484 



NA TURE 



[September 14, 1893 



tronoiners many suggestions as to work desirable to be done, 

 he, nevertheless, wishes to fulfil the main work of the observa- 

 tory, which consists in observation? of lunar occultations of 

 stars, southern comets, and the meteorological observation". 

 That Mr. Tebbatt is thinking about seeking so:ne relaxati 'n, is 

 only natural when one considers how his powers mu«t have 

 been taxed during the last few years ; and we sincerely hope that 

 after a good holiday and rest he may come back to his work 

 again a new man, and continue the work he has so ably 

 begun. 



Universal Time in Australia. — With three meridians 

 differing by one hour from one another passing through the 

 continent of Australia, the question has been raised as to 

 whether only cential lime should be used, or all three times. 

 (The Observatory for September). Adopting the latter, it will be 

 nece-sary, of course, for frequent cliani^es of time to be made ; 

 but with the former, although places on the extreme east and 

 west would have their time about \\ hours away from local 

 time, greater convenience for railways, telegrapii work, &c., 

 will be gained. Sir Charles Todd, who supports this latter 

 view, and who is backed by the Hon. f. G.Ward (New Zealand), 

 the Hon. J. Kidd (N.S.W.), and the Hon. A. Wynne (Victoria), 

 came to the following conclusion at the Postal and Telegraph 

 Conference held in Brisbane this year, when the subject of the 

 Hour Zone Time was being considered : — " That it is 

 desirable in the public interests that the Hour Zone system 

 should be adopted in a modified form, so that there should be 

 one time throughout Australia, viz. that of the l3Sth meridian, 

 or nine hours east of Greenwich." 



SOCIETIES AND ACADEMIES. 



Paris. 



Academy of Sciences, September 4 — M. Loewy in the 

 chair. — Report upon a memoir by M. Defforges, entitled, on 

 the dislribuiion of the intensity of gravity at the surface of the 

 globe, by MM. Fizt-au, Daubree, Cornu, Bissot, Tisserand. 

 This memoir, submitted to the judgment of the Academy by 

 the Minister of War, summarises the theoretical and expcii- 

 mental researches made during eight years in the geographical 

 service of the army, with the objec: of determining the absolute 

 intensity of gravitation for a small number of primary stations, 

 and the relative intensity for a large number of secondary 

 stations with simplified apparatus. The latter were determined 

 by mean? of th*" " reveisible invertible pendulum " invented by 

 M. Defforges, which exceeds all used previously in lightness 

 and convenience, and easily gives an approximation to within 

 I part in 100,000. The anomalies extending along a line from 

 Spitzh'.rgen through the Shetlands, Sc itland, England, France, 

 and Algiers considerably exceed any possible experimental 

 errors, and the excess of gravitation on the islands and defect 

 on the continents is well established. The report, which was 

 adopted by the Academy, advises the Government to ^upply M. 

 Defforges with the means to extend his work to the islands of 

 the southern hemisphere and e-pecially the Pacific. — The hy- 

 pothesis of sub-continental bells, by M. Rateau. The 

 phenomena of the earth's crust are well explained and connected 

 by assuming that the crust underneath the continents does not 

 touch the fluid globe, but is separated from it by a space filled 

 with gaseous matter under pressure. The continents would thus 

 form a sort of bells, very much flattened, and supported by gas, 

 whereas the ocean beds would lie direct upon the igneous globe. 

 The continental projections tend generally to rise, blown up as 

 it were by the accumulating gas below, whilst the sea beds 

 sink. But the gases, imprisoned under high pressure, escape 

 gradually through the fissures of the crust, when the 

 production of new quantities 

 come insuflicient, the pressure 

 decrease, and these will be 

 crust underneath, giving rise 

 crateriform configurations. This is the state in which we see 

 the moon at the present time. If the earth's crust is assumed 

 to be 30 km. thick, the pressure of the gases should be 650 

 atmospheres and their temperature 900°. The gases would be 

 of a density nearly equal to that of water, and superposed iu 

 the order : hydrogen, methane, nitrogen, ethane, oxygen, car- 

 bonic anhydride. Hydrochloric acid and siliciuretted hydrogen 



from the nucleus will be- 

 under the continents will 

 projected upon the new 



to more or less extended 



would also probably be stable under these conditions. The 

 presence of gas underneath the continents, elevated as they are 

 above the sea and of greater density than water, is necessitatei! 

