Astronomy 599 



The longitude Calais-Washington depended upon the steps 

 Calais- Bangor, Bangor- Cambridge, Cambridge- New York, 

 New York-Washington, and the final result of the campaign 

 gives Greenwich-Washington 5 h. 8 m. 12.39 ^•' c»r, corrected 

 by Wagner, 5 h. 8 m. 1 2.46 s. It appears that the chronometer 

 expeditions by Bond gave the result nearest to the determi- 

 nation by cable. 



A second campaign was made by Mr. Dean in 1866 over 

 the French cable from Brest to Duxbury, Massachusetts, and 

 a third campaign in 1872, which connected the observatories 

 of both Greenwich and Paris with the United States, and 

 therefore incidentally gave the earlier telegraphic difference 

 of longitude between these observatories. The resulting lon- 

 gitude Greenwich-Washington was 5 h. 8 m. 12.09 s., which is 

 the value now adopted (1896). 



The expedition of 1866 was conducted under unfavorable 

 circumstances, and was not entirely satisfactory in all its 

 parts. It was, however, the first attempt of this sort, and the 

 first demonstration that such determinations could be success- 

 fully carried out in the face of new and peculiar difficulties. 

 The expeditions of 1870 and of 1872 followed the path traced 

 out by Doctor Gould and his associates in i866, and the re- 

 sults of the three expeditions taken together are a substantial 

 addition to geodesy and astronomy. 



SURVEYS WEST OF THE ONE HUNDREDTH MERIDIAN 



The geographical and geological surveys of the region of the 

 United States west of the one hundreth meridian, under 

 Major Powell, Doctor Hayden, and Lieutenant Wheeler, re- 

 spectively, were necessarily forced to pay much attention to the 

 determination of geographical positions. In one way or an- 

 other the Smithsonian Institution has forwarded their work 



