336 



NA TURE 



{Feb. 2, 1888 



limit, these distances form a geometric progression modified by a 

 periodic irregularity. In a future communication the connection 

 will be pointed out between this law and the theoretic views 

 advanced by the author on the formation of the planetary 

 system. — Summary of the solar observations made at Rome 

 during the last quarter of the year 1887, by M. P. Tacchini. 

 The diminution of spots already noted in September was con- 

 tinued during the two ensuing months, so that the mean was 

 even less than in the previous quarter. The protuberances also 

 were less frequent. — On the phases of Jupiter, by Dom E. 

 Siffert. Most of these observations, which were taken at the 

 Observatory of Grignon, are tabulated for the period from 

 March to December, 1885. — On the application of the Cre- 

 monian quadratic sulistitutions to the integration of the 

 differential equation of the first order, by M. Leon Autonne. In 

 this paper the author develops, for the integration of the 

 differential equation of the first order, the method based on the 

 employment of the Cremonian quadratic substitutions, and 

 applies this method to some special cases of a simple and com- 

 prehensive character. — Electric solution of algebraic equations, 

 by M. Felix Lucas. It is shown how, by means of electricity, 

 the solution of equations of any degree /, whose real or 

 imaginary coefficients are given numerically, may be reduced to 

 that of equations of degrees lower than /. — Action of vanadic 

 acid on the alkaline fluorides, by M. A. Ditte. The present 

 paper deals with the fluorides of sodium and ammonium, whose 

 composition is shown to be analogous to that of the fluoride of 

 potassium. — Action of hydrochloric acid on cupric chloride, by 

 M. Engel. The results are tabulated of a series of experiments 

 with the hydrochlorate of cupric chloride. In this substance the 

 chloride of copper appears to be in the anhydrous state, all the 

 water being ultimately combined with the hydrochloric acid. — 

 On the alcoholic fermentation of galactose, by M. Em. Bourque- 

 lot. From these experiments, undertaken to determine the 

 true character of the action of the yeast of beer on galactose, the 

 author concludes that pure galactose does not ferment in the 

 presence of the yeast at 15° to 16° C, but that it undergoes 

 alcoholic fermentation when glucose, laevulose, or maltose are 

 added. — On two new genera of Epicarides, by MM. A. Giardand 

 J. Bonnier. The specimens here described live in the fresh 

 waters of the Dutch East Indies, and are regarded as the types 

 of two new genera, Probopyrus and Palegyge, whence are 

 respectively derived the genera Bopyrus and Gyge. They are 

 here named Probopyrus atcendens, Semper, and Palegyge 

 borrei, G. and B. 



Berlin. 



Physiological Society, January 13. — Prof, du Bois Rey- 

 mpnd, President, in the chair. — Prof. Fritsch described the 

 detent-joint of a Sheat-fish (Siluridee). In this fish, as found in 

 the Nile, the adjusting and fixing of the dorsal and pectoral fins 

 is provided for by the various shape and arrangement of the 

 surfaces of the joints, which take the form of hooks and de- 

 tents. The speaker explained the above arrangements by means 

 of drawings and preparations, by means of which it w^as easily 

 seen that when once the dorsal spine is fixed it will withstand 

 a very considerable force. These spines constitute a protective 

 mechanism against other predatory fishes, and accounts for the 

 numerical development of these fishes in the Nile. The speaker 

 stated his inability to accept Sorensen's view that the detent- 

 joints of these fishes are organs for the production of sound. — Dr. 

