5 o8 



NATURE 



{March 25, 1880 



leaden block in the same manner as the vanes of a radiometer 

 are repelled from the relatively cool sides of the surrounding 

 class envelope. — 2. On the effect of temperature on the illuminat- 

 ing power of coal-gas. — On a new harmonic relation between 

 the lines of hydrogen, by G. Johnstone Stoney, D.Sc, F.R.S. 

 The author pointed out that the stellar line H ]? which Mr. 

 i s investigations show to be probably a hydrogen line, 



stands in a simple harmonic relation with the known hydrogen 

 line near G ; U 1 being the 35th, and the line near G the 

 32nd, harmonics of a vibration the periodic time of which is 

 T _l. 72x03, where t is the time that light takes to advance a 

 millimetre in air. The other known hydrogen lines, viz., C, F, 

 and h, are already known to be the 20th, 27th, and 32nd har- 

 monics of another vibration the periodic time of which is 

 T jl. 76'2. — Natural Science Section, with which the Royal 

 Geological Society of Ireland is associated. — G. H. Kinahan, 

 M.R.I. A., in the chair. — The Chairman, as president of the 

 Royal Ge logical Society of Ireland, delivered the anniver- 

 sary address.— V. Ball, M.A., F.G.S., read a paper on the 

 evidence in favour of the existence of floating ice in India 

 during the deposition of the Talchir (Permian) rocks. In this 

 communicati .11 the author gave a risumi of the facts which are 

 held by Indian geologists to prove that during a part of the 

 Talchir period the climate of Peninsular India was sufficiently 

 cold, during the winters at least, to cause the formation of land- 

 ice on the margins of the great lakes which then existed. The 

 fact- are imilar to those employed to establish the glacial 

 period of Europe. There is a boulder-bed which contains huge 

 masses of rock enveloped in fine silt. In some cases it is de- 

 mon srrable that these boulders have been carried from long 

 distances in a direction contrary to the present slope of the 

 surface. In others, but less commonly, polished and striated 

 boulders have been found resting on scored and striated surfaces. 

 The fossils of the Talchir rocks, consisting of a few ferns and 

 equisitaceae— all previous periods having been azoic — are not 

 inconsistent with a mild, temperate climate. Reference was 

 made by the author to the Karroo beds of South Africa and the 

 Permian breccias of England, which are likewise believed to 

 have had a glacial origin. 



Paris 



Academy of Sciences, March 15. — M. Ed. Becquerel in the 

 chair. — The following papers were read : — On a particular deve- 

 lopment of the perturbative function, by M, Tisserand. — On the 

 compensation of temperatures in chronometers, by M. Phillips. — 

 On the hypothesis of Laplace, by M. Faye. He shows the 

 adverse bearing of various modern discoveries on it. — Reply to 

 M. B ill eli it's observations on hydrate of chloral, by M. Wurtz. 

 — Action of oxygenated water on oxide of silver and on metallic 

 silver, by M. Berthelot. Oxygenated water forms with silver 

 oxide, in equal equivalents, a first unstable compi u id, 

 Ag„0.,3lI0 2 , with separation of metallic silver. This is almost 

 immediately dec imposed into hydrated sesquioxide, water, and 

 oxygen — with liberation of heat. If the silver oxide is in exec s 

 the action ends there ; but if there is an excess of oxygenated 

 water the sesquioxide acts in its turn on this, reproducing 

 Ag 2 O s 3HOj, which is again decomposed, and so on, till total 

 11 of the oxygenated water. The same theory accounts 

 for the decomposition of oxygenated water in contact with 

 metallic silver. — Memoir on the temperature of the air at the 

 surface of the ground and to 36 m. depth, also on the temperature 

 of two pieces of ground, one bare, the other covered with s id, 

 during 1S79, by MM. Becquerel. The results seem mainly to 

 confirm those of previous observations. — Present state of 

 the question as to the interoceanic canal ; letter from M. 

 De Le-seps to M. Larrey. He gives, among other news, a 

 local account of the recent earthquake at San Salvador. — 

 On a microphonic apparatus receiving speech at a distance, by 

 MM. Bert and D'Arsonval, They use a plate of hardened 

 rubber, through which passes the fixed carbon. The other carb m 

 is carried by an iron rod which can turn about an axis, and whose 

 mobility is regulated by a movable magnet. When the magnet 

 is distant, the rod can turn on its pivot indifferently, but in the 

 opposite ca-e it is strongly directed, giving vibrations of very 

 small amplitude and great rapidity. Speaking loudly at 4 or 

 5 m. from this instrument (or with low voice near), the speech is 

 distinctly transmitted. — Practical rules for the establishment of 

 telodynamic transmissions, by M. Leaute. — On the economic 

 product of electric motors, and on measurement of the quantity 

 of energy which traverses an electric circuit, by M. Deprez. — 

 Laws concerning the distribution of the stars of the solar system, 



by M. Gaussin. Three more are given. — On the systems formed 

 of linear equations with a single independent variable, by M. 

