I 



y^tne 2, 1887] 



NATURE 



ii3 



Astronomical PHOTOGRArHV. — T.:c Nciv Princc'on Re- 

 "view for May 1887 contains an interesting article, by Prof. C. A. 

 Young, with the above title. The article is, of course, of quite a 

 popular character, but none the less is it deserving; of perusal by 

 astronomers — professional as well as amateur. In a rapid survey 

 of the history of astronomical photography. Prof. Young refers 

 briefly to the labours of J. W. Draper, Bond, Rutherfurd, 

 Gould, Henry Draper, and Pickering, in America ; of De la 

 Rue, Common, and Roberts, in England ; of the Brothers 

 Henry, in P" ranee ; of Vogel, in Germany ; and of Gill, in South 

 Africa. He then goes on to discuss the relative advantages and 

 '{disavantages attending the employment of the reflector and of 

 the refractor respectively in this particular department of agro- 

 nomical science ; pointing out, in the case of the refractor, the 

 two directions in which, at the present time, efforts are being 

 made to overcome the difficulties a'ising from the want of per- 

 fect achromatism of the object-glass, viz. Prof. Abbe's re- 

 searches on the production of glass which shall be perfectly 

 achromatic, and Herr Vogel's investigations on a new sensitizing 

 medium which may be as sensitive to the yellow and green rays 

 as the salts of silver are to the violet rays. In the remaining 

 portion of the article Prof. Young distinguishes two classes of 

 astronomical photographs : those in which the end is to produce a 

 \picture of the object ; and those which are made for purposes of 

 \meaiurement, and the determination of precise numeric il data. 

 He gives various examples of each class, with a brief account of 

 the progress which has been made in solar, lunar, planetary, 

 [stellar, and nebular photography, as thus classified, concluding 

 iwith an account of the very remarkable results which have 

 recently been obtained by Prof. Pickering in the photography of 

 stellar spectra. 



Comet 1887 e (Barnard, May 12). — Dr. H. Oppenheim 

 {Astron. Nachr. No. 278) has computed the following elements 

 and ephemeris of this comet from an observation made at 

 Cambridge, U.S., on May 12, and from two others made at 

 Rome on the 15th and 17th : — 



T = 1887 June 24-5559 Berlin M.T. 



7r - a = 24 2/ 30 1 



Q, — 244 54 32 > Mean Eq. i887"o. 

 . = 17 9 21 ) 

 log q — 011510 



Ephemeris for Berlin Midnight. 

 1887. R.A. Decl. > Log A. Log r. Bright- 



h. m. s. o ( ness. 



June I 154955 1612-35. 9*5323 0-1299 2-0 



5 16 o 2 12 19-1 95185 0-1253 2-2 



9 16 10 46 8 17-1 9-5097 0-1216 2-3 



13 16 22 I 4 13-9 95062 0-1186 24 

 The brightness on May 12 is taken as unity. 



ASTRONOMICAL PHENO\fKNA FOR THE 



WEEK 1887 JUNE 5-1 1. 



( pOR the reckoning of time the civil day, commencing at 



^ Greenwich mean midnight, counting the hours on to 24, 



is here employed.) 



At Greenwich on June 5. 

 Sunrises, 3h. 48m. ; souths, iih. 58m. io-2s. ; sets, 2oh. 8m. ; 

 decl. on meridian, 22° 33' N. : Sidereal Time at Sunset, 

 I3h. 4m. 

 Mjon (Full on June 5) rises, I9h. 31m.; souths, oh. 4m.*; 

 sets, 4h. 32m.* ; decl. on meridian, 18" 7' S. 

 Planet. Rise<:. Souths. Sets. Decl. on meridian, 



h. m. h. m. h. m. ^ , 



Mercury ... 4 15 ... 12 44 ... 21 13 ... 25 6 N. 



Venus 6 47 ... 15 i ... 23 15 ... 23 8 N. 



Mars 3 14 ... II 15 ... 19 16 ... 21 13 N. 



Jupiter 15 26 ... 20 44 ... 2 2* ... 8 56 S. 



Saturn 6 29 ... 14 35 ... 22 41 ... 21 56 N. 



• Indicates that tUe southing and setting are those of the following morning. 



Variable Stars. 

 Star. R.A. Decl. 



h. m. , , h. m 



U Cephei o 523 ... 81 16 N. ... June 8, i 16 m 



5 Librae 14 54-9... 8 4S 11, i 52 m 



U Coronse 15 13-6 ... 32 4N , 7, 23 48 m 



W Scorpii 16 5'2 ... 19 51 S. ... ,, 7, AI 



U Ophiuchi 17 io"8 ... i 20 N. ... ,, 10, o 14 w 



M signifies maximum ; in minimum. 



