Dec. 20, 1883] 



NA TURE 



^85 



sufficient in Western Transcausia, vvhibt in the eastern parts of 

 the country irriu;ation would be necessary. 



L'Aslroiiomie states in its last number, in reference to a recent 

 note in Nature, that Admiral Mouchez has drawn up a 

 memorial praying for the removal of the Paris Observatory from 

 its present position, but that he has not yet presented it to the 

 Council of the Observatory, but will do so at an early period. 

 It is not the first time that the idea has been started. The 

 proposal was made in 1S6S, and a Commission appointed to 

 report on the matter. The scheme was objected to strongly by 

 Leverrier, and finally rejected after a very sharp discussion. 



The Swedish frigate VatiaJis has just started on a cruise 

 round the world. King Oscar's second son participates in the 

 cruise, as well as Dr. Hjalman Stolpe, who has Leen commissioned 

 by the Government to collect materials for the nucleus of a 

 National Kthnographical Museum in Stockholm. The frigate, 

 whose mi.-sion is chiefly scientific, will call at many places of 

 interest, as, for instance, the Straits of Magellan, the Marque,-as 

 and Sand « ich Islands, the remarkable Maiden Island, &c. A 

 Swedish merchant, M. Fiirstenberg of Gothenburg, has cantri- 

 buted 600/. for the purchase of objects of scientific value. 



M. BoURDALOU, having published in 1864, in his work^ 

 " Nivellemer.t General de la France," that the average level of 

 the Mediterranean is by 072 metres Ijwer than that of the 

 Atlantic, this result was received with some distrust by 

 geodesists. General Tillo points out now, in the last issue of 

 the Russian Izveslia, that this conclusion is fully tupported by 

 the results of the most accurate levellings made in Germany, 

 Austria, Switzerland, and Spain, which have been published 

 this year. It appears from a careful coiiipari-on of the mareo- 

 graphs at .Santander and Alicante by General Ibanez, that the 

 difference of levels at these two places reaches 066 metre, and 

 the differences of level at Marseilles and Amsterdam appear to 

 be O'So metre when compared through Alsace and Switzerland; 

 the Comptcs Rendtis de la Commission PermanenU del' Association 

 Giodisiqiie Internationale arrive at 0757 metre from the com- 

 parison with the Prussian levellings, whilst the fifth volume of 

 the " Nivellements der Trigonometrischen Abtheilung der 

 Landesaufnahme " gives o'Sop via Alsace, and 0'832 via Switzer- 

 land. The diilerenee of levels at Trieste "and Amsterdam, 

 measured z-id SiUsii and Bavaria, appears to be 0*59 metre. 

 Each of these four results (072, o'66, o'8o, and o'59), having a 

 probable error of o" I metre, their accordance is quite satisfac- 

 tory, and we may admit thus that the average level of the 

 Mediterranean is in fact lower by 07 metre than that of the 

 Atlantic. 



The additions to the Zoological Society's Gardens during the 

 past week include a Macaque Monkey (Macacus cynomolgus i ) 

 from India, presented by Mr. J. L. Waldon ; a Night Heron 

 (Nyclicoiax griseus), European, presented by Mr. N. H. Fenner ; 

 two Barbary Turtle Doves ( Turtur risontis) from North Africa, 

 presented by Miss Stewart ; four Ring-hals Snakes {Sepedon 

 hamachetes], a Hoary .Snake {Coronella cana) from South Africa, 

 presented by the Rev. G. H. R. Fi,k, C.M.Z.S.; a Black-faced 

 Kangaroo (Maciopiis jnelanops i) frjm Australia, a Broad- nosed 

 Lemur (I/apaLmiiy siiniis i ) from Madagascar, an Exanthe- 

 matic Monitor { Varanii. e.xanthematicus) from West Africa, 

 purchased. 



