1 5 8 



NA TURE 



[Dec. 1 8, 1884 



A Commission 1ms been appointed by M. Cochery to deter- 

 mine the conditions of security requisite for laying electric cables 

 to transmit currents of high tension. This step has been taken 

 in connection with the experiments conducted at Creil and the 

 Gare du Nord with the Marcel-Deprez system, as well as others 

 which may be in preparation. 



THE observer at the meteorological station on the summit of the 

 Obir (Carinthia) reports that on October II, at 8.15 p.m., he 

 saw a beautiful display of St. Elmo's fire. The points of the 

 vanes, the telephone wires, and the tops of the posts supporting 

 this wire shone brilliantly in a whitish-blue light. 



The additions to the Zoological Society's Gardens during the 

 past week include a Bonnet Monkey (Macacus sinicus ? ), a 

 Macaque Monkey (Macacus cynomolgus i ) from India, pre- 

 sented by Mr. John Roberts ; a Bonnet Monkey (Macacus sini- 

 cus i ) from India, presented by Mr. David McCance ; a 

 Montagu's Harrier (('. u ens), European, presented by 



Lord Lilford, F.Z.S. ; a Banded Gymnogene (Polyk 

 typicus) from West Africa, a Gold Pheasant (ThaumaUa picta 6 ) 

 from China, an Indian Python (Python molurus) from India, 

 deposited ; three Lions (Felts leo), born in the Gardens. 



OUR ASTRONOMICAL COLUMN 



The Binary Star a Centauri. — In the last number of the 

 Monthly Notices of the Royal Astronomical Society, Mr. E. B. 

 Powell, so favourably known for his excellent measures of 

 double-star-, made during his residence in India, has a note in 

 which he gives reasons for concluding that the period of revolu- 

 tion of this most interesting binary is longer than has 1 een 

 assigned by the later calculati ins of its orbit, and, instead of a 

 period of 77A years, which is about that found by Dr. Elkin, he 

 considers that one of S6 or S7 years is better supported by the 

 earlier observations, viz. those by Richaud at Pondicherry in 

 December, 1689, and I I Lima on July 4, 1709. The 

 results of an investigation by Dr. Doberck, communicated to the 

 writer early in 1S79, rather tend to support Mr. Powell's con- 

 clusion. Dr. Doberck's elements, which are professedly only 

 provisional- ones, are as follow : — 

 Periastron- passage 1875-12 



Node 



Angle between the lines of nodes and apsides 



Inclination 



Excentridty 



SenuVaxis major 



Period of revolution 



25 32 



45 58 



79 24 



•• 0-5332 



iS"'45 



3-536 years. 



In this orbit the angle and distance at the epochs of the observa- 

 tion of Richaud and Feuillee would be : — 



1689-95 ... Position, 14-9 ... Distance, 9-54 

 1709-51 ... „ 200-8 ... ,, 14-74 



Encke's Comet.— The elements of this comet for the ap- 

 proaching perihelion passage are as follow, according to the 

 calculations of Dr. O. Backlund of Pulkowa: — 



Perihelion passage 1885, March 76523 G.M.T. 



Longitude of perihelion 



,, ascending node 



Inclination 



Angle of excentricity 



Mean daily sidereal motion 



158 32 45-0^ Mean 

 334 3° 54'6 l Equinox 



12 54 o-i ) 1885-0 



57 45 20-5 

 i072"-973ii 



The corresponding period of revolution is 1207-86 days. An 

 ephemeris for January will appear next week. 



