220 CARNEGIE INSTITUTION OF WASHINGTON. 



STAFF. 



The Director, in addition to his general duties, has devoted much 

 time to the study of sun-spot hypotheses and other solar problems. 

 Dr. Walter S. Adams, Assistant Director, has continued his investi- 

 gations in stellar spectroscopy. Professor Frederick H. Seares, super- 

 intendent of the Computing Division and editor of the Observatory 

 publications, has carried forward his stellar researches and his work 

 on the general magnetic field of the sun. Dr. Arthur S. King, superin- 

 tendent of the Physical Laboratory, has devoted most of his time to 

 investigations with the electric furnace. Dr. Charles E. St. John has 

 continued his studies of the solar rotation and the wave-lengths of lines 

 in the spectra of Venus and the sun. Dr. J. A. Anderson has applied 

 the Michelson interferometer to the measurement of Capella, studied 

 the spectra of explosive electric discharges, and continued his tests of 

 the ruling-machine with Mr. Jacomini. Dr. Harlow Shapley has 

 pushed forward his investigations of star-clusters, variable stars, and 

 other sidereal problems. Professor G. W. Ritchey gave up his con- 

 nection with the Observatory in October. Mr. Harold D. Babcock 

 has given his chief attention to his investigations of solar and standard 

 wave-lengths. Mr. Francis G. Pease has carried on his work of in- 

 strumental design and his photographic observations of the moon and 

 nebulae, and has assisted Professor Michelson in his tests of the inter- 

 ferometer and the velocity-of-light apparatus. Dr. Paul W. Merrill 

 studied the spectra of the long-period variable stars and spent part of 

 his time in laboratory work. Mr. Ferdinand EUerman has taken part 

 in the solar observations and served as Observatory photographer. 

 Dr. Adriaan van Maanen has devoted most of his time to the determin- 

 ation of trigonometric parallaxes and proper motions, and has made 

 additional measures of the general magnetic field of the sun. Professor 

 Alfred H. Joy, recently appointed secretary of the Observatory, has 

 been engaged chiefly in stellar spectroscopic investigations. Dr. 

 John C. Duncan, who joined the staff in June, has made photographic 

 observations of nebulse and taken part in the stellar spectroscopic work. 

 Dr. Seth B. Nicholson has continued his observations of the sun and 

 Venus, and his calculations of the orbit of the Ninth Satellite of Jupiter. 

 Dr. Gustav Stromberg has continued his work on absolute magnitudes 

 and spectroscopic parallaxes. Dr. R. F. Sanf ord has spent most of his 

 time in stellar spectroscopic investigations. Mr. Edwin P. Hubble, 

 who joined the staff in September, has devoted his entire attention to 

 investigations of nebulse. Mr. Frederick S. Brackett, who resigned 

 from the staff on August 31 to continue his studies at Johns Hopkins 

 University, has engaged in solar spectroscopic work. Mr. W. P. Hoge, 

 night assistant with the 60-inch telescope, has taken part in the stellar 

 spectroscopic observations. Mr. Milton Humason, night assistant. 



