504 



NATURE 



\JMarcJi 25, 1886 



its exact value and state of preservation is obvious. As the 

 same standard was used for the measurement of an arc of the 

 ]iieridian in Peru, it forms the connecting link between the older 

 and more recent geodetic operations. It thus becomes an object 

 nf the highest interest, not only for France, but for the whole 

 scientific world, and the author here replies in detail to the 

 doubts and objections that have been raised by Peters and others 

 in Germany against its authenticity and ^tate of preservation. 

 At his request the whole question will be submitted to a Com- 

 mission appointed for the purpose by the Academy, consisting 

 <jf MM. Faye, Mouchez, Janssen, F. Perrier, and Wolf. — 

 Memoir on the order in which the first vessels in the leaves of the 

 Cracifer.r make their appearance : mixed formation, and mor- 

 phogeny, by M. A. Trecul. The leaves of all the plants here 

 treated belong to one of the two types of mixed formation 

 described by the author in 1S53, that in which the lobes or 

 teeth of the lower part of the leaf are formed from above 

 downwards, while those of the upper part are developed in the 

 contrary direction from below upwards. — Theoretical considera- 

 tions on the principles affecting the roll of vessels at sea, in 

 connection with M. de Burry's recent communication [Compli-s 

 ;v;/,7/H of January 4, 1S86), byM. A. Ledieu. It is shown that M. 

 de Burry's conclusions cannot be accepted because based on do 

 Benaze and Risbec's formulas, which are applicable only to ships 

 in smooth water, account being taken of the resistance of the 

 keel. — Remarks in connection with the Bidlclin of the .Society 

 lor the Encouragement of National Industry, presented to tlie 

 Academy by M. Haton de la Goupilliere. — Note on the 

 hurricane that swept the Gulf of Aden in June 1885, by Vice- 

 Admiral Cloue. The cyclone, in which five large vessels 

 foundered, including the German corvette Augusta, and the 

 French aviso Le Kcnard, both with all hands, and in which 

 probably over Soo lives were lost, was especially remarkable 

 for its sudden appearance. As it penetrated up the Gulf, it 

 contracted from a diameter of 150 miles 250 miles east of 

 Socotra to 50 miles at Obock, increasing in velocity from S to 

 15 miles an hour. The diameter appears to have continued to 

 contract towards the interior of the continent, where it overtook 

 a caravan proceeding from Sangallo in the direction of Slioa. — 

 Remarks on the first botanical collections that have reached the 

 Paris Natural Historj' Museum from Tonquin (continued), by M. 

 Ed. Bureau. Although collected exclusively in the delta of the 

 Red River and surrounding hills, this flora includes no less than 

 407 species, distributed over 95 families. It comprises proliably 

 not a fourth of the whole flora of Tonquin, which thus appears to 

 be one of the richest in the world. — Note on the ephemcris of 

 Fabry's comet, by M. Lebeuf. — Complementaiy note on the 

 barometric depressions observed by M. Perrin on lioard 

 the Calissontiiirc m the Red .Sea, by M. Mouchez. — Simpli- 

 fications which may be effected in the numerical calcul.ation 

 of perturbations of planets, by M. O. Callandreau. — On 

 the latitudin.al distribution of the solar phenomena observed 

 during the year 1S85, by M. P. Tacchini. The general con- 

 clusions .arrived at are— (i) In 1885 the solar phenomena were 

 more frequent in the southern hemisphere ; (2) while the pro- 

 tuberances appear in e.ich zone, the spots, faculoe, and eruptions 

 are confined almost entirely to the regions between the equator 

 and ± 40°, one eruption and one facula alone being recorded in 

 higher latitudes; (3) the maximum of eruptions, spots, and 

 faculse occurs in the same zone of the southern hemisphere ; 

 (4) eruptions were less frequent in 1S85 than in 1884, which was 

 also true of the solar spots, showing the connection between 

 these two phenomena ; (5) the protuberances, on the contrary, 

 were more frequent in the zones where no spots occurred. — On 

 the theory of diversities in mathematical analysis, by M. 

 Lipschitz. — Note on the construction of the tangents to pl.ine 

 curves, and determination of the point at which a movable 

 straight line touches its envelope, by M. Rene Godefroy. — On 

 the determination of the coefficient of self-induction ; applica- 

 tion of the Deprez d'Arsonval aperiodic galvanometer, by M. 

 Ledeboer. — Application of the colour-diagram to experiments 

 m.ade on a colour-blind person, by M. Feret. — Descriptim 

 of a new apparatus for the quantitative analysis of o.\y- 

 genated waters (one illustration), by M. Maurice de Thierry. — 

 On selenides of sodium and of potassium, by M. Charles Fabre. 

