6oo 



NA TURE 



[April 19, 1906 



the results obtained can be most readily explained by 



ass my that certain bands correspond to the vibrations 



of positive ions. — The production of high vacua by means 

 oi liquid air: Georges Claude and Rene J. Levy. The 

 arrangement is based on the absorption of gases by char- 

 coal at the temperature of liquid air.— The acoustic proper- 

 tie- of certain hall- for speaking: M. Maragre. Experi- 

 ment- confirming the views put forward on the resonance 

 of halls by Wallace Sabine.— The variations of some 

 properties of quartz: H. Buisson. Two fine specimens of 

 quartz were compared, measurements being made of their 

 density, coefficient of expansion, double refraction, refrac- 

 tive iridsx. :nd rotatory powir. Th:r: wer; distinct JifLr 

 ences between the two specimens, all the deviation- being 

 in the same sense. It i- thus clear that quartz, even well 

 crystallised, cannot be considered as a perfectly pure sub- 

 ith absolutely defined properties, or even as a 

 homogeneous body.— The radio-activity of springs of drink- 

 ing water : I-'. Dienert. — Some pyrophosphoric compounds : 

 I cavalier. The preparation and properties of the pyro- 

 phosphorii esters oi ethyl, propyl, butyl, and amy! alcohols 

 ,,,. di ;cribed. ["hey all proved to have molecular weights 

 corresponding to the formula R,P„0-, determined by the 



cryoscopi thod Barium iodomercurates : A. Duboin. 



—The pure ferromolybdenums : ban. Vigouroux. In the 

 direel combination of iron and molybdenum with the iron 

 ,, excess, the definite compound Fe 2 Mo is formed, and no 

 othei compound containing less molybdenum appeal-, to be 

 capable of existence.— The influence of the ketonii and acid 

 grouping in the same molecule: L. J. Simon. — The con- 

 densation of the acetylenic amides with phenols. A general 

 method for the synthesis of ethylene-oxyphenol amides : 

 Ch. Moureu and J. Lazennec. — The genesis of an iron 

 mineral : I.. Cayeux. — A preliminary note on globoids and 

 certain granulations of seeds, resembling the metachromatic 

 corpuscles in some of their properties: J. Beauverie and 

 A. Guilliermond. The Khaya of Madagascar: H. 

 jumciie and II. Perrier de ia Bathie. Reasons are 

 shown for regarding this as a new species, Khaya 

 madagascariensis,— Study of the variations of nitrogen and 

 phosphoric acid in the juices oi a grass plant : G. Andre. 

 — The treatment of -eed with copper -alts : E. Breal. '1 he 

 superficial sterilisation of seeds by copper solutions nol 

 onl; prevents cryptogamic diseases, but also causes a good 

 utilisation of the reserves. — The heats of combustion and 

 the composition of the bone- of the skeleton of the guinea- 

 pig, considered a- a function of the age: J. Ti-ibot. — I he 

 nucleus of the red blood corpuscles in birds : M. Piettre 

 and A. Vila. — The Pleistocene glacier- in the valleys oi 

 Andorra and the neighbouring high Spanish valleys Marcel 

 Chevalier. — Contribution to the Tertiary flora of northern 

 Morocco: Ed. Bonnet. — Observation- on moving shadows 

 at sunset and sunrise : CI. Rozet. The phenomenon of 

 moving shadows has hitherto been observed only during 

 an eclip-e of the sun. The author points out the con- 

 ditions under which the -ante phenomenon can be seen at 

 sunset and sunrise. — Measurements of the variations of the 

 gravitation constant in the Simplon Tunnel: Marcel 

 Brillouin. -The results of atmospheric studies in the region 

 of ifie trade wind- : L. Rotch and I.. Teisserenc de Bort. 



Capi Town. 



South African Philosophical Society, February 28.— 

 Dr. J. C. Bealtie, president, in the chair. — Rock speci- 

 men- -bowing the occurrence of Glacial beds in the Griqua 

 Town series oi Hay: A. \Y. Rogers. Flattened md 

 striated stones, the peculiarities of which can at present 

 .ilk be attributed to glacial agencies, occur in a hard 

 ferruginous rock near the top of the Griqua Town series 

 in Hay. Thev are of various sizes, from an inch or two 

 up to 18 inches long. They consist of chert; a few grit 

 pebbles are found, but as yet no granites or other igneous 

 rock- are known from those beds; some hollows, now 

 partly filled with specular iron, may represent limestone 

 fragments. The boulders are scattered at wide intervals 

 through the matrix in most cases, though gravelly grits 

 al-o occur. — Under water in south-eastern Bechuanaland : 

 A. I.. Du Toit. The term south-eastern Bechuanaland i- 

 used as including the divisions of Mafeking and Vryburg 

 a- far westwards as Kuruman. — A -et of linear equations 

 connected with homofocal surfaces : Dr. Thos. Muir. 



