144 



NATURE 



[ytme 9, 1887 



never exceed 2^ knots, and that this velocity will be reached 

 only for a few hours at the equinoctial syzygies every year. It 

 is incidentally stated that the Canal will be 72 kilometres long, 

 21 metres wide at bottom, with a slope of 45°, and a depth of 

 1 1 '50 metres below the mean level at Panama, and of 9 metres 

 below that of Colon. — Observations of Barnard's Comet (1887 e) 

 made at the Algiers Observatory with the 0-50 m. telescope, 

 by MM. Trepied and Rambaud. These observations give, in 

 tabulated form, the apparent right ascension, the declination, 

 and number of comparisons with other stars for the period from 

 May 16 to May 24 ; also the positions of the stars and the 

 apparent positions of the comet for the same period. — On simul- 

 taneous linear equations with partial derivatives of the second 

 order, by M. Painleve. Some remarks are offered in connexion 

 with M. Goursat's recent paper on this subject, including the 

 explanation of a different method for obtaining the same results. 

 — On a melograph, by M. J. Charpentier. The apparatus 

 here described and presented to the Academy have been 

 devised and constructed for the purpose of offering a solution of 

 the problem relating to the fixation of musical improvisations, 

 and are applicable to the piano type of instruments. — On the 

 vapour-tensions of liquid cyanogen, by MM. J. Chappuis and 

 Ch. Riviere. While studying the compressibility of cyanogen 

 the authors have had occasion to measure some maxima tensions 

 of this gas, with results differing considerably from those obtained 

 by Faraday and Bunsen. The discrepancies are attributed jiartly 

 to the great difficulty of introducing cyanogen free from nitre 

 into the barometric chamber ; but chiefly to the manometric 

 methods employed by those physicists, these methods being much 

 inferior in accuracy to the open air manometer adopted by the 

 authors. — On the reproduction of a carbonate of soda known as 

 urao and trona, by M. Paul de Mondesir, These remarks are 

 intended to throw some light on the subject of sesquicarbonate 

 of soda, under which title are grouped various more or less un- 

 satisfactory data and observations. — Action of selenious acid on 

 the bioxide of manganese, by M. P. Laugier. During the 

 course of his researches to discover an oxygenated product 

 ScgOg corresponding to S2O5, obtained by the action of sul- 

 phurous acid on the bioxide of manganese, the author has obtained 

 some new compound^, here described, resulting from the com- 

 bination of selenious acid with the sesquioxide of manganese. — 

 On a simplified calcimeter, by M. A. Bernard. For the apparatus 

 here described it is claimed that it possesses several advantages 

 over that of Scheibler, although based on the same principle. — 

 Researches on the relations existing between the spectrum of the 

 elements of inorganic substances and their biological action, by 

 Mr. James Blake. The author's further researches with over 

 forty inorganic elements confirm his previous conclusions ; all 

 except nitrogen and potassium showing a definite relation between 

 their biological action and their conditions of isomorphism. 



Berlin. 



