[28 



NATURE 



I March 3], 1892 



combines with nitrogen directly only at a very high temperature ; 

 it readily reacts with a large number of salts. Its action on 

 metallic oxides, easily reduced by carbon, is very violent. (See 

 p. 522.)— On the preparation of boron iodide, by M. H. 

 Moissan. — On the origin of colouring matters in the vine ; the 

 ampelochroic acids and the autumnal coloration of vegetation, 

 by M. Arm. Gautier. — Experiments on vascular reflex action, 

 by M. L. Ranvier.— Contribu'ion to the history of morbid 

 associations : coexistence of stercorary retention with general 

 <liseases and injuries of the great viscerae, the kidneys in par- 

 ticular, by M., Verneuil, — Surface and population: European 

 States, by M. Emile Levasseur. The following values have been 

 taken from the tables given : — 



Surface, in 

 thousands uf 



Population, Density, or 



in millions ot number of 



States. °"?,'!"°'"' inhabitants inhabitants 



\,\\^^l*t. at the end of per square 



kilometres. ^^^ kilometre. 



West Europe ... 9i6"32 ... Sj'ii ... 95*0 



Central ,, ... I207"56 ... 93'6o9 ... 77-0 



South ,, ... i45o'565 ... 71-826 ... 50-0 



East ,, ... 5477"o ... 980 ... iS'o 



North ,, ... 9830 ... 9*1 ... 9-0 



Total 



10,034-445 



359 '645 



35- 



The methods of arriving at these numbers and other infor- 

 mation relating to them are fully explained. — Report on a 

 memoir, presented by M. Blondlot, on the propagation of 

 Hertz vibrations.^— Observations of comet a 1892 (Swift), made 

 at the Paris Observatory with the West Tower equatorial, by M. 

 G. Bigourdan. — Observations of comet c 1892, made at the Paris 

 Observatory with the same instrument, by the same author, — 

 Observations of Swift's comet (1892 March 6), made with the 

 great equatorial of Bordeaux Observatory, by M. G. Rayet. — 

 On the common periodicity of sun-spots and aurorse, by M. 

 Terby. (For the last four communications see Our Astronomical 

 Column.) — On the tensions of saturated vapours of different 

 liquids at the same pressure, by M. Edmond Colot. The ex- 

 periments made by the author bear out the law that between the 

 temperatures / and Q of the saturated vapours of any two liquids 

 which correspond to the same pressure, there exists the linear 

 relation / = A0 -^ B, where A and B are two constants, the 

 values of which depend on the nature of the liquids under con- 

 sideration. — On a standard condenser, by M. H. Abraham. 

 With a view of making a new determination of z^, M. Abraham 

 has constructed an air condenser having a capacity of about 500 

 in electro-static C.G.S. units. The arrangement is described, 

 and estimations are given of the probable accuracy which 

 can be attained. The ratio of the electro-static to the 

 electro-magnetic unit (v) has not yet been found.— On 

 electro-capillary phenomena, by M. Gouy. — On the mani- 

 festation of negative electricity during fine weather, by M. Ch. • 

 Andre. During fine weather a negative electrification of the 

 air is extremely rare. Several theories have been put forward 

 to account for this, but an examination of some of the records 

 of atmospheric electricity, made at the Lyons Observatory, leads 

 M. Andre to conclude that the appearance of negative electri- 

 fication during fine weather is an exaggeration of a diurnal 

 variation of which it is a particular case. — Crystalline absorp- 

 tion and the choice between the different theories of light, by 

 M. E. Carvallo. If a ray of monochromatic light traverse a 

 double-refracting crystal, the absorption only depends on the 

 position of the Fresnel vibration. The intensity of the emergent 

 ray is given by M. Becquerel's formula — 



sji = i>>JiQ{e~""' cos^a + ^-'"^cos-yS -f ^"^•''cos-y), 

 where ^o is the intensity of the incident ray ; i, the intensity of 

 the emergent ray ; a, fi, 7, angles between Fresnel's vibration 

 and the axes of optical elasticity ; x, the thickness of the 

 crystal traversed by the ray ; and e, the base of Naperian 

 logarithms. The author finds that this law is verified in the im- 

 portant case where only one of the three components exists It 

 also applies to heat rays. Finally, when an extraordinary ray 

 traverses tourmaline in a direction oblique to the axis, its 

 state of polarization varies progressively until the thickness 

 traversed is that which would destroy the ordinary ray. 

 This state then remains invariable up to emergence, when 

 the ray sharply regains the state of original polarization. — 

 On the determination of chemical equilibrium in solution systems, 

 by M. Georges Charpy. — Combinations of cuprous iodide with 

 ammonium thiosulphate, by M. E. Brun. The following com- 



NO. 



