July 30, 1891] 



NATURE 



311 



saturated vapour. He has reduced the difficulties of the prob- 

 lem to the evaluation of certain definite integrals. — Dr. John 

 Murray communicated a paper by Mr. J. W. Gregory, of the 

 British Museum, on the Maltese fossil Echinoidea, and their 

 evidence on the correlation of the Maltese rocks. In this 

 paper the fossil Echinoidea of Malta are revised, and many 

 additions to ihe fauna made by the description of material 

 recently collected. Several genera new to Malta are recorded, 

 and also some species previously known only in Italy. Some 

 changes in nomenclature are advocated : thus, as the author 

 accepts the zoological use of the generic name Echinanthus, a 

 new one — Breynella — is proposed for the genus known to 

 palaeontologists by the former term. In regard to the age of the 

 Maltese beds, the author agrees with Fuchs as to the Lower 

 Coralline limestone bein^ clearly Oligocene ; the overlying 

 Globigerina limestone is assigned partly to the Aquitanian and 

 partly to the Langhien : as no sharp line of division can be 

 drawn between these two series, the exact limits of the Oligo- 

 cene and the Miocene in Malta cannot be precisely determined. 

 The blue clay appears also to belong to the Langhien, and to be 

 hardly entitled to separation from the underlying Globigerina 

 limestone ; the greensand is referred to the Helvetian, and the 

 Upper Coralline limestone to the Tortonian. The relations of 

 Echinoid faunas of the different horizons to those of the corre- 

 sponding beds in other parts of the Mediterranean are considered, 

 and it is argued that deep-sea conditions prevailed in different 

 areas at different times : hence they show merely a series of 

 local subsidences, instead of one great regional depression. — 

 Prof. Ewart communicated the first part of a paper on the 

 lateral sense-organs of Ltemargiis and Acanthias, in which he 

 dealt specially with the sensory canals. — Prof. Tail communi- 

 cated a paper, by Prof. C. G. Knott, on the electric resistance of 

 cobalt at high temperatures. The cobalt on which Prof. Knott 

 experimented was in the form of a thin strip cut from a sheet in 

 the possession of Prof. Tait. The metal was very pure — con- 

 taining possibly I per cent, of carbon, 0"l5 per cent, of 

 silicon, 073 percent, of iron, a very small percentage of man- 

 ganese, and perhaps o"i percent, of an undetermined metal. 

 The formula r = ae*', where r is the resistance and i is the 

 temperature, closely represents the results at temperatures above 

 100 C. This law is identical with that which holds in the case 

 of nickel, but the rate of variation is not so great in cobalt as it 

 is in nickel. When first heated to a very high temperature, 

 profound changes take place in the metal as regards its change 

 of resistance with temperature. The metal resembles nickel and 

 iron in that the rate of variation of its resistance increases rapidly 

 as the temperature rises. But, in nickel and iron, at a still 

 higher temperature, this is followed by a distinct decrease. No 

 such effect is observed in cobalt. — Prof. Tait also read a paper, 

 by the same author, on the thermo-electric positions of cobalt 

 and bismuth. A triple junction of cobalt, bismuth, and palla- 

 dium was used. A rod of bismuth was formed by breaking 

 the metal into small pieces, and packing them into a siphon- 

 shaped glass tube. Gentle heating fused the pieces, and so a 

 solid rod was formed. The other wires were fused into its ends. 

 The line of this specimen of cobalt, on the thermo-electric 

 diagram, lay, at ordinary temperatures, above that of the 

 specimen of nickel which Prof. Tait used in the construction of 

 the diagram, but a neutral point existed at ICX3°, because of the 

 greater steepness of the cobalt line. The slope of the line is the 

 tjreatest which has yet been observed, with the exception of that 

 of the upwardly-sloping portion of the line of nickel. The 

 thermoelectric power of bismuth does not alter in strong mag- 

 netic fields, although Righi has shown that its resistance alters 

 in such fields. 



Sydney. 



Royal Society of New South Wales, May 13. — Civil 



L^ineering Section Meeting. — Mr. C. W. Darley in the chair. 



ihe inaugural address was delivered by the Chairman ; and a 



paper read on researches in iron and steel, and working stresses 



in structures, by Prof. Warren. 



June 3. — Mr. W. A. Dixon, Vice-President, in the chair. — 

 Six new members were elected.— The following paper was 

 read : — Notes on the large death-rate among Australian sheep in 

 country affected with Cumberland disease or splenic fever, by 

 M. Adrien Loir, Director of the Pasteur Institute of Australia. — 

 I'rof. Anderson-Stuart exhibited his new instrument for demon- 

 >trating the manner in which sound-waves are propagated ; and 

 Lovibond's tintometer was shown by the Chairman, 



NO. II 35, VOL. 44] 



Paris. 