Barnard's Comet. — Prof. Frisby of Washington has calcu- 

 lated elliptical elements of this comet from observations made 

 at the Naval Observatory between August 12 and October 20, 

 and therefore extending over sixty-nine days. The period ol 

 revolution in his orbit is 1S7S65 days, or 5-143 years, but this 

 element does not appear to be as yet very closely determined, 

 much less so indeed than in the case of the second a 

 of short period detected during the present year by Wolf. In 

 Prof. Frisby 's orbit the distance of the comet at aphelion from 



the orbit of Jupiter would be 0-705, the aphelion distance being 

 4-683, therefore considerably within the orbit of the planet ; at 

 the ascending node the comet's distance from the sun would be 

 1-552, and at the opposite node 3-942. Taking these conditions 

 into account, it would appear probable that it has been long 

 moving in its actual orbit. The comet, however, belongs most 

 likely to the fainter class of those revolving in short periods, 

 and in the present year has been observed under somewhat 

 favourable circumstances : it approaches nearest to the earth 

 when the perihelion passage takes place between a fortnight and 

 three weeks earlier than in 1884. t in November 20, M. Perrotin 

 observing with the Gauthier-Eichens equatorial of the Observa- 

 tory of Nice, aperture o 3S111,, found the comet near the limit 

 of vision for that instrument; he remarks: — "four la rendre 

 sensible a l'ceil et bien saisir sa position exacte, on etait oblige 

 d'agiter legerement la lunette en ascen ion droite, tant"t dans 

 un sens, tantot dans 1 'autre. " The position determined for that 

 evening was as follows : — 



Nov. 20 at 7I1. 25m. 38s. Nice M.T. R.A. 22I1. 38m. 21-855., 



N.P.D. 97 iS' 20-4''. 



The Observatory of Nice (Mont Gros), established through 



the munificence of M llis..ho|i,h,nin of Paris, is in longitude 



oh. 29m. I2'2s. east of 1 Ireen rich, and inlatitude 43 43' t&'"J. 



GEOGRAPHICAL NOTES 

 The correspondent of the Times with the Afghan Boundary 

 Commission, writing from Khwaja Ali on October 16, describes 

 the march of the expedition from Quetta to the Helmand. 

 The geologist, Mr. Griesbach, describes the geological features 

 of the country as much the same as those seen in the Pishin and 

 Candahar country, viz. steep, deeply-eroded mountain ranges 

 with a general strike of north, south to north-east, south-west, 

 the intervening valleys being filled by Post-Tertiary deposits, 

 which form extensive plains and glacis. The ranges of hills 

 are more or less continuations of ranges, which are crossed by 

 the Quetta-Candahar road. After leaving Kanak, one crosses 

 the south-western end of the Ghaziaband range, which is com- 

 posed of sand one, rid grits of the " flysch " facies of 

 the Eocene rocks. Beyond that range one enters the southern ex- 

 tension of the Lora plain of the Pishin. The white and coloured 

 clays of the Siwaliks, seen from Dina Rare.: in the Pishin, are 

 again seen (afar off ) from Panjpai, and no doubt they underlie 

 most of the Post-Tertiary deposits which form the surface of 

 these wide valleys). The low ridges between Panjpai and Nushlci 

 are composed of sandstones, flaggy limestone beds, and friable 

 shale, identical with the " Sohman " sandstone, and entirely 

 belonging to the Lower Cretaceous series. The contact between 

 the hippuritic limestone and the trap contains in the Candahar 

 district gold (with traces of nickel) and galena ores. The water 

 found below the surface is the natural drainage from the hills, 

 contained in the gravels and sands of the Post-Tertiary fan 

 ; 1 closed bi 1 ween the clays of the Siwaliks below, and 

 the recent conglomerate (a kind of kankar) above. 



Dr. Chavanne, who visited the Congo by order of the 

 :1s Geographical Society, has returned to Lisbon for a 

 short period in order to recruit his health, which has suffered by 

 the tropical climate. — Herr Flegel, who was preparing for a 

 ion into the Benue districts, is also detained in 

 Europe by ill health. — The Russian traveller, M. Piasecki, well 

 know 11 through his travels in China in 1S74, is about to start on 

 another exploring expedition to that country under the patronage 

 of the Emperor of Russia and the ( band Duke Wladimir. 



In a recent number of the Revue Scienlijique there is a long 

 article by M. L. Siinonin, on the geography of China. The 

 area of the whole Empire of China is estimated at 11,574,356 

 square kilometres, i.e. the la; in the world next to 



that of Russia, which is 21,702, 230 square kilometres. China 

 . however, is only 4,024, 690 square kilometres, i.e. two- 

 fEui n times the size of France, and fifteen times 



that of Great Britain. With regard to the population of China 

 it is not possible to give precise and absolutely trustworthy 

 numbers, there being no proper official census in force in the 

 Empire. The statistician of the Imperial Chinese Custom ets 

 down the actual population of China at 250,000,000. A census 

 drawn up in 1SS2 for fiscal purposes, and cited by the United 

 States Minister in China, gives 255,000,000 as the number of 

 the population. In the lower basin of the Vang-tse-Kiang as 



