240 



NATURE 



[July 6, 1893 



and not the geographical equator, is really the dividing line 

 between the currents of the northern and southern hemispheres. 



Paris. 



Academy of Sciences, June 26. — M. Loewy in the chair. — 

 On the employment of Lagrange's equations in the theoiy of 

 impact and percussions, by M. Paul Appell. — Theoretical cal- 

 culation of the inferior contraction in weirs with thin walls and 

 sheets free below, when this contraction attains its greatest 

 values ; with experimental verifications, by M. J. Boussinesq. — 

 Formation of natural phosphates of aluminium and iron ; phe- 

 nomena of fossilisation, by M. Armand Gautier. Aluminium 

 phosphate was formed in the Minerva grotto by the action of 

 ammonium phosphate, resulting from the destruction of a bank 

 of guano, upon a subjacent layer of hydrargilite. This action 

 is easily reproduced experimentally. It is even possible to form 

 a small quantity of aluminium phosphate by the prolonged 

 action of ammonium phosphate upon kaolin. Iron phosphates 

 are produced by the action of ammonium phosphate upon 

 spathic iron ore. This is probably the usual origin of 

 vivianite. It is shown that the simultaneous formation of am- 

 monia, sulphuretted hydrogen, and other products of slow bac- 

 terian fernientalion, with the action of the air dissolved in 

 water, gives rise, in strata at the same time calcareous and fer- 

 ruginous, to the simultaneous production of lime phosphates 

 and of pyrites. — Note by M. Daubiee accompanying the pre- 

 sentation, in the name of its authors, of the geological map of 

 European Russia. — Obseivalions of theplanet Charlois (1S93Z) 

 made with the 14-inch equatorial of the Bordeaux Observa- 

 tory by M. L. Picart. — On the maximum modulus which 

 a determinant can attain, by M. lladamard. — Experimental 

 determination of the constant of universal attraction, and of the 

 mass and density of the earth, by M. Alphonse Berget. — On 

 the third principle of energetics, by M. H. Le Chatelier. The 

 laws of the conservation of mass, of momentum, of quantity 

 of electricity, of the centre of gravity, &c. , can be embodied in 

 a single law as follows : The individual "energy capacities " of 

 an isolated system are constant, except that of heat (entropy) 

 which increases in irreversible transformations. This "energy 

 capacity," so termed by Ostwald, is made up of several factors 

 of the type of those enumerated above.— On the employment of 

 mercury in potential equalisers by flow, by M. G. Goure de 

 Villemontee. — Research on the dielectric constants of some 

 biaxial crystals, by M. Ch. Borel. The principal constants of 

 five rhombic and ten clinorhombic substances were determined 

 by finding their axes of polarisation and measuring their periods 

 of oscillation in a uniform electric field, and also measuiing the 

 attraction along each axis of polarisation. The crystals were 

 cut in the shape of spheres. The attraction method was like 

 that used by Bollzmann, except that his bifilar balance was 

 replaced by a unifilar quartz fibre balance. Most of the sub- 

 stances examined were double sulphates. A redetermination 

 of the constants for rhombic sulphur showed a closer agreement 

 with Maxwell's law than Boltzmann's results. — On a new method 

 of directly transforming alternating into direct currents, by M. 

 Charles Pollak. — On the combinations of oxalic acid 

 with titanic and stannic acids, by M. E. Pechard. — 

 Researches on the chlorosulphides of arsenic and anti- 

 mony, by M. L. Ouvrard. — Action of carbonic oxide upon 

 sodammonium and potassammonium, by M. A. Joannis. — On 

 the combinations of boron bromide with the bromides of phos- 

 phorus, by M. Tarible.— On the action of zinc and magnesium 

 on metallic solutions and on the estimation of potash, by MM. 

 A. Villiers and Fr. Borg. — Observations on a marine miocene 

 randannite of theLimagne d'Auvergne, by M. Paul Gautier. — 

 The duration of excitability of the nerves and muscles after 

 death is much greater than is generally believed, by M. A. 

 d'Arsonval. This may be shown by means of the myophone, a 

 kind of microphone arranged so as to indicate small muscular 

 contractions. The instrument gives indications of muscular 

 excitability in a rabbit even ten hours after death. — Remarks on 

 M. d'Arsonval's paper, by M. Brown-S^quard. The fact that a 

 muscle under the influence of complete cadaveric rigidity, re- 

 maining perfectly inert under the influence of the strongest im- 

 pulses provoking contraction, is capable of rhythmic motor actions 

 when its nerve is excited, is one of the most interesting dis- 

 coveries in the physiology of nerves and muscles. — Sketch of the 

 principal anatomopathological types of adult chronic gastritis, 

 by M. Georges Hayem. — Observations on ice, made during the 

 cruise of La Manche, by M. G. Pouchet. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



