96 



NATURE 



\_May 23, 1889 



advanced phase of their development. The photograph of this 

 nebula taken by Mr. Roberts reveals a planetary system, in 

 which some planets are already formed, and their central mass 

 -condensed. — On the surgical treatment of the foot in cases of 

 suppurated osteo-arthritis, by M. Oilier. Hitherto amputation 

 has generally been considered the only remedy ; but the author's 

 -experiments show that, by removal of the ankle with abrasion or 

 resection of the limiting articulations, the foot may be preserved 

 almost in its normal state and with little detriment to its loco- 

 motive functions. — On the linear expansion of solid bodies at 

 high temperatures, by M. Pionchon. These researches show that 

 by means of the simple process here described M. Fizeau's well- 

 4cnown experiments may be repeated with the greatest ease. 

 M. Pionchon now proposes to apply the process to the study of 

 the linear expansion of amorphous and crystallized solid bodies 

 ;it high temperatures. — On the direct measurement of the 

 retardation produced by the reflection of luminous waves, by M. 

 A. Potier. These experiments, which are applicable to a large 

 number of substances, constitute a method by means of which 

 the retai-dation may be directly measured, which is caused by the 

 reflection of the luminous waves on their surface. — On the 

 influence of terrestrial magnetism on atmospheric polarization, 

 by M. Henri Becquerel. In a previous memoir {Annales de 

 Chimie et de Physique, xix., 1880) the author showed that in a 

 cloudless sky the plane of polarization is not generally coincident 

 with the theoretic plane (plane of the sun), and further that the 

 two should coincide when the latter is vertical, but that, in a 

 region near the horizon and the magnetic meridian, the plane of 

 ■polarization then deviates by a small angle in the direction 

 corresponding to the rotation of the plane of polarization of a 

 luminous ray traversing a column of air, subject to the magnetic 

 influence of the earth. In the present paper he determines both 

 the direction and the extent of the rotation, and also shows how 

 this display of terrestrial magnetism is associated with some of 

 the most interesting questions connected with the physics of the 

 globe. — A study of the electric conductivity of saline solutions, 

 as applied to chemical mechanics — the acid salts, by M. P. 

 Chroustchofif. The author has applied M. Bouty's extremely 

 sensitive electrometric method of measuring the electric con- 

 ductivity of liquids to the study of several problems in 

 ohem.ical statics. In the present paper he tabulates the 

 chief measurements of the electric conductivity of aqueous 

 solutions containing one salt only. — Action of the atmo- 

 sphere on manganese carbonate, by M. A. Gorgeu. In this 

 paper the author discusses the question whether this action 

 can give rise to any of the natural dioxides, as assumed by 

 MM. Boussingault and Dieulafait. — Papers were contributed 

 by M. L. Pigeon, on platinic chloride ; by M. Aug. Lambert, 

 •on the action of borax on the polyhydric phenols and alcohols ; 

 and by M. H. Prouho, on the structure and metamorphosis of 

 Flustrella hispida. — -A c^py of M. Seligmann-Lui's translation 

 ■of Clerk Maxwell's classical treatise on " Electricity and Mag- 

 netism " was presented to the Academy by M. Sarrau. 



Berlin. 



Physical Society, April 26.— Prof. Kundt, President, in 

 the chair. — Prof. Kundt gave a short account of recent re- 

 searches on electro-magnetic rotatory polarization, and developed 

 the more general point of view froai which they had been 

 respectively undertaken. Since the time when Faraday disco- 

 vered the fundamental phenomena and later physicists had 

 accumulated a mass of material on which ob ervations could 

 be made, two facts had chiefly presented difficulties in con- 

 nection with the established theory : of these one was the 

 varying direction of rotation produced by different substances, 

 some producing a positive rotation (in the direction of the Am- 

 perian current), others a negative rotation ; the other fact was 

 the absence of magnetic rotation in doubly-refractive crystals. 