Occultations of Stars by the Moon (visible at Greenwich) 

 June. Star. Mag. Disap. Reap 



h. m. 

 20 52 

 20 40 

 23 49 



Corresponding 

 angles from ver- 

 tex to right for 

 inverted image, 

 h. m. 00 



21 59 ... 60 224 

 21 39 ... 20 258 



o 53t ... 42 275 



5 ... 29 Ophiuchi ... 6 



6 ... B.A.C. 6081 ... 6 

 10 ... 45 Capricorni ... 6 

 10 ... 44 Capricorni ... 6 ... 23 58 near approach 156 



t Occurs on the following morning. 

 Saturn, June 5. — Outer major axis of outer ring = 38"*i ; 

 outer minor axis of outer ring = 15" -2 ; southern surface visible. 



Meteor- Showers. 



R.A. Decl. 



Near Antares ... 

 /8 Ophiuchi 



249 

 261 



20 S. 

 5 N. Rather slow. 



GEOGRAPHICAL NOTES. 



The Expedition which went out to explore the New Siberiaa 

 Islands, has returned to St. Petersburg with interesting results. 

 The Expedition was organized by the Academy of Science, St. 

 Petersburg, 26,000 roubles being contributed by the Emperor 

 Alexander. Operations commenced in 1885, and considerable 

 preparations had to be made. A winter retreat was chosen ia the 

 district of Kasachje (under 71° N. lat.), 30 kilometres sjuth 

 of Ustjansk at the mouth of the Jana. About 270 kilometres 

 distant from Kasachje, were discovered the remains of a mam- 

 moth. At the end of March 1886, Dr. Bunge left for the 

 Swatoinoss Mountains, where the real march with 240 dogs was to 

 begin; 19 sledges drawn by 12 dogs, led the expedition over 

 the frozen sea. In the latter half of April, the Jakutes returned 

 with the sledges, and reported that the journey had been success- 

 fully accomplished. Dr. Bunge devoted his attention in parti- 

 cular to the Liachow Island, while Baron Toll attempted not 

 only Kotelni Island, but also the Island of New Siberia. In May 

 both explorers were at the Medwesh^i foothills, to the south of 

 Kotelni Island. Liachovv Island has a very uniform but rough 

 appearancj ; it is 300 kilometres in circumference, the surface 

 bein.j uneven and hilly. The prevailing winds are east and west. 

 The latter is extraordinarily violent, and works great mischief ;. 

 it brings first rain, and then frost. Winter retires about the 

 beginning of June, although the summer is never quite free from 

 snow, mist, storms, &c. Enormous masses of perpetual ice 

 inclose the island ; only once could Dr. Bunge make a sea 

 passage free from ice. In clear weather, looking northwards 

 from Kotelni Island land is visible, which appears to be only 

 150 kilometres distant. The possibility of reaching this land is 

 increased by the fact that a warm current flowing in a fixed 

 direction prevents the sea from freezing over. The highest 

 observed temperature in Liachow Island was ouly 8' (Reaumur). 

 The snow melted in the beginning of June, and about the middle 

 of tho same month the first flower was found. Wild reindeer, 

 wolve.-;, Arctic foxes, and mice are found on these islands, as also 

 sea-gulls, snipe, and other birds. With the exception of the mouse, 

 all animals on the island are merely guests ; they all winter 

 on the Ian 1. 



The Canadian Government sent out at the beginning of May 

 an Expedition for the exploration of the region watered by the 

 great river Yukon in the north-west of the Dominion. The 

 geology and natural history of the Expedition will be under the 

 care of Dr. Dawson of the Canadian Survey ; while a careful 

 topographical survey will be made by Mr. W. Ogilvy. 



In the new number (128) of the Zeitschrift of the Berlin Geo- 

 graphical Society, Prof. Blumentritt has some critical remarks on 

 the Spanish data with reference to the distribution of the native 

 languages in the Philippines. Colonel Schelling contributes a 

 useful abstract of the Russian Survey work up to 1885, and Dr. 

 Emil Deckert a paper on the country and people of the Southern 

 United States. 



The German Government has appointed Lieut. Kund, who- 

 has done such good work in the Congo region, chief of the 

 scientific station which has been established at the Cameroons ; 

 for when the Germans undertake the development of any regioa 

 they at once recognize the nece sity for scientific observations in 

 order to accomplish their object. A surgeon and botanist will 



