520 



NA TURE 



{Sept. 21, 1882 



lyptus which had been lately rediscovered by his brother, Mr. 

 T. Stephens, in the immediate neighbourhood of Hobart. He 

 stated that the plant {Eucalyptus cordata) had only once been 

 seen by botanists since the expedition of d'Entrecasteaux, and 

 then only in two isolated and remote spots. 

 Paris 

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

 chair.— The following papers were read :— Solution, in finite and 

 simple term-, of the problem of longitudinal shock, hy any body, 

 of an elastic bar fixed at the unstruck extremity, by M. de Saint 

 Venant.— On the figure of comets, by M. Faye. In this whole 

 question, apparently so complicated, there is merely (he says), 

 the play of solar attraction tending to decompose bodies of very 

 small mass and large volume, and that of solar repulsion (due to 

 incandescence) which begins to act on the evaporable part of 

 those materials, when, freed from all pressure and subject to 

 increasing heat, they commence to form nebulosities of excessive 



rarity. On trombes observed on the sea at Etrctat, by M. 



Lalanne. The phenomena described, comprising deven trombes, 

 occurred in September, 1851. M. Faye explains them on his 

 theory.— On the distribution of heat in the dark regions of solar 

 spectra, by M. Desains. He gives here his observations with 

 pri-ms of crown-glass and flint (the previous were with rock-salt). 

 The spectrum is prolonged much further on the side of the rays 

 of great wavelength, than with rock-salt. M. Desains describes 

 ah apparatus, for determining, conveniently and surely, the 

 angular distance of any line of the luminous spectrum from one 

 of the cold bands of the dark spectrum.— M. Alph. Milne- 

 Edwards announced that the Trauaillcur had returned from its 

 cruise in the Bay of Biscay, to the west of Spain and Morocco, 

 to Madeira and the Canaries.— Typhoid fever in Paris ; period 

 of 1875 to 1SS2, by M. de Pietra-Santa. In the first half of 

 this year the deaths from typhoid fever in Paris were 4 - 6o per 

 cent, of the total deaths (in 1865-7 they were only 1-90 per cent., 

 in 1S75, 2-30 per cent.). The fever has most victims in April 

 and in November. Its distribution is unequal in the several 

 arrondissements. There is no direct and constant relation be- 

 tween the number of deaths from it, and the number of the 

 population in the arrondi-sement, the surface, the density of 

 population, and the general mortality. Medical statistics, with 

 clinical observation, prove the impossibility of referring typhoid 

 fever to a single cause, the fecal origin asigned by the English 

 school.— Theoretical and practical consideration on the phe- 

 nomena of electro-magnetic induction; application to the 

 more common types of machines, by M. de Tromelin.— 

 Action of helenine on the bacillus of tuberculosis, by M. de 

 K rab. Helenine seems adverse to the development of the 

 organism.— Ob the svphilitic bacterium ; syphilitic development 

 inlhe pig, by MM. Martineau and Ilamonie.— On the problem 

 of Kepler, by M. de Gasparis.— Oscillation-balance employed 

 for calculation of moments of inertia, by M. Brassinne.— Re- 

 searches on the absorption-spectrum of the terrestrial atmosphere, 

 by M. Egoroff. These were carried out at the Paris Observatory 

 with M Fhollon, the electric and other light being sent from 

 M<.nt Valerien, Mnntsouris, &c. Details .if the spectra are 

 given —Experimental study of the reflection of actinic rays; 

 influence of specular polish, by M. de Chardonnet. Every sur- 

 face reflects in variable proportions each of the spectral radia- 

 i i The reflecting power of a liquid is independent of the 



substances it holds in solution or suspension. Specular polish 

 increases the total quantity of radiations reflected, while the 

 relative intensity of different regions of the spectrum depends on 

 the matter employed.— On the law of cooling, by M. Riviere. 