DIARY OF SOCIETIES. 



MONDAY, April 23. 

 Society of Arts, at 8.— Ivory : Alfred Masked. 



Victoria Institute, at 4.30.— Review of Sir Henry H. Howorth s "Ice 

 or Water" : Prof. Edward Hull, F.R.S. 



WEDNESDAY, April 25. 

 Geological Society, at 8.— Tiilobites from Bolivia, collected by Dr. 

 I W Evans in 1001-1902: Philip Lake. — Graptolnes from Bolivia, 

 collected by Dr. J. W. Evans in 1901-1902 : Dr. E. M. R. Wood.— The 

 Phosphatic Chalks of Winterbourne and Boxford (Berkshire): H. J. 

 Osborne White and Llewellyn Treacher. 



THURSDAY, April 26. 

 at 5.— The Digestive Tract in Birds and Mammals : 



Seistan, Past and Present: Colonel A. H. 



al Engineers, at 8. — Long Flame Arc 



Royal Institu 



Dr. P. Chalmers Mitchell 



Society of Arts, at 4.3c 

 McMahon. 



Institution of Elect 

 Lamps: L.Andrews. 



Mathematical Society, at s ^o.— Perpetuant- and Contraperpetuanls 

 Prof. E. B. Elliott. -(1) A "Question in the Theory of Aggregates 

 (2) 1 he Canonical Forms of ihe Ternary Stxtic and Quaternary Quartic 

 Prof A. C. Dixon.— On ihe Question of the Existence of Transfinit 

 Numbers: P. E. B. lourdain.— Some Theorems connecled with Abel 

 Theorem on the Continuity of Power Series: (i. H. Hardy.— On a St 

 of Intervals about the Rational Numbers: A. R. Richardson. 



FRIDAY, April 27. 

 Royal Institution, at 9. — Ore Deposits and their Distribution i 



Depth : Prof. J. W. Gregory, F.R.S. 

 Institution ok Mechanical Engineers, at 8.— Petroleum Fuel 1 



Locomotives on the Tehuantepec National Railroad of Mexico : Lou 



'hvsical Society, at 5. 



leronauttcal Societv, at 8.— The Use 

 Antaictic Expedition: Captain Robe 

 Experiments of the Brotheis Wright: S 



CONTENTS. page 



The Glossopteris Flora. By A. C. Seward, F.R.S.. 577 



A Group of Text-Books of Physics 578 



Manufacture of Aluminium. By F. M. P 579 



Petrol Motor-Cars 580 



Our Book Shelf: — 



Heath :" Our Stellar Universe" 581 



Beadle : "Chapters on Paper-making" 5S1 



" Anales del Museo Nacional de Buenos Aires." — 



R. L 5 8 ' 



White: "The Natural History of Selborne" .... 581 

 Letters to the Editor: — 



The Existence of Absolute Motion. — Daniel 



Comstock 582 



The Magnetic Inertia of a Charged Conductor in a 



Field of Force. — Oliver Heaviside, F.R.S. . . 5S2 



Old Customs and Festivals.— W. Semple . . . 582 

 Chemistry in Rural Secondary Schools. — T. S. 



Dymond . 5*>3 



Diurnal Periodicity of Ionisation of Gases. — Alex. 



Wood 583 



New Spot on Jupiter. — W. F. Denning 584 



Oscillation of Flame Cones.— Prof. W. Galloway . 504 

 Interpretation of Meteorological Records. — A. 



Lander . 5^4 



Effect of Solar Eclipse on Fish.— A. Mosely, C.M.G. 5S4 

 Sea-sickness and Equilibiation of the Eyes.— Dr. 



Geoffrey Martin 584 



An Ethnological Survey of the Philippines. {Illus- 

 trated.) By Dr. A. C. Haddon, F.R.S 584 



The Oceanography of the Pacific. (Illustrated.) 586 

 Agricultural Research in India By Sir W. T. 



Thiselton-Dyer, K.C.M.G., F.R.S 5S7 



The Eruption of Vesuvius 5^8 



Notes 5S-9 



Our Astronomical Column : — 



The Continuous Spectrum of the Chromosphere . . 592 

 Objective- prism Determinations of Stellar Radial 



Velocities . 59 2 



The Observation of Long-period Variables 592 



Geology in Practice. (Illustrated.) By J. A. H. . . 593 

 Studies of Temperature and Pressure Observations. 



By Dr. William J. S. Lockyer 594 



The Mineral Wealth of Alaska 595 



University and Educational Intelligence 596 



Societies and Academies. (Illustrated.) 597 



Diary of Societies 600 



NO. I9O3, VOL. 73] 



