12 



NATURE 



[January 25, 1900 



Swyngedauw of the effect of the X-rays upon the discharge of 

 bodies just below their ordinary sparking potential, it ha^ proved 

 to be possible to obtain comparative measurements of the 

 velocity, which would appear to be of the same order as ultra- 

 violet light. — On the nature of white light and the X-rays, by 

 M. E. Carvallo. — The numerical laws of chemical equili- 

 brium, by M. O. Boudouard. The formula of Le Chatelier 

 is applied to the reaction CO3 -f C ^ 2CO2, and the com- 

 position of the gas mixture calculated for temperatures be- 

 tween 450" C. and 1050" C— On the electrolysis of potas- 

 sium chloride, by M. A. Brochet. The yield of chlorate is 

 considerably increased by the presence of a little potassium 

 bichromate in the solution. Curves are given showing the 

 amounts of chlorine present as hypochlorite, chloride, and 

 chlorate after a varying number of ampere hours. — On a new 

 crystallised molybdenum sulphide, by M. Marcel Guichard. 

 By heating molybdenum bisulphide in the electric furnace a 

 lower sulphide, MogSj, is produced, which can be obtained as 

 long steel-grey needles from the melted mass by treatment with 

 aqua regia. Heated to a red heat in sulphur vapour the bisul- 

 phide is reformed ; at higher temperatures it is dissociated into 

 sulphur and molybdenum. — The action of magnesium upon 

 saline solutions, by M. Henri Mouraour. — Automatism of the 

 nerve cells, by M. Pompilian. Curves are given for the auto- 

 matic movements observed in Dytiscus Marginalis. The author 

 concludes that nerve cells are constantly disengaging nervous 

 energy, without any excitement being required, and hence that 

 nervous activity is really automatic, although varying in in- 

 tensity with time. The higher nervous centres under normal 

 conditions exert a controlling influence over the lower 

 centres, the activity of the latter being clearly shown 

 when the former are removed. Hence it would appear in 

 pathology that the tremors may be explained either by a 

 diminution of the controlling power exercised by the higher 

 cerebral centres upon the lower medullary centres, or by an 

 increase of activity of the latter. — On a category of crystalline 

 groups escaping optical investigations, by M. Fred. Wallerant. 

 In general, in a crystalline grouping, the different crystals can 

 be easily distinguished, their ellipsoids of optical activity having 

 different orientations. If, however, the orientation of the 

 crystals are symmetrical with respect to the elements of sym- 

 metry of this ellipsoid, it will be impossible to distinguish them 

 by polarised light. Cumenglite and chiastolite are considered 

 as ^examples. — On the denudatioa of the central plateau of 

 Haye, or Foret de Haye, by M. Bleicher.— On the presence of 

 the Upper Eocene in Tunis, by M. Flick. 



DIARY OF SOCIETIES. 



THURSDAY, January 25. 



Royal Society, at 4.30.— Mathematical Contributions to the Theory of 

 Evolution— On the Law of Reversion: Prof. K. Pearson, F.R.S. — 

 (i) On the Mechanism of Gelation in Reversible Colloidal Systems: 

 (2) .\ Preliminary Investigation of the Conditions which determine the 

 Stability of Irreversible Hydrosols : W. B. Hardy.— On the Effects of 

 Strain on the Thermo-electric Qualities of Metals, Part II. : Dr. M' 

 Maclean. — On the Periodicity in the Electric Touch of Chemical 

 Elements. Preliminary Notice : Prof. J. C. Bose. 



Royal Institution, at 3.— The Senses of Primitive Man: Dr. W. H. 

 R. Rivers. 



Institution OP Electrical Engineers, at 8.— Adjourned Discussion 



on the Report of the Institution's Visit to Switzerland. And if time 



permit : An Electrolytic Centrifugal Process for the Production of Copper 

 Tubes : Sherard Cowper-Coles. 



.Fif/i?^K, January 26. 



Royal Institution, at p.— Motive Power, High Speed Navigation, 

 Steam Turbines : Hon.C. A. Parsons, F.R.S. 



Physical Society, at 5.— Some Developments in the Use of Price's 

 Guard Wire in Insulation Tests : Prof. Ayrlon and Mr. Mather — Re- 

 flection and Transmission of Electric Waves along Wiras : Dr. E. Barton 

 and Mr. L. Lownds. — The Frequency of the Transverse Vibrations of a 

 Stretched India-rubber Cord : T. J. Barker. 



Institution OF Mechanical Engineers, at 8. — Water Meters of the 

 Present Day, with special reference to Small Flows and Waste in 

 Dribbles : William Schonheyder. 



Institution of Civil Engineers, at 8. — The Simplon Tunnel : C. B. 

 Fox. 



SATURDAY, January 27. 