Physical Society, May 20.— Prof. Du Bois-Reymond, 

 President, in the chair. — Dr. Gross spoke on the electrical 

 condition of magnets during their magnetization. His experi- 

 ments were made with Joule magnets. A cylindrical piece of 

 iron was split along its axis, and the lower half of the cylinder 

 surrounded lengthways by the spiral wire which conveyed the 

 magnetizing current, completely insulated from it ; the ends of 

 the upper half of the cylinder were perforated by copper spikes, 

 which were then connected by means of copper wires with a 

 galvanometer so as to form a closed circuit. After this circuit, 

 which included the upper half-cylinder, had been brought into 

 electrical equilibrium, the magnetizing current (in the spiral 

 surrounding the other half of the cylinder) was reversed, and the 

 galvanometer gave a throw. The direction of the current thus 

 indicated was always opposite to that of the magnetizing current 

 passing along the inner surface of the half-cylinder. The speaker 

 thought himself justified in excluding the possibility of this result 

 being due to a simple inductive action of the magnetizing current 

 on the galvanometer circuit, inasmuch as when the iron half- 

 cylinder was replaced by one of copper the galvanometer then 

 gave no throw. (In the discussion which followed it was re- 

 marked, in opposition to this view, that the resistance of the 

 galvanometer was too great to admit of its indicating a simple 

 induced current when experimenting with the copper half- 

 cylinder.) Similarly, Dr. Gross is inclined to exclude as an 

 explanation any induction of the magnet upon itself, and thinks 

 that the cause of the current is the difference of potential between 

 the inner and outer side of the cylindrical magnet. This point 



he proposes to investigate carefully in a future series of experi- 

 ments. — Prof. Lampe criticised two papers which appeared last 

 year in the Reperloriiim fiir Fhysik, of which one contained 

 an explanation of gravitation, the other treated of the motion of 

 a Foucault pendulum. The speaker pointed out very fully the 

 mathematical and physical mistakes which had made it possible 

 for the author of the first paper to regard gravitation as due to 

 the rotation of the earth. — Prof, von Bezold gave an extremely 

 lucid description of Sprung's balance-barograph. — Prof. C. W, 

 Vogel communicated the most recent discovery in connexion 

 with instantaneous photography, by which it is now possible to 

 obtain instantaneous photographs not only at night but also in 

 the darkest places. Messrs. Goedicke and Miethe have prepared 

 a mixture of pulverized magnesium, chlorate of po:ash, and 

 sulphide of antimony, which when ignited produces an explosive 

 lightning-like illumination of such intensity that by means of it 

 an instantaneous photograph can be taken. The speaker then 

 gave a demonstration of the discovery by taking photographs of 

 several persons present ; he used the artificial light, of which 

 each flash lasted one-fortieth of a second, and in a few minutes 

 produced a picture during the meeting. The powders, as pre- 

 pared by the discoverers, cost only a few jDfennigs each, and will 

 hence readily come into general use.j 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Papers and Proceedings of the Royal Society of Tasmania for i386.— Guide 

 to the Science of Photo-Micrography : E. C. Bousfield (Kent). — Questions 

 on Physics : S. Young (Rivingtons). — Encyklopaedie der Naturwissen- 

 schaften, Erste Abth. 51 Lief, Zweite Abth. 42 and 43 Lief. (Trewendt, 

 Breslaii). — Elements of Phys'ological Psychology : G. T. Ladd(Longm.-ins). 

 — Les Pigmees ; A. de Quatrefages (Bailliere, Paris). — Official Record, New 

 Zealand Industrial E.xhibition. 1885.— Report of the Metropolitan Board 

 of Works, 1886.— British Dogs, No. 7 : H. Dalzlel (Gill).— Bees and 

 Bee-keeping, vol. ii. Part 8 : F. R. Cheshire (Gill).— Reports of Experi- 

 ments with various Insecticide Substances (Washington). — Our Shade- 

 Trees : C. V. Riley (Washington). — Bulletin of the Iowa Agricultural Col- 

 lege, November 1886 (Iowa). — Report of the Felsted Scho d Natural History 

 Society, 1886.— Diseases of the Hair, &c. : J. Startin (Harrison). — Inter- 

 national Journal of the Medical Sciences. April (Cassell). — Journal of the 

 College of Science, Imperial University, Japan, vol. i. Part 2 (Tokyo). 



CONTENTS. PAGE 



The Zoological Results of the Challenger Expedition 121 



A Grrman Treatise on the Vegetable Kingdom . . 123 

 Our Book Shelf :— 



Ridgeway : "Nomenclature of Colours for Naturalists " 124 



Beale : " English Tobacco Culture " 124 



Bettany : " Life of Charles Darwin" 124 



Letters to the Editor : — 



Thought without Words. — Colonel H. Stuart Wort- 

 ley ; Harold Picton 124 



Diatoms in the Thames. — W. H. Shrubsole , . . 125 



The Structure of the Nostochineee. — ^Walter Gardiner 125 



Curious Phenomenon in Capillarity. — S. A. Hill . . 125 

 Sense of Taste or Smell in Leeches. — Prof. A. G. 



Bourne 125 



Lisping. — A Ncn-Lisper 126 



Etiology of Scarlet Fever. By Dr. E. Klein, F.R.S. 126 

 The Secohmmeter. By Prof. W. E. Ayrton, F.F.S., 



and Prof. John Perry, F.R.S, {Illustrated) .... 129 



The Fosbil Fishes of Mount Lebanon 132 



Complimentary Dinner to Professor Tyndall . . . 133 



M. Boussingault 134 



Notes 135 



Our Astronomical Column : — 



Comet 1887 £ (Barnard, May 12) 138 



Minor Planet No. 266 138 



The Parallax of o Tauri 138 



Madras Meridian Observations 138 ^ 



Astronomical Phenomena for the Week 1887 



June 12-18 138] 



Geographical Notes 138 1 



The Annual Visitation of the Royal Observatory . 139J 



University and Educational Intelligence 142 f 



Societies and Academies 142 



Books, Pamphlets, and Serials Received 144 j 