 Starting from some theoretical considerations, the speaker was 

 led to surmise that rotation is not wanting in these crystals, but 

 is only obscured by some opposing phenomenon, a view which 

 has been fully confirmed by experiments carried out at his sug- 

 gestion by Drs. Wedding, Wiener, and du Buis. When a piece 

 of glass was made doubly refractive by pressure, its magnetic 

 rotatory polarization diminished, becoming nil when the differ- 

 ence in path of the two rays was ^X ; when the difference was 

 ^A, then the rotation took place in the opposite direction. When 

 the difference was A., the rotation was again nil, and it varied 

 »hus in a wave-like manner, with increasingly small amplitudes 



until it ceased entirely. Prof. Kundt concluded from this that 

 the power of electro-magnetic rotatory polarization is common to 

 a// substances, whether crystalline or isotropous. As regards 

 the varying direction of rotation, his own experiments had shown 

 that simple substances produce a positive rotation, and com- 

 pound bodies a negative rotation ; this last result may be ex- 

 plained by the fact that the Amperian currents inside compound 

 bodies run in a direction different from that in the magnetic 

 field. The proportionality of rotation to the strength of mag- 

 netization is also a property common to all substances ; its rela- 

 tionship to ' refraction is being made the subject of further 

 researches. Dr. Koenig (from Leipzig) pointed out many 

 ana'ogies which exist between the electrical rays discovered by 

 Prof. Hertz and rays of light, more particularly the polarization 

 of the electrical rays by means of the wire grating and the phe- 

 nomena w hich may be observed in the immediate neighbour- 

 hood of the rays as they are advancing in straight lines, pheno- 

 mena which are in exact accord with those described by Stokes 

 in the case of light. 



Stockholm. 



Royal Academy of Sciences, April 9. — Researches on the 

 deviations of the plumb line in Sweden, by Prof. Rosen. — 

 Resume preliminaire d'une recherche experimentale sur I'ab- 

 sorption _^de la chaleur rayonnartte par les gaz atmospheriques, 

 by Dr. Angstrom. — Newly found specimens of Anser bracliy- 

 rhynchus, Baill., in Sweden, by Dr. A. Stuxberg. — On a singular 

 Tetrarhynchid larva, by Herr E. Lonnberg. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Eclectic Physical Geography : R. Hinman (Low). — A Treatise on the 

 Principles of Chemistry, 2nd edition: M. M. P. Muir (Cambridge Univer- 

 .sitv Press). — Teutonic Mythology : V. Rydberg, tran-Iaied by R. B. 

 Anderson (Sonnenschein). — Die E'ltstehung der Artendurch Raumliche Son- 

 derung : M. Wagner (Basel, B. Schwabe). — Examination of Water for 

 Sanitary and Technical PuiTioses: H. Leffmann and VV. Beam (Philadelphia, 

 HIakiston). — Hourly Readings, 1886, Part 3. July to September (Eyre and 

 Spottiswoode). — The Uses ot Plants : G. S. Bou'ger (Roper and Drowley). 

 — Journal of the Institution of Electrical Engineers, No. 79, vo'. xviii. (Spon). 

 — Quarterly Journal of the Geological Society, No. 178 (Longman.s). — 

 Ergebnisse der Meteorologischen Beobachtungen, Jahrg. x. (Hamburg). 



CONTENTS. PAGE 



The New Technical Education Bill 73 



A Text-Book of Human Physiology 74 



Geography in Germany. By H. J. Mackinder ... 75 

 Our Book Shelf.— 



Dickson: " Gleanings from Japan " ........ 76 



Greaves : " Statics for Beginners " 77 



Letters to the Editor-. — 



The Structure and Distribution of Coral Reefs. — Prof. 



T. G. Bonney, F.R.S 77 



The Turtle-headed Rock Cod.— T 77 



Atmospheric Electricity. — Dan. Pidgecn 77 



Rain-Clouds. — Dr. Julius Hann 78 



The Muybridge Photographs. By Prof. E. Ray Lan- 



kester, F.R.S 78 



On the Determination of Masses in Astronomy. By 



R. A. Gregory • 80 



A New Form of Regenerative Gas-Lamp. (Illus- 

 trated.) 82 



Heinrich Gustav Reichenbach 83 



Notes 84 



Astronomical Phenomena for the Week i38g 



May 26 — ^June i 86 



Beacon Lights and Fog Signals. I. {Illustrated.) 



By Sir James N. Douglass, F.R.S 87 



A Bill to Provide Technical Education in England 



and Wales 91 



Scientific Serials 91 



Societies and Academies 92 



Books, Pamphlets, and Serials Received 96 



