.V. / Ti RE 



[November 2, 1905 



a 451171m, and a 4574-79. Tli.' values obtained by previc 

 observers are given below for comparison: — 



Gill (from stars) 455^79 



McClean (from stars) 4552 6 



Lockyer (spaik) 4552'S 



Exnei «nd Haschtk (s[aik).. 4552 75 



4567-90 4574 6S 



45"" 5 ■•■ 4574'5 

 4568-0 4574 -g 



4567-95 ... 45749 



The importance of having the exact wave-lengths "I 

 these lines in stellar radial-velocity determinations is shown 

 by the differences which would be introduced into Prof. 

 Frost's recent work on the Orion stars by the change from 

 Exner and Haschek's values, as given above and previously 

 used by Prof. Frost, to the new wave-length values. 

 They are as follow : — 



Report of the Yerkes Observatory. — Prof. Hale's 

 report of the work performed at the Yerkes Observatory 

 during the year ended June 30, 1904, has just been re- 

 ceived, and shows that, during that period, neither the 

 results obtained nor the private pecuniary support accorded 

 to the institution fell below the average of previous years. 



The Carnegie Institution of Washington has renewed 

 the grant of 4000 dollars made to the observatory- for the 

 previous year, and the money is to be employed in further- 

 ing the investigations of stellar parallaxes, the observations 

 of variable stars, and the reduction of the solar photographs 

 obtained with the spectroheliograph of the Kenwood 

 Observatory during the years 1S92-5. 



The Snow telescope, which was destroved by fire in 

 December, 1002, has been rebuilt from a gift of 10,000 

 dollars made by Miss Snow, and has since been erected 

 at the Mount Wilson Solar Observatory. 



A gift of a further 10,000 dollars from the Carnegie 

 Institution provided for an expedition, for solar research, 

 to Mount Wilson, where an independent observatory has 

 since been erected under the direction of Prof. Hale, who 

 thus severs his more immediate connection with the Yerkes 

 ( Ibservatory. 



The Bruce telescope having an aperture of 10 inches and 

 a focal length of 50 inches has now been completed, and, 

 under the direction of Prof. Barnard, is yielding splendid 

 results. This telescope gives sharp definition over a field 

 about 9 in diameter. 



The 40-inch refractor is used for the Rumford spectro- 

 heliograph, the Bruce spectrograph, and several other 

 attached instruments, and continues to give increased satis- 

 faction. 



After describing the above, Prof. Hale gives a somewhat 

 detailed account of the excellent work performed in each 

 department, and thereby shows what an important place 

 in the astronomical world is filled by the Williams Bay- 

 observers and observatory. 



Observations of Jupiter's Sixth Satellite. — The 

 results of a series of photographic observations of Jupiter's 

 sixth satellite, made at Greenwich with the 30-inch re- 

 flector of the Thompson equatorial during August, 

 September, and October, are published in No. 4051 of the 

 \stronomische Nackrichten, Thirteen photographs were 

 obtained on eight nights, and the time and length of each 

 exposure, and the position angle and distance determined 

 therefrom, are given in the table published. So far as 

 possible, the two latter quantities have been compared 

 with those given by Dr. Ross's ephemeris which appeared 

 in No. 4042 of the [stronomische Nachrichten, and the 

 differences are appended. 



In order to facilitate the measuring process, the over- 



exposed image of Jupiter, on each plate, was reduced with 



ferricyanide of potassium, leaving an easily measurable 



ed image, but the present results are to be con idered 



as only provisional. 



1 mi Spei i-rum of Nova Persei No. 2. — No. 3, vol. lvi., 

 of the Harvard College Observatory Annals contains a 



NO. l8/9, VOL. J $ I 



detailed risumi of the spectroscopic results obtained at 

 the observatory in connection with Nova Persei No. 2. 



Particulars of the photographs obtained are first given, 

 and then each plate is discussed in order, and a descrip- 

 tion of the spectral changes and of the principal lines in 

 the spectrum given. Special remarks are made in refer- 

 ent- to any peculiar appearance or changes in the spec- 

 trum, such as took place when the star was rising to its 

 maximum brightness and subsequently when its magnitude 

 was oscillating. In this connection an interesting com- 

 parison is drawn between the changes which take place 

 in the spectrum of Mira Ceti during the light-variations 

 of that star and those which were observed in tie Nova 

 spectrum. From this comparison it is deduced that both 

 in the case of Nova- and variable stars of long period the 

 hydrogen lines do not become bright until the star has 

 attained a large portion of its light. 



Reduction Tables for Equatorial Observations. — 

 Appendix No. 3 to vol. iv. of the Publications of tin U.S. 

 Naval Observatory contains a series of tables for the re- 

 duction of equatorial observations. 



These tables have been compiled by Mr. C. W. Frederick, 

 who, in the introduction to them, develops the formulae 

 for tie- construction of the tables of differential refraction 

 for micrometer observations made with an equatorial, 

 describes a method of determining the instrumental con- 

 stants, and explains the use of the six tables included in 

 the work. 



The first three tables show the corrections for differential 

 refraction, for the latitude of the Washington Observatory, 

 tee be applied separately according to the method of observ- 

 ation pursued. 



Tables iv., v., and vi. give the instrumental constants 

 of the 26-inch equatorial, of the Naval Observatory, for 

 use under analogous conditions. 



Photographic Star Catalogue. — From a communication 

 made by M. Lcewy to the Paris Academy of Sciences, we 

 learn that the first volume of the " Catalogue photographique 

 du Ciel " has been published by the Bordeaux Observatory, 

 relating to the region dec. +16 to + 18 , which they 

 undertook to observe. This volume contains the rectilinear 

 coordinates of 49,772 stars, and completes the set of four 

 similar publications undertaken by the French observatories 

 (Algiers, Paris, Toulouse, and Bordeaux) as part of the 

 international cooperative scheme (Comptcs rendus, 

 October 9). 



GEOGRAPHY AT THE BRITISH ASSOCIATION. 



T N arranging the programme of work for the South 

 African meeting, the organising committee of Section E 

 tried he secure papers summarising the geographical con- 

 ditions of the "subcontinent," as it is locally called, or 

 1 hose dealing with general geographical problems. The 

 number of papers by South Africans was smaller than 

 might have been expected, the local committee discovering 

 that geography was the subject for which it was most 

 difficult to see tire papers. South Africa is in the position 

 of having many spei ialists interested in geographical 

 aspects of their specialisms, but has as yet no geographers 

 giving all their time and energy to the subject. 



In spite of this, the programme of the section was a 

 full one, and it would have been difficult to dispose of 

 more business than was accomplished. 



It will be most convenient to consider first those papers 

 which deal with Africa. 



-Mr. H. C. Schunke Hollway, vice-president of the 

 section, communicated a paper on the outlines of the 

 physic al tocography f t he Cape Colony. This was illus- 

 trated by a new orographical map specially prepared by 



tin Surveyor-general, Mr. Cornish-Bowden, shov n 



tour lines at 1500, 3000, 4000, 6000, and 8000 feet. Un- 

 fortunately, sufficient data for plotting the 500-feet contour 

 line — one of the most interesting of all — do not exist ; and 

 even the lines shown on this map arc- only approximations. 

 Here, at the outset, the lack of a good topographical 

 map was bewailed, and throughout the wanderings of the 

 members in South Africa this deficiency was felt al every 



