272 PROCEEDINGS OF THE AMERICAN ACADEMY 



think the device will be found of especial utility ; as, in the case of 

 cumbrous mountings, the ingenious modification of an equatorial into 

 an orbit-sweeper, suggested by Sir George Airy, does not appear to 

 be convenient in application. If the orbit is somewhat inclined to the 

 equator, it will be found convenient to stop the equatorial clock for a 

 few seconds after a given space in declination has been passed over. 

 A new system of zones is then begun. 



Nautical Almanac Office, "Washington, 

 May 8, 1880. 



