604 PHILOSOPHICAL TRANSACTIONS. [aNNO 1722. 



An Observation of a Solar Eclipse at Greemvich, Nov. 27, 1722, b. m. By 

 Dr. Halley, LL.D. R.S.S. Astron. Regal, and Savilian Prof. Astron. at 

 Oxford. N° 374, p. J 97. Translated from the Latin. 



At ]^ 28"' 58' the eclipse began. 



3 43 25 the end, but rather doubtful. 

 3 43 45 the eclipse certainly ended. 



The same Eclipse observed in Fleet Street, London. By Mr. George Graham, 



F.R.S. N°374, p. 198. 



P. M. 1^ 28"^ 38' beginning. Apparent time. 



2 29 34 by estimation the cuspes parallel to the horizon. 



3 43 22 the end. 



2 14 44 the duration. 

 Quantity eclipsed 5 ^W^^ digits. 



I had very correct observations both of the sun and stars, the 26, 27, and 

 28th, for determining the exact time by my clock. 



For some minutes before the eclipse began, I observed the sun with a 

 telescope of 12 feet, furnished with a micrometer; keeping that part of the 

 limb in the middle of the glass, where I expected the moon first to touch, and 

 in less than 4 seconds of time, from the moment I judged the eclipse began, 

 it was so considerably advanced, that I cannot doubt of having the beginning 

 to less than 3 seconds. I believe the exact time of ending was within the 

 same limit, though the undulation of the limb was then much greater than at 

 the beginning. The parts eclipsed, measured with the micrometer, at the 

 time of the greatest obscuration, were 927 such parts as the sun's vertical 

 diameter contained 1946; which was taken a little before the beginning of 

 the eclipse. 



By this observation the beginning differed not 24^™, and the end not 4- a 

 minute from Dr. Halley's computation, which he sent me the day before. And 

 if his computation, which was made for Greenwich, had been reduced to the 

 meridian of London, the difference would have been still less. 



The same eclipse was observed by Mr. Hawkins at Wakefield, in York- 

 shire, to begin at I*' 21*" p. m. and to end at 3^ 30*" 3'. The sun's diameter 

 was obscured somewhat more than 5 digits. 



