250 CARNEGIE INSTITUTION OF WASHINGTON. 



interval; column 3 evaluates the formula +? 0176+ ? 0063 sin R 

 — ?0296 cos R; column 4 is the resulting corrected residual; column 5 

 shows the corrections derived from the formula — ?0028 sin QR— *0084 

 cos 6/2 for R = S2° to 318°, and the formula + ?0078 sin QR-\- »0071 

 cos 6R for 72 = 318° to 278°; column 6 is the residual left after 

 apphcation of the second correction. It indicates a probable error 

 of ± ?0036 sec 5, or, omitting the last residual, =fc ?0027 sec 5; column 

 7 represents the weights employed in the least-square solutions, based 

 on the number of observations contained in each grouping. 



A comparison between the pivot corrections employed in reducing 

 the San Luis observations and the newly determined values shows them 

 to be of the same form, but the curves representing the old values did 

 not reach quite high enough nor dip quite low enough to satisfy the 

 observed maxima and minima. 



STAFF. 



In addition to his regular duties, the Director has been engaged upon 

 various problems in stellar motion. Mr. A. J. Roy has remained in 

 charge of the observations and has supervised the reduction of obser- 

 vations, being especially employed on the zenith distances of the San 

 Luis observations. Mr. W. B. Varnum, besides his duties as observer, 

 has reconciled the reductions of the San Luis right ascensions and has 

 discussed the observed places for outstanding instrumental correc- 

 tions, which resulted in a modification of the pivot correction. He is 

 now prepared to form the final places. Dr. S. Albrecht has divided 

 his time between observing, reducing observations, and continuing his 

 studies on standards of wave-length. Mr. H. Raymond is employed 

 upon a new method of determining the velocity figure of the distribu- 

 tion of stellar motions; he has also been engaged in various phases of 

 the reduction of observations and has read circles. Mr. H. Jenkins 

 continues as circle-reader and in addition is employed upon the compu- 

 tations. Mr. S. B. Grant has undertaken similar duties. Prof. Dr. 

 A. von Flotow joined the staff late in January 1915; he has been aiding 

 the Director in an attempt to determine the hypothetical parallaxes of 

 the large proper-motion stars. In the regular computing division able 

 assistance has been rendered by Mary E. Bingham, Grace I. Buffum, 

 Livia C. Clark, Mabel A. Dyer, AUce M. Fuller, Florence L. Gale, 

 Bertha W. Jones, Isabella Lange, and Frances L. MacNeill. Four 

 piece-work computers have also been employed. 