 Darboux. — On the reduction of linear" substitutions, by M. Jordan. 

 — On the equation with partial derivatives of potential, by M. 

 Picard. — On a new telemeter, by M. Landolt. This is based on 

 the principle of refraction through a prism of variable angle, 

 composed of two elementary prisms of the same power turning 

 one on the other with the same velocity in opposite directions. 

 The two have a central aperture concentric with the axis of 

 rotation, and equal to half the surface of section of the bundle of 

 luminous rays which enters the eye. The observer thus looks at 

 once through the apertures and through the prisms. In one posi- 

 tion of the prisms the object is seen simple, but on turning it is 

 doubled, and from the amount of rotation necessary to bring 

 the two images to a given position, the distance may be deduced. 

 The instrument serves also for measurement of the size of inac- 

 cessible objects. — Application of the telephone to measuring the 

 torsion of the motor-shaft of engines in motion, by M. Resio. 

 Two similar copper wheels with equidistant palettes are fixed 

 on the shaft, and turn before the core-ends of two similar bob- 

 bins wound oppositely, the wire forming part of a telephone 

 circuit. While there is no torsion and the palettes therefore 

 pass the cores simultaneously, the telephone is silent ; but torsion 

 makes it sound. By displacing the second bobbin on a gradu- 

 ated circle, silence is again had, and the amount of torsion can 

 be estimated. — On a process for the measurement of high tem- 

 peratures, by MM. Crafts and Meier. This is an adaptation of 

 the gas- thermometer. — Electrolysis of malonic acid, by M. Bour- 

 goin. — Synthesis of ulmic matters, by M. Millot. — On the pro- 

 ducts of decomposition of proteic matters, by M. Bleunard. — 

 On the anatomical characters of the blood in phlegmasia, by M. 

 Hayem. — On the digestive action of the juice of 1 apaya and of 

 papaine on the sound or pathological tissues of the living being, 

 by M. Bouchut. All organised tissues, even when living, may 

 be peptonised by this substance (papaine), which is the vegetable 

 peptone. — On anchylostomiasis, by MM. Concato and Perroncito. 

 — On the artificial production of felspars with base of baryta, 

 strontia, and lead, corresponding to oligoclase, labradorite, and 

 anorthite, by MM. Fouque and Levy. They operated by pro- 

 ducing crystallisation at a high temperature, below the point of 

 fusion, but near it. — Eruption and fall of volcanic dust at 

 Dominica on January 4, by M. L. Bert. Inter alia, the cloud- 

 carrying dust is shown to have travelled very slowly, though 

 the wind was high. — Examination of the volcanic dust (just 

 referred to) and the water which accompanied them, by M. 

 Paubre'e. The presence of innumerable crystals of pyrites in 

 the powder is specially notable ; also the presence of galena. — 

 Separation of minerals whose density is greater than that of 

 quartz with the aid of fused mixtures of chloride of lead and 

 chloride of zinc, by M. Breon. — Apercu on the genesis of the 

 mineral waters of Savoy, by M. Levy. — Composition of the 

 mineral waters of Lussang (Vosges), by M. Willm. 



CONTENTS Page 



The Institution of Naval Architects 4S5 



The Local Endowment of Research 487 



Eclipse Observations. By Dr. Arthur Schuster, F.R.S. . . . 4^8 



Nicholson's Tabulate Corals 4.0 



Lettrrs to the Editok : — 



Dissociation of Metalloid Elements.— Sir B. C. Brodie, Bart. . . 491 



The Aurora at Last.— Prof. Piazzi Smyth 492 



A Museum Conference.— Academicus ; E. Howarth .... 491 

 A Method of Calculating the Expansion of a Substance on 



Vaporisation.— W. J. Sollas 49 2 



A Claim for Precedence.— Thomas Woods 493 



The Origin of Man.— W. S. Duncan 493 



TheStnne in the Nest of the Swallow.— Dr. P. P. C. Hoek . . 494 



Carnivorous Wasps. — R. S. Newall, F.R.S 494 



Intellect in Brutes.— A. M 494 



Diatoms in the London Clay.— W. H. Penning 494 



Visualised Numerals. By Francis Galton, F.R.S 494 



The Telephonic Exchange in the United States (With Illus- 

 trations) 495 



An Am rican Sea-Side Laboratory. By Prof. E. RayLankester, 



F.R.S 457 



The Solubility of Gases in Solids 459 



The Late Mr. Thomas Bell, F.R.S 459 



Notes . . S«> 



Our Astronomical Column: — 



Suspected Variable Stars 5°» 



The Southern Comet S02 



Meteorological Notes 5°3 



Physical Notes 5C4 



Geographical Notes 5°4 



University and Educational Intelligence 5o3 



Scientific Serials 5°| 



Societies and Academies 3c- 