 He observed the cooling of a platinum wire heated by an electric 

 current in dry air, within a glass cylinder, on which flowed a 

 current of cold water. The wire's temperature was deduced 

 from the variations of its conductivity, and the quantity of heat 

 lost (equal to that developed by the current), calculated by 

 Toule's law. The results are compared with those got from the 

 formulae of Pulong and Petit and of Rossetti. (The formula of 

 the former is shown, as by other physicists, to give too rapid 

 increase.)— On the law of thermal constants of substitution, by 

 M Tommasi. — On some combinations belonging to the group of 

 creatinines, by M. Duvillier.— Researches on the circulatory 

 apparatus of 'regular sea-urchins, by M. Kcehler.—On the 

 innervation of the mantle of some lamellibranch molluscs, by 

 M. Vialleton.— On the intestinal parasites of the oyster, by 



M. Certes. _ , 



September 11.— M. Blanchard in the chair.— Reference was 

 made to the death of M. Liom-ille, Member, and M. Planta- 



mour, Correspondent. (Funeral discnurses on the former, by 

 MM. Faye and Laboulaye, are printed in Compits Reudus). — On 

 the mean temperature of the northern and southern hemispheres 

 of the earth, by Mr. Hennes-y. There is reason to believe that 

 the idea of a superiority of temperature of the northern hemi- 

 sphere over that of the southern must be given up. Mr. Henel 

 considers the southern hemisphere,, with its greater mass of 

 water, to have (if anything) the higher temperature, or about 

 15° 4 C. Herr Hann considers that I5°'2 C. represents the tem- 

 perature of both hemispheres. Mr. Hennessey views with satis- 

 faction the removal of a difficulty in his theory of climates put 

 forth many years ago. — On the extension of the phylloxera at 

 Beziers in vineyards not submitted to treatment, by M. Henne- 

 guy. — Means of combating the disease of the vine, by M. 

 Maistre. He has had good results from applications of greasy 

 water (from washing of sheep's wool) every fifteen days, besides 

 sulphocarbonate of potassium. — Conditions for two linear differ- 

 ential equations without second member to have/ common solu- 

 tions ; equations giving the solutions, by M. Lemonnier. — Natural 

 definition of differential parameters of functions, and especially of 

 that of the second order A 2 , by M. Boussine-q.— Observations 

 of the solar spectrum, by Mr. Langley. '1 his relates to the 

 resnlts of the Mount Whitney expedition. Inter alia, it is esti- 

 mated, that, our atmosphere apart, the solar rays would raise 

 about 3 deg. C. I gr. of water in one minute, for each square 

 centimetre of the earth's surface exposed normally to them. Of 

 the total energy which vivifies the world, only a quarter 

 occurs in the visible spectrum and the ultra-violet ;• the other 

 three quarters exist in the great infra-red region, whose exten- 

 sion has been so erroneously conceived. The general telluric 

 absorption, at least in dry climates, diminishes to the extreme 

 infra-red. In general, in both atmospheres (the earth's and the 

 sun's), the absorption increases (except in interruptions noted) 

 as the wave-length diminishes. The absolute colour of the 

 photosphere is blue. The maximum energy in the visible spec- 

 trum is in the orange. — On the various causes of etiolation of 

 plants, by M. Mer.° He inquires into these by a comparison of 

 the phenomena of aquatic plants with those of aerial plants grown 

 in the dark or in moist air. — On a new amputation of an upper 

 limb, by M. Despres. For disease of the omoplate this bo»e 

 was removed, with the arm and part of the clavicle.— Signor 

 Govi presented a small work giving six unpublished letters of 

 Galileo ; also a memoir describing experiments in transforma- 

 tion of electricity of tension into voltaic currents. The latter 

 were made in ignorance of the previous experiment 

 Bichat. With a small Holtz machine Signor Govi dec 

 water, getting in three minutes 1 cc. of explosive mixture ; with 

 the same current he vibrated a Froment siren, produced magnetic 

 spectra, obtained very bright sparks by interruption w ith a steel 

 file, lit an arc between cartons, and actuated a Rhumkorff coil. 



CONTENTS Page 



Psychological Development in Children. By Dr. Gsorce J. 



Romanes, F R.S ** 



Sclater's "Jacamars and Puff-Birds «9 



' K Rad°HnVs EI " illustrated Essay on the Noctuida: of North 



America, with 'a Colony of Butterflies" 5»° 



Stack's "Six Months in Persia."-A. H. Keank . ... • • 5°° 



Vinters "Notes on Chemical Calculations, with Examples . . 5°i 



Miss Ridley's " Pocket Guide to British Ferns 5°i 



L.ETTERS TO THE EDITOR 1 — _ _ _ .-, t> 



A Meteorological Spectroscope. -Col. J. F. D. D0NHB1.LV, C.B.. ^ 



The New Comet- A. A. Common ■■ ■ ■ ■ • ^ • J. • J so1 

 Contact Makers of Delicate Action.-Prof. S. H. Hsle Shaw 



(With Illustration) . ■■■••• *" 



Bobbers.— Prof. H. N. Moselby, F.R.S 5°i 



Professor Haeckel in Ceylon, V. . •• 5 



A Solar Printing Press MM Illustration) ■ ■ ■ ■■■ ■ • S°3 



Notes on theAye-Aye of Madagascar. By Rev k I'-vron ■ . 504 



The American Association for the Advancement of Science . 505 



^Tf WiLLi^r T U homson's Graded Galvanometers'. 'By 



Andrew Gray (With Illustrations) !.'.".' 509 



Notes 



Our Astronomical Columu : — 



Cometary Discoveries •■••••• ,,- 



1 he Total Solar Eclipses of 1883 and 1885 m 



vS^SSbSSS^. a\nd How to'Read it.' By John' Evans'. ^ 

 Reck" £« » TeSShoWv! By W.lliam Henry -Preece, 



F.R.S '.'.'.'. SU 



Scientific Serials _ '^ z g 



Societies and Academies 