IT 70, VOL. 45] 



pounds have been obtained: CuoTg. 2NHJ . 8(NH4)<,S203 ; 

 4Cu„T2. CU2S2O3. 7(NH4)„S.,03- 4H.p;andCu2l2. (NH4)",S503. 

 IIjO. The author proposes to study similar compounds yielded 

 by sodium and potassium thiosulphates, and also compounds 

 given by other iodides, such as those of silver and lead. — Study 

 of the velocity of decomposition of diazo compounds, by MM. 

 J. Hausser and P. Th. MuUer. — Some bases homologous with 

 quinine, by MM. E. Grimaux and A. Arnaud.— The essence 

 oi Licari kanali, by M. Ph. Barbier.— Combinations of the fatty 

 acids with the ethylene series of hydrocarbons, by MM. Bthal 

 and Desgrez. — On the natural synthesis of the vegetable hydro- 

 carbons, by M. Maquenne. — On the presence, in straw, of 

 an aerobic ferment reducing nitrates, by M. E. Breal. — On the 

 hereditary transmission of acquired characters by Bacillus 

 anthracis under the influence of a dysgenesic temperature, by 

 M. C. Phisalix. — On the nitrogen in the blood, by MM. F. 

 Jolyet and C. Sigalas. — Anatomy of the hypogastric nervous 

 system of mammals, by M. Lannegrace. — On the Pliocene bird 

 fauna of Roussillon, by M. Ch. Deperet.— The sickle at the 

 end of the Stone Age, by M. Emile Cartailhac. — On the regime 

 of artesian wells in the El Golea region, by M. Georges Rolland. 

 — On a particular cause of contamination of water having its 

 source in limestones, by M. E, A. Martel. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Books. — Travels amongst the Great Andes of the Equator, and Supple- 

 mentary Appendix to ditto : \L. Whymper (Murray).— Diagram Illustrating 

 the Leblanc Soda Process, and Key to ditto: J. J. Miller (J. Heywood).— 

 Dictionary of Political Economy: Edited by R. H. 1. Palgrave, P.-irt 2 

 (Macmillan). — Bibliothek des Professors der Zoologie und Vergl. Anatomie, 

 1891 : Dr. L. von Graff (Leipzig, Engelmann).— The Universal Atlas, Part 

 13 (Cassell).— Le Climat de Rio de Janeiro: L. Cruls (Rio de Janeiro) — 

 The World and the Flood : A. J. Stuart (Shanklin). 



Pamphlet.— The French Peasantry since the Revolution of 1789 : L. 

 Notteile (Simpkin). 



Serials. — Quarterly Journal of Microscopical Science, No. 131 (Churchill). 

 — Bulletin de la Soci6t6 Astronomique de France, cinq, ann^e, 1891 (Paris). 



CONTENTS. PAGE 



A Zoologist on Disease. By Prof. E. Ray Lan- 



kester, F.R.S 505 



Two Books of African Travel 507 



Professor Tyndall's Latest Book. By J. D. E. . . 508 

 Our Book Shelf :— 



Roscoeand Schorlemmer: "A Treatise on Chemistry," 



Vol. III. Part VI 509 



Ward : " The Oak : a Popular Introduction to Forest 



Botany.'' — J. G. B 509 



Levett and Davison: "TheElementsof Plane Trigono- 

 metry " 509 



De Vilmorin : " Les Fleurs a Paris : Culture et Com- 

 merce " 510 



Buckland : ' ' Health Springs of Germany and Austria " 510 

 Letters to the Editor :- 



Heat-Engines and Saline Solutions. — Lord Ray- 



leigh, Sec.R.S 510 



On Earth Vibrations.— Dr. Emil Oddone . . . .-510 

 Striated Surface under the Cromer Drift. — William 



Sherwood 511 



Pilchards. —Matthias Dunn 511 



On theBoltzmann-Maxwell Lawof Partition of Kinetic 



Energy.— Rev. H. W. Watson, F.R.S 512 



The Functions of Universities. — Prof. Geo. Eras. 



FitzGerald, F.R.S 513 



A New Comet. — W. F. Denning 513 



On Insect Colours. I. By F. H. Perry Coste ... 513 



Notes 517 



Our Astronomical Column :— 



The Planet Jupiter 521 



The Objective Prism 521 



Variation of Latitude 521 



The Discovery of Neptune 522 



Astronomy at the Paris Academy, March 21 .... 522 



Variability of Nebulae . . 522 



Solar Prominence Photography 522 



The Aurora Spectrum 522 



The Properties of Amorphous Boron. By A. E. 



Tutton 522 



The Manchu Race 523 



Societies and Acadencies 524 



Books, Pamphlets, and Serials Received 528 



