Dec. 5, 1878] 



NATURE 



99 



knowledge of electricians. If, therefore, my article in Nature, 

 at a time when electric currents of great strength are being so 

 widely introduced into practical working, has contributed to 

 make electricians acquainted with this form of galvanometer, I 

 shall not regret the time I have spent in theoretically and experi- 

 mentally investigating this subject. Prof. Pickering alludes in 

 his book to the improper dip motions of the needle as a defect in 

 his form of galvanometer ; I think I have obviated this by 

 pivoting the axis of the needle at both ends. Since conmauni- 

 cating the results obtained with my ^jr/mw^M/a/ instrument, more 

 elaborate instruments have been constructed and found very use- 

 ful in many instances where the ordinary forms of galvanometers 

 would not have answered the purpose. Eugen Obach 



Woolwich, November 19 



Utilisation of the African Elephant 



I have just read some remarks in Nature (vol. xix. p. 54) on 

 the utilisation of the African elephant, which I think are worth con- 

 sidering. Judgingfrom the specimens in the Regent's Park Gardens, 

 which I suppose have not been selected in any way, and are there- 

 fore only average samples of the African species, I should say that 

 the African elephant would prove hardier and capable of more 

 work than the general run of Indian elephants. I was surprised 

 to find that the two African elephants I saw in the Regent's 

 Park were what the mahouts call " Dohara Band," which I would 

 translate "double constitution." I do not think that more than 

 five per cent, of Indian elephants are placed in this class. It 

 is very rare indeed to see an elephant of this class in a Govern- 

 ment Feelkanah, or in the hands of any European, because 

 wealthy natives value them so highly and give such enormous 

 prices for them, that even when caught by a Government keddah 

 officer they are often sold on account of the fancy prices they 

 fetch. The "Dohara Band" elephant will do a wonderful 

 amount of work on a small quantity of food, and stands fatigue 

 and exposure to the sun far better than any other sort. 



To commence elephant-catching operations in Africa, six 

 " koonkies," i e., elephants trained for catching purposes, would 

 be required, and about twenty men from Assam or some other 

 jungle district of Bengal would be sufficient. With this estab- 

 lishment it would be possible to catch and train at least two 

 hundred elephants in the coiu-se of twelve months. 



H. L. Jenkins 



Clanacombe, Kingsbridge, South Devon, November 24 



OUR ASTRONOMICAL COLUMN 



Orbits of Binary Stars.— In a communication to 

 The Observatory^ Dr. Doberck, of Col. Cooper's Observa- 

 tory, Vlarkree Castle, has summarised the results of the 

 investigations on the orbits of the revolving double stars 

 which have occupied him between ihree and four years, 

 and which he has conducted with so much skill and 

 laborious application. In a climate where the skies are ' 

 too irregularly favourable to allow of an astronomer j 

 occupying himself wholly upon observations, it would be 

 difficult to name any more interesting work to which he 

 could devote his leisure, than such a revision of the j 

 elernents of the binary systems. Dr. Doberck's account 

 of his methods in different cases will be of much service i 

 to any one who may engage upon similar researches. He I 

 has found no reason to detract from the value of the early, ' 

 graphical method of Sir John Herschel ; on the contrary, , 

 instances are mentioned where it has been of the greatest j 

 service in tracing out the general form of the orbit, for 

 correction by more refined processes, as in the difficult 

 case of 2 1768 : indeed, Dr. Doberck considers it superior 

 to the second method given by Herschel from its ad- 

 mitting of the weights being approximately taken into 

 account with ease. In a provisional orbit for the close 

 double star 2 3121, the period assigned is thirty-seven 

 years ; at present we know of only two more rapid 

 binaries. Some of [the orbits included in Dr. Doberck's 

 PfP^^, have been made the subject of communications to 

 the Royal Irish Academy, and have been published in 

 the Transactions. 



Lalande's Stars, Nos. 5,499 and 45,400.— Mr. J. E. 

 uore writes suggesting variation in both these objects. 



In examining the question of variability of any of 

 Lalande's stars, Mr. Gore will find it necessary, in the 

 first instance, to have recourse to the original observa- 

 tions as printed in the " Histoire Celeste," there being 

 many errors in the reduced catalogue. Thus, No. 5,499 

 appears through a misprint at p. 246, where the transit 

 at the third wire is given as 2h. 47m. 45'2s., instead of 

 2h. 42m. 45 "25. The star is really No. 788 of Weisse's 

 Bessel. The following star is also thrown out by a 

 similar error in the time of transit, so that Lalande, 5,520, 

 requires a correction of — 5m. in R.A. With regard to 

 No. 45,400, the suspicion of rariability is probably occa- 

 sioned by a misprint in the "Histoire Celeste," since 

 Piazzi, Bessel, and others estimate the magnitude the 

 same as at present. 



The Annular Eclipse of January 22, 1879.— The 

 first of the annular eclipses of the ensuing year, a return 

 of that of January 10, 1861, which was central in Aus- 

 tralia, commences in Uruguay, whence the belt of 

 annular phase traverses the South Atlantic, passing over 

 Tristan d'Acunha, the few inhabitants of which islands 

 may probably be startled by seeing the sun transformed 

 into a narrow luminous ring while he is high in their 

 heavens. The central line crosses the African continent 

 in the direction of Pemba Island, north of Zanzibar, 

 where the annularity will continue nearly three minutes : 

 the middle of the eclipse at 4h. 6m. P.M., local irean 

 time. 



GEOGRAPHICAL NOTES 



The Council of the Royal Geographical Society have 

 determined to commence, on January i, 1879, the monthly 

 issue of a new series of their Proceedings, imdcr the title 

 of The Proceedings of the Royal Geographical Society 

 and Monthly Record of Geography. The latter part of 

 this title will, we believe, fairly indicate the nature of the 

 contents, which will include the papers read at the evening 

 meetings, original articles, geographical notes, obituary 

 notices, proceedings of geographical societies, and brief 

 analytical notes on new books and maps. Each monthly 

 number will be illustrated with one or more maps, and no 

 doubt in this respect endeavours will be made to meet 

 the wants of a public larger than that contained within 

 the ranks of this popular society, which now numbers 

 some 3,400 members. 



In connection with this we regret to announce that 

 this month's number of the Geographical Magazii.e 

 brings the career of that journal to a close. This regret, 

 however, is considerably mitigated by the fact that the new 

 form of the Geographical Society's organ is intended to 

 take the place of the journal which for so many years has 

 been so ably conducted by Mr. C. R. Markham. Mr. 

 Markham deserves great credit for his disinterestedness 

 in continuing to carry on a journal which aimed so 

 successfully to be the organ of scientific geography in 

 this country. The volumes will form a valuable re- 

 cord of the progress of geography for the period over 

 which they extend. In the December number Mr. 

 Markham gives an account of the career of the journal 

 since its first start as Ocean Highways in 1870. "We 

 trust that the new organ will prove a worthy successor 

 of its predecessor, and that while giving due prominence 

 to geographical news, the conductors will aim at bring- 

 ing geography under the guidance of sound scientific 

 principles. 



The Church Missionary Society have recently received 

 from Mr. A. M. Mackay, of their Nyanra Expedition, 

 the journal of his experiences, extending from December 

 31, 1877, to May 16, 1878, in which occur some useful 

 suggestions to African travellers, as well as information of 

 considerable interest to geographers. On April 30 Mr. 

 Mackay reached Uyui, after a hurried and tedious tramp 



