;78 



NA TURE 



[_Feb. 17, 1887 



The means for the paralhixes thus obtained for the four inde- 

 pendent sets of measures of 6l' and 61- Cygni respectively are 

 as follows : — 



For 61' Cygni, o"'438 ; for 61- Cygni, o"'44i. 



Prof Pritchard explains that this determination is to be re- 

 garded as provisional only, and that the work will be continued 

 to the end of the annual cycle. The method certainly appear> 

 to be a most promising one, and the publication of the full 

 details of the Oxfortl researches will be awaited with interest. 



Observations of Variable St-\rs in 1885. — No. 151 of 

 Gould's Astronomical yoiirnal contains Mr. Edward Sawyer's 

 observations of variable stars made in 1885. The following 

 epochs of maximum brightness were observed : — R Andromeda;, 

 1SS5 Januarv 10 ; R I.eoni-, about 1884 December 24 ; R Leo. 

 Min., 1SS5 June 26 ; R Bootis, 1S85 May 16 ; R Ursoe Majoris, 

 July I ; .S Ursx Majoris, May 7 ; U Herculis, July 8 ; g Her- 

 culis, June 4, August 2 (?), October l6 ; S Coron.c, May 11 ; 

 X Cygni, i885, January 10 ; R Scuti, 1S85 June 17, August lo(?), 

 and November 16 ; Mira Ceti, February 10 ; R Aquarii, Janu- 

 ary 4. /3 Pegasi and a. Cassiopeia appeared constant, and p 

 Persei nearly so, during the observations. R Coronas was well 

 observed, and .showed numerous but slight fluctuations of light. 

 An unusally bright phase, 6'2m., occurred on August 15, fol- 

 lowed by a rather faint minimum, 7'4m,, on October 13. T 

 Monocerotis was well observed : last minimum, April 20, 

 I5h. 26m. Camb. M.T. ; last maximum, April 27, I5h. 55m. 

 U Monocerotis was observed at minimum on .-Vpril i, and at 

 maximum on April 14. W Cygni was observed at maximum 

 on August 20 and December 16, giving a period of 118 ± 

 days, and at minimum on October 30. 



The Alleged Ancient Red Colour of Sirius. — Mr. 

 Lynn, in the current number of the Ois:rva!ory, shows that the 

 evidence for this star having formerly been of a red colour is 

 much less strong than has frequently been supposed. Prof. 

 Schjellerup had pointed out in his notes on his translation of 

 Siifi, that the designation inr6Ki^i)os applied to the star in our 

 editions of Ptolemy was probably an error of transcription for 

 aeipios ; whilst it had been suggested long ago that, for the word 

 " rubr r " which we find used in reference to it by Seneca, we 

 should re.ally read " fulgor." It certainly has always seemedim- 

 probable that a star of such vast dimensions as' Sirius must be 

 should have so entirely changed its colour in less than 2000 

 years. 



Bright Lines in Stellar Spectra.— Mr. O. T. Sherman, 

 in No. 149 of Gould's Astronomical yournal, brings together 

 various observations of the bright lines which have been observed 

 by Vogel or Copeland in the spectra of ,3 Lyra;, 7 Argus, R 

 Geminorum, and some smaller stars, and compares them with 

 Has elberg's observations of the low-temperature spectrum of 

 hydrogen and the high-temperature spectrum of oxygen, and 

 diaws the inference that the stellar bright lines belong to these 

 spectra. The inference seems scarcely warranted, however, for, 

 on the one hand, the lines in the spectrum of hydrogen are so 

 numerous that, wherever the star-lines lay, it would be easy to 

 find lines near them, so that the accord would have to be very 

 close for any such deduction to be safely based upon it ; and, on 

 the other, the observat'ons of the lines in the stellar spectra are 

 less accurate than Mr. Sherman seems to think. The slight 

 differences in the recorded positions of the bright lines as given 

 by different stars are probably indications simply of a roughness 

 in the readings, and the lines are most likely the same in general 

 in the different spectra. The following may be taken as rough 

 mean positions for the bright line-; in these interesting spectra : 

 600 mm., 58 1, 568, 540, 466, together with the F line of hydro- 

 gen, and, in some cases, D., and the third line of hydrogen at 

 434, assuming that the lines are the same in the various spectra 

 of the type. The close correspondence of the bright lines in 

 R Geminorum to those observed by Cornu in Nova Cygni, 1876, 

 indicates that we probably have there the coronal line 1474 K, 

 the principal chromospheric lines, and the typical nebular line at 

 about 500. 



ASTRONOMICAL PHENOMENA FOR THE 



WEEK 18S7 FEBRUARY 20-26 



/TIj'OR the reckoning of time the civil day, commencing at 



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



At Greenwich on February 20 

 Sun rises, 7h. 6m. ; souths, I2h. 13m. S67S. ; sets, I7h. 21m. ; 

 decl. on meridian, 10° 55' S. : Sidereal Time at Sunset, 

 3h. 22m. 

 -Moon (New on February 22) rises, 5h. 52m. ; souths, loh. 25m. ; 

 sets, I5h. 2m. ; decl. on meridian, 17° 6' S. 

 Planet Rises Souths Sets Decl. on meridian 



that of the following morning. 



Jupiter stationary. 



Annular eclipse of the Sun ; visible only in 



parts of South America, Australia, and the 



South Pacific Ocean. 

 Venus in conjunction with and 1° 17' north 



of the Moon. 



is here employed.) 



GEOGRAPHICAL NOTES 

 It would seem that Dr. Oscar Lenz is only to leave Zanzibar 

 this week. The Times Vienna Correspondent is mistaken in 

 thinking that the Royal Geographical Society expects Dr. Lenz 

 to come direct to London. He must, of course, first render his 

 account to the Vienna Society, which sent him out ; but after that, 

 it is hoped, he will come to London and tell his story. It is pos- 

 sible that before leaving Zanzibar he may have an opportunity of 

 giving Mr. Stanley the benefit of his experience. Mr. Joseph 

 Thomson, in a letter to the Times, endeavours to show that Mr. 

 Stanley is taking a toi rosy view of the prospects of his expedi- 

 tion. Mr. Thomson naturally insists on the superiority of the 

 Masai Land route over all others. Certainly Mr. Stanley exag- 

 gerated the difficulties of this route, and we are inclined to believe 

 that, had it been selected, the expedition might have reached 

 Emin Pasha sooner than by the Congo. It should be remembered 

 that, even if all the vessels on the Middle and Upper Congo are 

 available, they could not possibly convey a thousand jieople in 

 one journey — a good authority assures us that there must be at least 

 three journeys ; so that, unless Mr. Stanley starts on his land 

 journey with only one-third of his caravan, instead of 35 days 

 after leaving Stanley Pool it will take 100 days to reach the 

 mouth of the Aruwimi. At the same time we mvist believe that 

 Mr. Stanley knows what he is about, and is not likely to lay 

 himself open to the reproacli of being so far out in his calculations. 

 In the official report, just issued, on the administration of 

 Lower Burmah during 1885-86, and Upper Burmah during 

 1 886, there are some interesting passages relating to the re- 

 sources of the new British province. .Agricultural products, 

 such as rice, wheat, maize, and other cereals, are grown in large 

 quantities. The country is believed to be rich in mineral re- 

 sources, and the subject is at present under the examination of 

 the Geological Survey. Meanwhile it is known that the country 

 to the north-east of iWandalay is the richest, if not the only, ruby- 



