224 



HISTORY OF ASTRONOMY. 



was established at Washington a depot of charts and in- 

 struments for the use of the navy. A small transit in- 

 strument was erected in a small wooden building near the 

 Capitol, and used for the rating of chronometers. This 

 dpot was for several years under the superintendence of 

 Lieutenant (now Captain) Wilkes. When, in 1838, this 

 officer took command of the exploring expedition, he rec- 

 ommended that a series of observations should be made 



NATIONAL OJ3BEBVATORY AT WASHINGTON. 



in this country, during his absence, upon such celestial 

 phenomena as might be available for the better determi- 

 nation of his longitudes, and their reference to some 

 meridian at home. The government sanctioned the rec- 

 ommendation, and the observations were directed to be 

 made at Dorchester by Mr. Bond, and at Washington by 

 Lieutenant Gilliss. This series was continued until the 

 return of the expedition, in 1842. 



