]Q2 SCIENTIFIC RECORD FOR 1884. 



Schoeufeld's D. M. is published. Certain further conclusions may also |: 



be drawn from the author's figures. This paper is the most impor- f i 

 taut which has appeared on this very interesting question since the pub- 

 lication of Dr. Gould's TJranometria Argentina. 



ASTRONOMICAL CONSTANTS. 



New investigations on the constants of precession.— In one of the last 

 meetings of the " Niederrheiuische Gesellschaft flir Natur und Hed- 

 kunde," Dr. Schoenfeld presented a lately published article by Dr. F. 

 Bolte 'entitled " Investigations on the Constants of Precession, based 

 upon 'the Star catalogues of Lalande and Schjellerup." The writer 

 here makes the first attempt to take into consideration the systematic 

 proper motion of the fixed stars in the determination of these important 

 constants ; while up to this time those parallactic changes of star posi- 

 tions, at most, have been considered which are due to the motion of the 

 solar' svstem. Such systematic proper motions may be of different 

 kinds but the most obvious assumption is that they occur in planes 

 which are but slightly inclined to the plane of the Milky Way. This is 

 the idea that the writer has adopted, and he has applied it to the 3,300 

 stars common to the above mentioned catalogues, supplementing a 

 treatise of Dreyer's, in which the latter discusses the R. A.'s of these 

 stars by considering their declinations at the same time. The result 

 for the precession is a very good substantiation of Struve's constant, 

 now so commonly used in our almanacs; as to the assumed common 

 motion of the stars however, the result is an entirely negative one, for 

 its value, determined as 0".4 per century, is much less than its probable 



error. 



The speaker touched upon various possible explanations of this in- 

 teresting result, particularly this : That the attraction of the Milky 

 Way upon the individual stars may be counteracted by the attraction 

 of the nebuhi3 which arc mostly thickly clustered about the poles of the 

 Milky Way.— From Sirius, February, 1884. 



CATALOGUES OF STARS. 



Progress ofthczone-ohservations of stars 1-9 mag. of the German Astro- 

 nomical Society.-Easan : Zone 80O-75o. The printing is begun and it 

 gives the star places reduced to the beginning of the year. The reduc- 

 tion to 1875 is still to be made. 



Dorpat: Zone 75O-70o ; and Christiania : Zone 70O-65o. The work 



for these zones is nearly completed. 



Eelsingfors-Gotha: Zone 650-55°. The printing is well advanced. 



Cambridge (U. S.) : 550-50°. The printing has begun ; the work ol 

 reduction to 1875.0 is about half done. A certain number of stars re^ 

 quire reobservation. The probable errors of a position are about 0^08 

 and 0".8. 