 by conditions of hydro.static equilibrium. It is easily seen wh) 

 volcanoes in the interior of continents never give off larva, but 

 only gases ; al<o why lines of coast volcanoes have succes' 

 sively receded inland where the sea encroached. — On the elim- 

 ination of foreign bodies in the Acephala and especially in Pho'.as, 

 by M. Henri Coupin. If the mantle and the ventral siphon 

 of •> Pholas are cut along their entire !e igth, and a collection ol 

 foreign particles are thrown upon the tentacles, the particles 

 falling upon the dorsal tentacles are carried away with great 

 rapidiiy, not towards the mouth, but upon that part of the 

 mantle which lies between the anterior luminous organ and the 

 palp. Thence they pass quickly towards the siphon region, and 

 are stuck together by mucus and rolled up into balls, which are 

 then extruded at the siphon. It is thus that the animal gets rid 

 of the particles of rock disintegrated during its boring opera- 

 tions, and protects its delicate internal canals. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Bocks. — Index to the Publicalijns of the Anthropolosical Ins-itute (1843 

 to 1891): G. W. Bloxam (Anthr pi>!ogicaI Institute)- — The Amphioxiis and 

 its Develotiment : Dr. B. Hatsc'iek, translated and edited by J. Tuckey 

 (Sonnenschein) — The Pharmacol cela of the United States of .\merica. 7th 

 Decennial Revision. 1890 (Philadelphia) — London Inter. Science and Pre- 

 lim. Sci Dirtclory, No. iv. July 1893 (London). — -Accidents de ChaudiC;res : 

 F. Sinigagla (Paris, Gauthier-Villars) — The irie des Jeux de Hazard ; H. 

 Laurent (Paris, Gauthier-Vtllars) — Smithsonian Institution. 'Report of 

 National Museum for Year ending June 30. 1891 (Washingtr^n) — .\n Ele- 

 mentary Text-book of Biology : J R. A Davis._2nd edition, 2 part* (Griffin) 

 — Pubhcazlone della Sp^cola Vaticana, fasc. iii. (Rome). — Bulletin of the 

 U.S. Fish (Jotnmission, Vol. x. for 1890 (Washington) — Index Kewensis: 

 Sir J. D. Hooker and B. D. Jackson. Fart i (Oxf rd, Clarendon Press). — 

 A Contrtbtttion to the Geology and Natttral History of Nottinghamshire; 

 edited by J. W. Carr (Nottingham, Bell) — lllusira'cd Hand-book of th« 

 Cape and South Africa : edited by J. Noble (Stanford) — Terra : A. A. 

 Anderson, 2nd edition (Reeves and Turner). 



Pamphlbts. — Abstract of Returns f irnished to the Department of Science 

 and Art (Kyre and Spottiswoode). — Report of Mr. Tebbutt*s Observatory^ 

 the Peninsula. Windsor, N.S W. 1892 : J. Tebbutt (Sydney). 



Serials.— Journal of the .'Anthropological Institute, August (K. Pnttll.— 

 Natural Science, September (Maciiillan) — Geological M.-igazine. Sci i-.m- 

 ber(K. Paul). —American Journal of Mathematics, V..I. xv. No. 3 (I'alti- 

 more). — Journal of the Asiatic Society of Bengal, Vol. 62. Part 2, No. i 

 (Calcutta).— Journal of the Chemical Society, September (Gtirney aid Jack- 

 son) — Proceedings of the American Philosophical Society, Vol. 31, No. 141 

 (Philadelphia) —Proceedings of the Rochester Academy of Science, VoLdh 

 Brochure 2 (Rochester, New Vork). -Geological and Natural Hbtoiy 

 Survey of Minnesota, Bulletin No. 8 (Minneap->lis). — Medical MagaziM 

 September (Southwood) —Proceedings o' the Royal Society of Ed nbur^ 

 Sessl 'n :?.a 91. Vol. ;.::. pp i '.'» c6- — Jo-'-'Pal of the College of ScienCSt 

 Imperial University, japan, Voi. 6, I'art 2 (Tokyo)- 



CONTENTS. PAOB 



The Mechanics of Fluids. By Prof. A. G. Green- 

 hill, F.R.S 4Sr 



Letters to the Editor :— 



Palaeozoic Glaciation in the Southern Hemisphere. — 



E. J. Dunn 45* 



Astronomical Photography. — Dr. A. A. Common, 



F.R.S 459' 



The Greatest Rainfall in Twenty-four Hours. — ^J. S. 



Gamble AS9 



Wasps.— J Lloyd Bozward -459 



The American Association. By Dr. William H. Hale 460 

 British Association. By Prof. Frank Clowes ... 4*3 

 Inaugural Address by J. S. Burdon-Sanderson, 

 M.A., M.D., LL.D., D.C.L., F.R.S., 

 F.R.S. E., Ptofessor of Physiology in the Uni- 

 versity of Oxford, Pre>ident 4*4 



Section A — Mathematics and Physics. — Opening 

 Address by R. T. Glazebrook, M.A., F.R.S., 



President of the Section 473 



Section B— Chemistry.— Opening Address by Prof. 

 Emerson Reynolds, M.D., Sc.D., F.R.S., 



President of the Section 477 



Notes . . 48' 



Our Astronomical Column : — 



Mr. ''^ebbi'tt's Observatory 4|3 



Univi..;:.. iir.-.e i.T Aus:;-r.i:a 4»4 



Societies and Academies 4°4 



books, Pamphlets, and Serials Received 484 



NO. 1246, VOL. 48] 



