HIS ASTRONOMICAL WORK 45 



This new building was to be of brick, in the form of a 

 square about 50 feet by 50, surmounted by a dome 23 

 feet in diameter, with wings to the south, east, and west. 

 Later, in 1847, the superintendent's residence was con- 

 structed and connected with the main building by an ex- 

 tension of the east wing. 



The name of the institution varied. As the Depot of 

 Charts and Instruments it was officially known from 

 1830 to 1844; but for the next ten years the names Naval 

 Observatory and National Observatory were used in- 

 discriminately, sometimes even in the same publication. 

 In December, 1854, the Secretary of the Navy instructed 

 that it should henceforth be called the United States 

 Naval Observatory and Hydrographical Office, and as 

 such it was known until the establishment of the Hydro- 

 graphic Office as a separate division in 1866. Since that 

 date the official name of the institution has been the 

 United States Naval Observatory. 



Near the close of September, 1844, the Observatory was 

 reported to be completed, and on October 1 Maury was 

 ordered to take charge with a staff of line officers and 

 professors of mathematics of the navy, and civilian pro- 

 fessors. Lieutenant James M. Gilliss, Maury's prede- 

 cessor, had been greatly interested in astronomy, espe- 

 cially that field of the science having to do with 

 navigation, and it was largely through his exertions that 

 the necessary legislation had been passed making possible 

 a building, adapted not merely to the housing of charts 

 and instruments but suitable as well for astronomical 

 observations. He had been sent to Europe to consult 

 about the purchasing of instruments for the new Observ- 

 atory, and there were those who thought that he should 

 have been made its first superintendent. 