 Joseph had studied the minute structure of the axis-cylinder in 

 the nerves of the electric organ of Torpedo niarmorata treating 

 them with osmic acid and various staining reagents. By making 

 a careful series of transverse sections he has become convinced 

 that not only the medullary sheath, but also the axis cylinder, 

 possesses a fan-like structure, and that the longitudinal fibrils 

 run in the meshes of the radiating fibres, and are the true con- 

 ducting tissue of the nerve. The diameter of the axis is six 

 or seven times as great as that of the sheath. — Dr. Weyl had sub- 

 jected silk to a thoroughly chemical examination, and obtained 

 values for its percentage composition, after purification by treatment 

 with caustic soda, which corresponded with those given twenty- 

 five years ago by Cramer ; according to these, silk may be taken 

 as belonging to the proteid class of bodies. Raw silk, and to a 

 greater degree that which has been purified by soda, is soluble in 

 fuming hydrochloric acid ; if this solution is poured into alcohol, 

 a white cloudiness is produced, which speedily increases in in- 

 tensity, and on cooling gives rise to a solid white gelatinous 

 mass. The "percentage composition of this new substance ob- 

 tained from silk, and called by the speaker seroin, is, as regards 



its carbon and hydrogen, the same as that of silk, but it contains 

 less nitrogen. It possessed in ail cases the same composition, so 

 that it is undoubtedly a distinctly characterized chemical sub- 

 stance, and is neither pure silk nor some closely related proteid 

 formed by a splitting-off of ammonia. When treated with dilute 

 acids, seroin yields the same products of decomposition as does 

 fibroin — namely, large quantities of leucin and tyrosin, by which 

 it is characterized as being a proteid. Dr. Weyl hoped shoiily 

 to resume this investigation in the direction of a general con- 

 sideration of the proteid group. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Voltaic Electricity : T. P. Treglohan (Longmans). — Practical Physics for 

 Schools and ihe Junior Students of Colleges, vol. i. Electricity and Magnet- 

 ism : Stewart and Gee (Macmillan). — Behind the Tides : C. B. Radcliffe 

 (Macmillan). — Pflanzen-'Ieratologie : M. T. Masters ; German by U. 

 Dammer (Leipzig). — Practical Amateur Photography; C. C. Vevers, 



CONTENTS. PAGE 



The Composition of Water. By Prof. T. E. Thorpe, 



F.R.S y^ 



Physical Geography of the Sea. — Hon. Ralph Aber- 



cromby 315 



Bulletin of the United States Fish Commission . . 316 

 Our Book Shelf :— 



Kick: " Flour Manufacture " 316 



Remsen : " Elements of Chemistry " 317 



Warren: " A Primary Geometry " 317 



Letters to the Editor : — 



The Duke of Argyll's Charges against Men of Science. 



—Prof. John W.Judd, F.R.S 317 



The Total Eclipse of the Moon of 1888 January 28, 

 observed at Biir Castle Observatory, Parsonstown. 



Otto Boedicker 318 



" Elementary Chemistry " and "Practical Chemistr}'." 



— M. M. Pattison Muir 318 



" Physical Science and the Woolwich Examinations." 



— W. A 319 



' ' The Art of Computation for the Purposes of Science." 



— E. Erskine Scott ; George King 319 



Note on a Problem in Maxima and Minima. ( With 



Diagram.) — R. Chartres 320 



Note on the Dimensions and Meaning of J, usually 

 called the Mechanical Equivalent of Heat. — Alfred 



Lodge 320 



The Temporary Thermo-Current in Iron. — Fred. T. 



Trouton 321 



Causes influencing the Bathymetrical Range of Deep- 



Sea Fishes. — A, R. Hunt 321 



Wind Force at Sea. — W. G. Black 321 



Untimely Insect Development. ^ohn Morison . . 321 



Weasels killing Frogs. — M. S. Pembrey 321 



"British and Irish Salmonidae." — Your Reviewer . 321 

 Modern Views of Electricity. Part III. VI. {Illus- 

 trated). By Dr. Oliver J. Lodge, F.R.S 322 



Language-Reason. By Prof. F. Max Miiller . . . 323 



Ferdinand Vandeveer Hayden 325 



Notes 327 



Our Astronomical Column : — 



American Observatories 330 



Astronomical Phenomena for the Week 1888 



February 5-1 1 330 



Geographical Notes 330 



Our Electrical Column 331 



The Proposed Teaching University for London . . 331 

 The Total Eclipse of the Moon, January 28 .... 333 



Societies and Academies 333 



Books, Pamphlets, and Serials Received . . , . , 33$ 