Academy of Sciences, July 20. — M. Duchartre in the chair. 

 —The life and works of the late Prof. W. Weber, by M, 

 Mascart. — Observations of minor planets, made with the great 

 meridian instrument of Paris Observatory during the second 

 half of 1890 and the first quarter of 1891, by Admiral Mouchez. 

 The asteroids which have been observed for position are : 



©, ©, ©> ©. ©. ®. ©, ®, ©> ©> ®. 

 ®. ©• 



— The third meeting of the International Committee of the map 

 of the heavens : presentation of the Proceedings, by the same 

 author. — Elements of the elliptic comets Swift (1889 VI.) and 

 Spitalier (1890 VII.), by Dr. J. K. Hind.— Evidences that 

 Europe and America have been united during recent times, by 

 M. Emile Blanchard. The evidences given in the author's 

 memoir are derived from a discussion of the fauna and flora of 

 the two continents. — On the glycolysis of circulating blood in 

 living tissues, by MM. R. Lepine and Barral. The authors' 

 method of studying the glycolysis of blood in circulation in an 

 isolated member appears to be more exact than that of studying 

 it in vitro. They have used it to prove the diminution of 

 haematic glycolysis that occurs in experimental diabetes. — 

 Apparent total disappearance of lupiter's satellites, by M. C. 

 Flammarion. On July 15, M. Flammarion observed Jupiter 

 when three of his satellites were passing across his disk 

 and one behind it. This rare phenomenon occurs every 

 twenty-three years, a period which contains 523 revolu- 

 tions of the fourth satellite, 1220 of the third, 2488 of the 

 second, and 4934 of the first. It was first put on record 

 by Galileo in 161 1, and M. Flammarion gives a list of seven 

 other observers who have noted it. — Experiments on weirs, by 

 M. H. Bazin. — Vibration of a wire along which an electric cur- 

 rent is passing, by M. D. Hurmuzescu. A metallic wire 

 stretched between two supports and traversed by an electric 

 current sets itself in vibration. The amplitude of the vibrations 

 steadily increases and reaches a maximum, which is maintained 

 so long as the current is passing and no changes occur in the 

 conditions of the surrounding medium. For a given tension, 

 the amplitude appears to depend on the difference of tempera- 

 ture of the wire and the medium in which it vibrates ; hence it 

 varies as the intensity of the current. — The absorption and 

 photography of colours, by M. Labatut. Using M. Lippmann's 

 method for the photography of the spectrum in its colours, the 

 author has investigated the absorbing action of screens coloured 

 with dyes, such as cyanin, &c. , in relation to the parts of the 

 spectrum impressed on the prepared plate and the interference 

 colours produced. — On the composition of atmospheric air : 

 new gravimetric method, by M. A. Leduc. The following 

 represents the results obtained in two experiments : — 



Grms. Grms. 



Weight of air analysed 3'4237 ••• 3'55S' 



Weight of oxygen which combined with 



phosphorus ... 07958 ... o8249- 



Percentage proportion of oxygen 23 "244 ... 23-203 



The mean of these values is 23*224, or, roughly, 23 "23, which 

 may therefore be taken to represent the percentage of oxygen in 

 purified air. The composition by volume is stated as : nitrogen 

 78-98 per cent., and oxygen 2 1-02 per cent. — On silicon selenide, 

 by M. Paul Sabatier. This body has been prepared by passing 

 a current of dry hydrogen selenide over crystallized silicon at a 

 red heat. The selenide obtained is a hard substance, having a 

 semi metallic appearance, and apparently not volatile at the 

 temperature of the experiment. Its composition, verified by 

 several analyses, is represented by the formula SiSea. — Melting- 

 point of certain organic binary systems (hydrocarbons), by M. 

 Leo Vignon. — Study of the solid products resulting from the 

 oxidation of drying oils, by M. A. Livache. — On a new 

 method of testing for phenol, by M. L. Carre. — On ozone con- 

 sidered from a physiological and therapeutical point of view, by 

 MM. D. Labbe and Oudin. — On the mode of action of the 

 butyric ferment in the transformation of starch into dextrine, 

 by M. A. Villiers. — On a toxalbumin secreted by a microbe 

 from blennorhagic pus, by MM. Hugounenq and Eraud. — Oscil- 

 lations of the retina, by M. A. Charpentier. The author has 

 studied experimentally certain phenomena ."which appear to 

 demonstrate the production of oscillations in the visual organ 