Mathematical Association (University College, Gower Street, W.C.), 

 at 2. — Dynamical Applications of the Theory of Correspondence : Sir 

 Robert S. Ball.— Triangles Triply in Perspective: J. A. Third.— The 

 Teaching of Indices and Surds : Prof. R. W. Genese. — Illustrations of 



NO. 1578, VOL. 61] 



Porismatic Equations: T. J. Bromwich — A Note on the Focoids : R. F. 

 Davis. 

 Essex Field Club, at 3. — Visit to Museum of College of Surgeons. Con- 

 ductor : Prof. C. Stewart, F.R.S. 



MONDAY, January 29. 



Society of Arts, at 8. — The Nature and Yield of Metalliferous De- 

 posits : Bennett H. Brough. 



Institute of Actuaries, at 5.30. — Increasing Reversionary Charges: 

 W. B. Paterson 



TUESDAY, January 30. 



Royal Institution, at^. — Structure and Classification of Fishes ; Prof. 

 E. Ray Lankester, F.R.S. 



Anthropological Institute, at 8.30. — Anniversary Meeting. 



Institution of Civil Engineers, at 8. — Steamers for Winter Naviga- 

 tion and Ice-breakine : Robert Runeberg. 



WEDNESDAY, January 31. 

 Society of Arts, at 8.— The Undeveloped Resources of the Bolivian 

 Andes : Sir W. Martin Conway. 



THURSDAY, February i. 



Royal Society, at 4.30. — Probable Papers: A Case of Monochromatic 

 Vision : Sir W. de W. Abney, F R.S.— Thermal Radi^'ion in Absolute 

 Measure: Dr. Bottomley, F.R.S., and Dr. Be.\ttie. ^Electrical Con- 

 ductivity in Gases traversed.by Kathode Rays : Dr. McLennan. 



Royal Institution, at 3. — Ihe Senses ot Primitive Mau : Dr. W. H. R. 

 Rivers. 



Linnean Society, at 8. — On Botanic Nomenclature: C. B. Clarke, 

 F.R.S.— On the Zoological Results of an Expedition to Moiint Roraima, 

 in British Guiana, undertaken by Messrs. F. V. McConnell and J. J. 

 Quelch: Prof. E. Ray Lankester, F.R.S. 



Chemical Society, at 8. — The Chlorine Derivatives of Pyridine. 

 Part V. Synthesis of aa'-Dichlorpyridine. Constitution of Citrazinic 

 Acid : W. J. Sell and F. W. Dootson.— The Formation of Heterocylic 

 Compounds: S. Ruhemaim and H. E. Stapleton. — The Space Configura- 

 tion of Quadrivalent Sulphur Derivatives : Methyl Ethyl "Thetine Dextro- 

 camphorsulphonate, and Dextrobromocamphorsulphonate : W. J. Pope 

 and S. J. Peachey. — Nitrocamphane : M. O. Forster. 



Rontgen Society, at 8. — Rontgen Rays in Di.'-eases of the Chest : Dr. 

 Hugh Walsham. — Mr. A. Hastings Stewart will show a small Egyptian 

 Mummy and Skiagrams of the same. 



FRIDAY, February 2. 



Royal Institution, at g. — Wireless Telegraphy : G. Marconi. 



CONTENTS. 



PAGE 



Prof. 



293 



294 

 294 

 294 

 294 

 295 



295 



The Old and the New Kinetic Theory. By 



G. H. Bryan, F.R.S 289 



The Zoology of the Indian Seas 291 



Antiquities of Central America. By A. H. Keane . 292 

 Our Book Shelf:— 



Camerarius : "Das Geschlecht der Pflanzen." — 



A. W. B . . 



"Journals and Papers of Chauncy Maples, D.D., 



F.R.G.S., late Bishop of Likoma, Lake Nyasa."— 



J. F. H 



Van't Hoff : " Le9ons deChimie Physique." — J. W. 



Aloi : "Gli Agrumi " 



Ball : " Star-Land " 



Christison : " Brain in Relation to Mind " 



Letters to the Editor:— 



Is New Zealand a Zoological Region ?— Prof. Alfred 



Newton, F.R.S 



Compensation in Weather. {With Diagram.)~M^-x.. 



B. MacDowall 295 



The Methods of Inorganic Evolution. II. By Sir 



Norman Lockyer, K.C.B., F.R.S 296 



The London University Election 299 



American Higher Technical Education. By Prof, 



F. W. Burstall 299 



Armour Plates. By R. A. Hadfield 301 



Notes 301 



Our Astronomical Column: — 



Density of Close Double Stars 306 



A New Photographic Photometer 306 



A Brilliant Meteor in Sunshine 306 



Some Recently Discovered Silurian Fish Remains. 



A Link in the Chain of Organic Evolution. 



{Illustrated.) By G. B. H 307 



University and Educational Intelligence 309 



Scientific Serials 310 



Societies and Academies 311 



Diary of Societies 3 



