92 CARNEGIK INSTITUTION OF WASHINGTON. 



Dr. Newcomb states that the execution of the work has been pos- 

 sible only through the great mathematical ability, expertness in 

 astronomical computation, and general enthusiasm and fidelity of 

 Dr. Frank E. Ross, recently appointed research assistant by the 

 Carnegie Institution. 



W. n. Reed, Princeton Observatory, Princeton, N. J. Grant No. 

 105. For pay of hvo assistants to observe variable stars. (For first 

 report see Year Book No. 2, p. xxii.) $1,000. 



Abstract of Report. — From March i, 1903, to August 31, 1904, 

 17,112 settings have been made with the artificial star photometer 

 attached to the 23-inch refractor of the Halsted Observatory. The 

 observ^ations have been made on 149 nights. The observing list 

 has consisted, first, of those variable stars that have been reported 

 monthl}^ as faint by Prof. E. C. Pickering, director of the Harvard 

 College Observatory ; secondly, of certain stars selected as stand- 

 ards of magnitude that are now being observed by the Eick, Yerkes, 

 and Harvard observatories ; and, thirdly, of a few stars of special 

 interest, such as Z Draconis and the companion of Polaris. 



The present photometer was found inadequate to the study of the 

 unique variations in Z Draconis that were discovered at this observ- 

 atory last year. For that reason a new nickel prism photometer 

 was ordered with a portion of the money granted by the Carnegie 

 Institution for this year. The delay in securing the proper prisms 

 from Germany was such that no observations have as yet been 

 made with the new instrument. The reduction of the observations 

 has been kept up to date and will be ready for publication as soon 

 as a correct value for the scale of the photographically prepared 

 ' ' wedge ' ' has been determined from observations upon the Pleiades. 



Henry N. Russell, Cambridge, England. Grant No. 2. For pho- 

 tographic dcterniinatio7i of the parallaxes of stars. $1,000. 



The object of this work is to obtain by the photographic method 

 determinations of the parallaxes of stars. The working list con- 

 tains 76 stars, in 55 fields. Of these there are 29 stars of large 

 proper motion ; 21 whose parallaxes have been previously deter- 

 mined, but which are in need of revision ; 17 binary stars, belong- 

 ing to 12 systems; and 9 variable stars. Five stars, the parallaxes 

 of which have been previously well determined, are selected as test 

 objects and with a view of obtaining accurate positions for use in 

 future investigations of secular variation of proper motion. Twenty- 



