. Max- 

 well T. Masters, F.R.S 363 



Our Book Shelf:— 



Hahn : " Die Haustiere und ihre Beziehungen zur 



Wirtschaft des Menschen " 364 



Letters to the Editor: — 



Velocity of Propagation of Electrostatic P"orce. — Prof. 



A. H, Leahy; Lord Kelvin, F.R.S 364 



The Stress in Magnetised Iron. — Dr. C. Chree . . . 365 

 Experiments with Soaring Machines. {Illustrated.) — 



Percy S. Pilcher 365 



Science and Morals. — Prof. William Ramsay, 



F.R.S 366 



The Former Northward Extension of the Antarctic 



Continent.— Theo. Gill 366 



Children's Drawings. — A. B. M 366 



Lecture Experiment on the Nodes of a Bell. — H. G. 



Williams 367 



The Planet Venus. {Illustrated.) By W. J. S. L. . 367 

 The Seebohm Collection. By Dr. R. Bowdler 



Sharpe 369 



Movement. {Illustrated.) By F. J. S 370 



The New Muzzling Order 371 



Notes 372 



Our Astronomical Column: — 



Perrine's Comet 376 



A New Comet 376 



The Zodiacal Light 376 



Surface Drift of Jupiter 376 



The Temperature of Air and the Problem of an Ice 



Age. By Dr. Luigi De Marchi 376 



The Rontgen Rays 377 



The Manufacture of Aluminium by Electrolysis . . 380 



University and Educational Intelligence 380 



Scientific Serials 381 



Societies and Academies 382 



Books, Pamphlets, and Serials Received 384 