OUR ASTRONOMICAL COLUMN 

 The Mass of Saturn. — Prof. Aja;.h HjU has communi- 

 cated to the Royal Astronomical Society a note upon the mass 

 of Saturn deduced from observations of the outer satellite 

 Jafetus, made with the 26-inch refractor at the Naval Observa- 

 tory, Washington, in 1S75, 1S76, and 1S77. The mean distance 

 of the satellite from its primary, reduced to the mean distance of 

 the latter (9'53885), was found to be 5i5"-522 from 128 obser- 

 vations. For the periodic ti.ne of Japeuis Prof Hall compaied 



his ortn observatioi.s with one by Sir W. Herschel on Sept. 20, 

 1789, and with Sir John Herschel's observations made at the 

 Cape of Gojd Hope in 1837. The resulting sidereal revolution 

 's 79'33ioi52 days. Hence the mass of Saturn iu units of the 



sun's mass is Bes!-el, from heliometr.c measures of the 



3482-2 



great satellite Titan obtained a value of - — , which has been 



3501-6 

 siuce used in nearly all calculations where the mass of this planet 

 enters ; Jacob, from obtervations of Tttan made at Mad'as in 



if , which it will te seen closely 



3487-2 

 approaches that given by Prof. Hall. The value deduced by 



- , and therefore is 

 3529'S6 



[856-58, i.if erred a mass 



ipproaches that given b 

 Leverrier fi-om the theory of Uranus is 

 the smallest of all. 



Close Double-Stars. — M. Perrotin has published in the 

 Astroiwiiilsche Nachricliten further mea ures of double-stars made 

 at the Observatory of Montgros, Nice, amongst which are some 

 of the close binaries. In July last he thought 72 Ophiuchi 

 (rather a problematical object) might be elongated in the direc- 

 tion no", bat in the following month it appeared single under 

 good conditions of atmosphere. Of the closer stars we find — 



Positiun Distance 



7) Corontc Boreal. s ... 1883-564 ... 156-00 ... 0-610 



2 193S -595 --• II2'95 -•■ 0750 



f hquulei -640 ... 285-57 -- o'973 



0.2. 395 '667 ... 95-30 ... 0-690 



Po»Ns' CoMEi'. — -The following approximate places of Pons' 



comet are deduced from the provisionally corrected elements of 



MM. Schulhjf and Bossert : — 



At Cranwich Midnight 



,R.j _, R-A. Decl. Log. distance from 



■' ■* h. in. s. . , Earth Sun 



Dec. 31 ... 21 39 4 ... -h23 54-9 ... 98263 ... 9-9585 



Jan. 2 ... 21 53 26 ... 20 45-2 



4 --• 22 7 37 ... 17 22-8 ... 9-S09S ... 9-9409 



o ... 22 21 31 ... 13 49-5 



8 .. 22 35 3 ... 10 7-5 ... 9-8029 ... 9-9249 



10 ... 22 48 9 ... 621-0 



12 ... 23 o 44 ... -I- 2 33-2 ... 9-S065 ... 9-9111 



14 ... 23 12 45 ... - I 12-2 



16 ... 23 24 10 ... 4 52-7 ... 9 8201 ... 9-9002 



iS ... 23 34 58 ... 8 249 



20 ... 23 45 8 ... II 47-7 ... 9-8414 ... 9-8928 



22 ... 23 54 41 ... 14 59 s 



24 •■- o 3 37 --• 17 59'9 ■-- 9'8678 --- 9'8894 



26 ... on 57 ... 20 48 2 



28 ... o 19 44 ... -23 25-1 ... 9-8966 ... 9-S901 



The intensity of light is at a maximum in the middle of 

 January. The comet will be nearest to the earth on January 9, 

 dis.ance 0-634, or rather less than two-thirds of the e.irth's 

 mean distance from the sun. At its last appearance in 1812 it 

 did not approach the earth within about 1-35. 



Tempel's Comet, 1867 II.— M. Raoul Gautier of Geneva 

 is engaged upon a revision of the orbit of this comet, which, it 

 may be remembered, experienced great perturbations from a 

 near approach to the planet Jupiter during the revolution 1867- 

 73- It may probably arrive at perihelion again about May, 

 1885. If there should still be unpublished observations of this 

 comet, it would be desirable to communicate them at once to 

 M. Gaiitier, that they may be brought to bear upon his investi- 

 gation. 



De Morgan's Five Figure LoGARiTHMS.^There is a report 

 that the five-figure tables of logarithms of numbers and trigono- 

 metrical functions published "under the superintendence of the 

 Society for the Diffusion of U.seful Knowledge," but which are 

 usually known as De Morgan's Table-, are out of print, and 

 that there is no present intention of a further issue. If this be 

 the fact, it is much to be regretted : they are by far the most 

 convenient five-figure tables that we posses-, on the score of size 

 and legibility, and have been widely utiliied in astronomical 

 calculations. Lalande's Tables, the stereotype edition of Firmin 

 Didot, are good, and the same may be said of Gauss's, where it 

 is of advantage t.) have two degrees on one opening ; but we 

 neverthele.-s unhesitatingly give the preference to "De Morgan." 



