XVlll CARNEGIE INSTITUTION 



Astronomy. 



Lewis Boss, Dudley Observatory, Albany, N. Y. Grant No. 7. 

 For astronomical observatiotis and compntations. $5,000. 



Abstract of Report. — This work has for its ultimate object an inves- 

 tigation upon the motions of the brighter stars (all down to the 

 seventh magnitude), and of all stars, of whatever magnitude, sup- 

 posed to have motions as great as 10" per century, and^of many 

 other stars which were specialh- well determined prior to 1850. 



During the year Professor Boss's attention was given to — 



(a) The compilation for each star of all observations for position 

 that have been made upon it during the history of astronomy. Some 

 stars are found in more than sixty catalogues. 



(J)) Investigation of the systematic errors with which each series 

 of meridian observ^atious seems to be affected, in order that the pre- 

 cision of the results ma}- be notablj- increased. This involves in 

 the first place the establishment of a standard of reference, which 

 must include the positions of all those stars w^hich have been most 

 frequently and accurately observed. 



The entire work is proceeding upon a logical plan carefully studied 

 and formulated through the results of experience during past years, 

 with a view to economy in the succession of individual investigations 

 designed to contribute to the final result. In an extensive investi- 

 gation of this kind there is always an element of danger. If the 

 work is so planned that definite results cannot be realized until 

 the completion of the whole work, there is liability to serious loss 

 from the ordinary accidents of life which cannot be foreseen. There- 

 fore this work has been so planned that useful results can be secured 

 and promptly published at every successive stage of the work. Each 

 step grows logically out of those which have preceded it. The 

 computations are so planned that successive improvements in the 

 fundamental basis can be introduced with the least possible duplica- 

 tion of work. 



It is intended that the catalogue of more than 2,500 standard stars 

 shall be offered for publication to the Carnegie Institution early in 

 1905, and if no unforeseen accidents occur this program should be 

 entirely feasible. 



During the present year the catalogue of 627 standard stars has 

 been passing through the press and is now nearly ready for issue. 

 Subsidiary investigations connected with this catalogue have been 

 carried out under the grant of the Institution for this year. 