BcoKS.— Elementi of Psychology: Prof. J. M. Baldwin (Macmillan). — 

 Everybody's Guide to Music: J. Booth (Saxon). — A Handbook oa the 

 Steam-Enginc : H. Haeder, translated by H. H. P. Powles (C. Lockwood), 

 — Murray's Handbook — Switzerland, Savoy, Piedmont, i8lli edition (Mur- 

 ray). — University Correspondence College Calendar, 1S92-93 (London). — 

 Worked Examples in Co-ordinate Geometry (Clive).— A Biographical Index 

 of British and Irish Botanists: J. Brilten and G. S. Bimlger (West, New- 

 man).— Foundations of the Atomic Theory (Alembic Club Reprints, No. a) : 

 Dalton, Wollaston. and Thomson (Edinburgh, Clay).— Im Reiche des 

 Lichtes, Sonnen, Zodiakallichle, Kometen : H- Gruson (.^sher).- Hourly 

 Meteorological Observations made at the Madras Observatory, January, 

 1856, to February, 1861 (Madras). 



Pamphlets.— Sir J. B. Lawes and the Rothamsted Experiments; C. M. 

 Aikman (Glasgow).— U.S. Department of Agriculture : Reports of Observa- 

 tions and Experiments in the Practical Work of the Division (Washington).— 

 Traces of Glacial Man in Ohio : W. H. Holmes (Chicag..).— Are there 

 Traces of Man in the Trent on Gravels : W. H. Holmes (Chicago).— Distri- 

 bution of Stone Implements in the Tide- Water Country: W. H. Holmes 

 (Chicago).— Report and Proceedings of the Ealing Microscopical and 

 Natural History Society for 1892 (Ealing). — Yorkshire Carboniferous Flora : 

 R. Kidston (Leeds). 



Serials.— Proceedings of the Royal Society of Victoria, Vol. v. new 

 series (Williams and Norgate) —Journal of the Royal Microscopical Society, 

 June (Williams and Norgate), — Journal of the Asiatic Society of Bengal, 

 Vol. Ixi. Part 2, No. 3. 1892 (Calcutta).— Journal of the Royal Agricultural 

 Society of England, third series, Vol. 4, Part 2, No. 14 (Murray).— The 

 Botanical Gazette, June (Bloomington, Ind.) — Nyt Magazin for Natur- 

 videnskaberne, 33te Binds, 4de og, 5te Hefte (Christiania).— L'Astronomie, 

 July (Paris).— Himmel und Erde, July (Berlin).— Journal of Bouny, July 

 (West, Newman). 



CONTENTS. PAGE 



The Great Barrier Reef of Australia. By Prof. 



Alfred C. Haddon 217 



Bacteriology for the Public 219 



Thermodynamics. By J. W 220 



Our Book Shelf:— 



Holman : "Discussion of the Precision of Measure- 

 ments" 221 



Guerin: "Trailed'AnalyseChimiqueetde Recherches 



Toxicologiques " 221 



Letters to the Editor : — 



Identification.— Francis Galton, F.R.S 222 



The Publication of Physical Paper.«.— A. B. Basset, 



F.R.S. . 222 



A Simple Rule for finding the Day of the Week corre- 

 sponding to any given Day of the Month and Year. 



— Cr. C. Braun ... 222 



The Fundamental Axioms of Dynamics.— Prof. J. G. 



MacGregor 223 



Artistic Rows of Elm?.— Rev. Alex. Freeman . . 223 



Soaring of Hawk.— F. C. Constable 223 



Carrier Pigeons.— F. W. Headley 223 



A Method of obtaining Glochidia.— G. P. Darnell- 

 Smith . 223 



A New Statue of Arago. {Illustrated.) 223 



Modern Mycology. By Prof. H. Marshall Ward, 



F.R.S ^H 



Daubree on the Geological Work of High-Pressure 



Gas 226 



Notes . 228 



Our Astronomical Column : — 



Comet Finlay (1886 VII.) 233 



A Bright Comet ? 233 



Stars with Remarkable Spectra 233 



J he Period of Rotation of Venus »33 



The Newall Telescope 233 



Johnston's Notes on .\stronomy 233 



The Hodgkins Fund Prizes 233 



Geographical Notes 233 



Museums Association. I. By Sir William H. 



Flower, K.C.B,, F.R.S 234 



Marine Biological Association 236 



The Conditions Determinative of Chemical Change. 



By Prof. Henry E. Armstrong, F.R.S 237 



The Succe: sion of Teeth in Mammals 238 



University and Educational Intelligence 238 



Scientific Serial 239 



Societies and Academies 239 



Books, Pamphlets, and Serials Received 240 



NO. 1236, VOL. 48] 



