44 8 



NATURE 



\_August 31, 1882 



which was accepted by those present, a sum of money being 

 subscribed for the purpose. 



The additions to the Zoological Society's Gardens during the 

 past week include a Campbell's Monkey ( Cerccpilhecus campbelli), 

 a Diana Monkey (Cereopit/nrus diana) from West Africa, pre- 

 sented by the Rev. C. Harris; a Wool Brocket (Cariacus 

 nemorivagus), a Hairy Armadillo {Dasypus zillosus) from Brazil, 

 presented by Mr. C. A. Craven ; a Cariama (Cariama cristata) 

 from Brazil, presented by Capt. Jones, H.M.S. Garnet; four 



Frogs ( sp. inc.) from Dominica, presented 1 y Mr. 



E. Scrutton ; a Greater Sulphur-crested Cockatoo [Cacatua 

 galerita) from Australia, deposited ; a Weeper Capuchin (Cebus 

 faliie/liis) from Guiana, two New Zealand Parrakeets (Cyano- 

 rJiamphus nava-aalanduc], two Alpine Parrakeets (Cyanorham- 

 phus alpinus), two Golden-headed Parrakeets (Cyanorhamphus 



aurieeps), two Parrakeets (Cyanorhamphus, sp. inc.) from 



New Zealand, two Peruvian Thicknees ( CEdicnemus superciliaris) 

 from Peru, four Common Kingfishers [Alcedo isptda), British, 

 purchased ; a Cape Zorilla (Ictonyx zorilla) from South Africa, 

 received on approval. 



OUR ASTRONOMICAL COLUMN 



The Cluster TH.-ESErE. — At the sitting of the Academy of 

 Sciences of Paris on the 14th inst., a paper was presented bj M. 

 Wolf, giving a description of this well-known star-cluster, and 

 micrometric measures of the relative positions of its principal 

 components. M. Wolf made use of the same methods and 

 instruments of the Observatory at Paris which he had employed 

 in 1873-75, in his elaborate scrutiny of the Pleiades. His work 

 . i) I1.1 iepe comprises three sections : I. the micrometric de- 

 termination of the relative positions of its principal stars, to the 

 number of 82, with the filar-micrometer used in 1S73-75. The 



of the 82 stars are given relatively to e Cancri, and are 

 reduced to the beginning of the year 1S77, for which epoch the 

 place of the reference star is in R.A. Sh. 33m. 23S.75, N.P. D. 

 70 l' lS"'o; these stars are between the seventh and eleventh 

 magnitudes. II. The micrometric determination of the relative 



of all the Stars in the group to the twelfth magnitude 



I in a rectangle of eight minutes of time by ninety 

 minutes of arc, these determinations being made with the micro- 

 meter constructed by M. Wolf for the rapid registration of 

 groups of stars, the places being given to a tenth of a minute of 

 arc by reference to the accurate positions of section I. ; this 

 second catalogue includes 1S8 stars. III. A revision by actual 



n with the sky of the chart of positions so formed, and 

 the insertion of stars omitted or lower than the twelfth magnitude ; 

 the chart thus completed contains 363 stars. 



Unfortunately there are few ancient observations for com- 

 parison. The Memoirs of the Academy of Sciences (first series) 

 contain two charts of the clusler, one formed by Ca 

 I.ahire in 1692, the other by Maraldi in 1707, but they only 

 serve for identification of certain stars, and give neither positions 

 nor exact magnitudes. In 1790 Le Mourner published a cata- 



31 Mars, of which IS occur within the limits of M. 

 Wolf's chart ; 15 of these correspond to his observed positions, 

 with a mean error of ±0-4*. in R.A. and ±13" in N.P.D. Le 

 Mourner's Nos. 7, it, and 19 do not correspond within these 

 limits to any existing stars, but there is no reason to 

 displacement, since Lalande assigns positions which nearly agree 

 with M. W,,lf's. 



Prof. Winnecke observed some years since with the Bonn 

 heliometer the principal stars in this cluster, but his results are 

 not yet published. In 1S70 Prof. Asaph Hall published a cata- 

 logue of 151 stars observed at Washington in the years 1S64- 

 1870, the places being in close accordance with those obtained 

 by M. Wolf. 