 — On the formation and dissociation of manganates of baryta and 

 strontian, by M. G. Rousseau. The author had already shown 

 that, under temperatures increasing from dark red upwards, the 

 manganates of baryta and strontian become dissociated at a maxi- 

 mum of 1000° to 1100°, the limit being marked by the formation 



of a diamanganate, which at a still higher temperature returns 

 to the state of a monomanganite. He now finds that, by rais- 

 ing the temperature to a white heat, this manganite dis- 

 appears in its turn, passing to a maximum of oxidation 

 and becoming integrally transformed t j mang.anate. — On 

 the various degrees of solubility possessed by certain chlor- 

 ides in the presence of hydrochloric acid, by M. R. Engel. 

 — Description of various processes for the separation and quanti- 

 tative analysis of copper, cadmium, zinc, nickel, &c., by M. Ad. 

 Carnot. — On the existence of the elements of sugar of milk in 

 plants, by M. A. Muntz. Although hitherto rarely detected, it 

 is shown that these elements are found in great abundance in 

 plants, .and that the vegetable products yielding galactose are 

 very numerous. — On the decomposition of the sodico-ammoniacal 

 and sodico-potassic racemates, by M. G. Wyrouboff". — On the 

 seat of the organ of taste in the coleopterous insects, by M. J. 

 Gazagnaire. — On the labrum of the Hymenopter.n;, by M. Joannes 

 Chatin. — On the processes of fructification in the fossil calamo- 

 dendrons, by M. B. Renault. — Complementary observations on 

 the origin of the diamantiferous sands of South Africa, by M. 

 Stanislas Meunier. — On the eruptive rocks and stratified forma- 

 tions of the Serrania de Ronda system, south of Sp.iin, by MM. 

 Michel Levy and J. Bergeron. — On the optical properties of 

 griinerite, withamite, and some other minerals destitute of de- 

 terminable crystalline forms, by M. A. Lacroix. — On the 

 spectrum of the Ya earth, by M. W, Crookes. —On the mosan- 

 drine earth of Lawrence Smith, by M. Lecoq de Boisbaudran. 



BOOKS RECEIVED 



Turkestan," by J. Mochketon (St. Petersburg).— " The Statesman's 

 ir-Book, 1886," edited by J. S. Keltie (Macmillan and Co.).— 

 cientific Mem-irs by Medical Officers of the Army of India," part i., 

 ,i ('".il-i:tt:0 ■' Minutes of the Sixth Annual Convention of the Pro- 



;:' I : ! Association of Nova Scotia, July 15 and 16, 1885" 



!! : ■— "E.\isting Glaciers in the United States," by J. C. 

 ,1,1.. , ,,:i :. n)— "L'Evolutionet la Vie," by D. Cochin (G. Masson, 

 i-.^.— Hum ly Meteorological Readings, 1883," part iii., July to Sep- 

 ber). — "Christy's Guide 10 Poultry Rearing," new edition, by '!]. 

 isty. — " Annates del Museo Nacional de Buenos_ Aires. Entrega Deci- 

 " Segunda del toma iii., by German Rurmeister (Buenos Aires). 



CONTENTS p.\GE 



The Greely Arctic Expedition 481 



The Krakatao Dust- Glows of 1883-84 4S3 



Our Book Shelf:— 



Clark's " Star Guide " 483 



Shenstone's " Practical Introduction to Chemistry" . 484 

 Letters to the Editor : — 



Permanent Magnetic Polarity. — Prof. Oliver Lodge, 



F.R.S 484 



Dissociation and Contact-Action. — A. Irving . . . 485 



Variable Stars. — ^Jno. Castell-Evans 486 



The Iridescent Clouds and their Height.— Thos. W. 



Backhouse 486 



Forms of Ice. — Rev. George Henslow 486 



Sunrise-Glows. — R. T. Omond 487 



A Horrified Cat.— E. J. Dungate 487 



Nocturn.al Hymenopter.x' of the Genus Bonibits. — ^Jno. ^- 



C. ■Wilson 487 



A Linguistic Revolution 487 



The Survey of India, II 489 



Science Schools at Home and Abroad. By Prof. 



T. E. Thorpe, F.R.S. (IVil/i Plans) 491 



Jules Jamin. {IVilli Portrait) 493 



The U.S. Naval Observatory 494 



Notes 495 



Our Astronomical Column : — 



An Observation of Neptune occurring in Lamont's 



Zones 498 



The Armagh Observatory 49S 



Distribution in Latitude of Solar Phenomena . . . 498 



Prominences and Magnetic Disturbances 498 



Displacement of Lines in Solar Prominences .... 498 

 Astronomical Pnenomena for the Week 1886 



March 28— April 3 498 



The Sun and Stars, IV. By J. Norman Lockyer, 



F.R.S. (lUi/strated) 499 



Societies and Academies 5°2 



Books Received 504 