The Expected Return of the Comet of 1812. — Ex- 

 tensive sweeping ephemerides prepared by MM. Schulhof and 

 Bossert, after a rigorous discussion of the observations in 1812, 

 have been issued by the Observatory at Paris. They find the 

 most probable period 71*7 years, one year longer than was as- 

 signed by Encke, who first proved the impossibility of representing 

 the observations by a parabola. Further, they consider the 

 effect of planetary perturbation since 1812 may bring the comet 



again to perihelion about the middle of the year 1883. But 

 there is an uncertainty in the actual period of revolution in 1812 

 amounting to ±34 years, so that it is desirable to institute at once 

 a systematic search for the comet. The ephemerides in question 

 are for the three months, August — October; with the sun's true 

 longitude as argument (or, more approximately, with the date), 

 twenty-five positions corresponding to different values of the 

 C iinet's true anomaly are found, which indicate the curve in 

 which it should be sought at the time. The data are too exten- 

 sive to be reproduced here, and their utility would be diminished 

 by curtailment. It may be presumed that the ephemei 

 be within reach of any practised observer who contemplates 

 t.i! ing ] art in the search for the comet. In 1812 the distance 

 from the earth at the time of discovery by Tons was 1 Si, and 

 from the sun 1 -30, consequently the theoretical intensity of the 

 light was o"i8. According to Bouvard, it became visible to the 

 naked eye on August 18, with a pretty bright nucleus and a tail 

 of 2°. On September 12 we read : "la queue de la comete est 

 divisee en deux branches paralleles ; sa longueur parait d'environ 



SCIENTIFIC SERIALS 



Journal of the Franklin Institute, August. — On a theory of 

 Rankine relating to the economy of single action of expansion 

 engines, first published in 185 1, by Prof. Trowbridge. — The 

 specific heat of platinum and the use of this metal in the pyro- 

 meter, by Mr. Hoadle. — Bell chimes in Philadelphia and other 

 places, by Mr. Nystrom. — Electric clocks and time-telegraphs, 

 by Mr. Spellier — Feldspar as a source of potash alum, by 

 Mr. Spiller. — On the prevention of fires in theatres, by Mr. 

 Ilexamer. — Report of the special committee on the pollution of 

 the Schuylkill River. 



Journal of the Russian Chemical and Physical Society, vol. 

 xiv. fascicule 6. — On the specific volumes of elements in liquid 

 and solid compounds, by M. Schalfeyeff. The coefficients of 

 diminution of volume of two elements entering into chemical 

 combination gives, according to the author, a measure of the 

 chemical energy of combination and determines the position of 

 the different elements in the natural scheme of Mendeleeff. — On 

 nitric ethers of the lactose, by Dr. Gue. — On the formation and 

 decomposition of the acetanilide, by Prof. Menshutkin, being a 

 new work undertaken in connection with the researches on 

 etherification. — Barometographe by weight, by M. Kraevitch. — 

 On the influence of dilatation 111 the electrical resistance of 

 copper and brass wire, by M. Cllwolson. — Demonstration of the 

 distribution of electricity on the superficy of conductor-, by P. 

 Van-der-Vlieth. — Photo-electric battery, by J. Bor^mann. — On 

 the existence of a pondero-clectro-kinetic part of energy in the 

 electro-magnetic field, by R. Colly. — Necrology of G. C. Br; uer, 

 the aide optician of the Pulkova Observatory, to whom this 

 observatory, as well as the Russian General Staff and Russian 

 travellers generally, are so much indebted for so many beautiful 

 instruments and so many remarkable adaptations of scientific 

 instruments for travelling purposes. 



CONTENTS p A r. B 



The Literature of Botany. By James Britten 417 



1 tin Hook Shelf : — 



Punman's "Talks about Science" 418 



The Eira Arctic Expedition.— Clements R. Markiiam, C.B., 



F.R.S 41S 



Markree Magneti* Dip.— Dr. W. Dobekck 4:S 



The Gesture Speech of Man.— Hyde Clarke 41) 



Orange Cull ure t» Florida. — Major J. Herschel 419 



wlluam stanlbv jbvons 430 



The British Association 421 



Section C — Geology — Opening Address by Robert Elheridge, 



F.R.S., F.G.S., President of the Section 422 



Section D — Biology — Department of Anthrop logy — Address by 

 W. Boyd Dawkins, M.A., F.R.S. , F.G S.. F.S.A., Professor of 

 Geology and Paleontology in the Victoria University, Vice- 

 President of the Section 434 



Section E — Geography — Opening Address by Sir Richard Temple. 



Bart., G.C.S.I.. D.C.L.. F.R.G.S., President of the Section . . 437 

 Section G— Mechanical Science — ( tpeniog Address by John Fowler, 



C.E., F.G.S., President of the Section 441 



Notes 446 



Our Astronomical Column : — 



The Cluster Pratsepe 448 



The Expected Return of the Comet of 1812 1 iS 



Scientific Serials 448 



