Observations of a Comet, 61 



Of the Head of the Comet. 



Whfen the comet is viewed with an inferior telescope, or 

 if the magnifying power, with a pretty good one, is either 

 much too low, or much too high, the very bright rays im- 

 mediately contiguous to the nucleus will seem to belong to 

 it, and form what may be called the head. 



Oct. 19. T examined the head of the comet with an indif- 

 ferent telescope, in the manner [ have described, and found 

 it apparently of the size of the planet Jupiter, when it is 

 viewed with the same telescope and magnifying power. 



With a good telescope, I saw in the centre of the head a 

 very small well-defined round point. 



Nov. CO. The head of the comet is now less brilliant than 

 it has been. 



Of the Coma of the Comet. 



The coma is the nebulous appearance surrounding the 

 head. 



Oct. 19. By the field of view of my reflector, f estimate 

 the coma of the comet to be about six minutes in diameter. 



Dec. 6. The extent of the coma, with a mirror of 24 

 inches diameter, is now about 4' 45". 



Of the Tail of the Comet. 

 Oct. 18. 7h. With a night glass, which has a field of view 

 of nearly 5°, I estimated the length of the tail to be 3°-*-; 

 but twilight is still very strong, which may prevent my see- 

 ing the whole of it. 



Nov. 20. The tail of the comet is still of a considerable 

 length, certainly not less than 2f degrees. 



Oct. 26. The tail of the comet is considerably longer on 

 the south-preceding, than on the north-following side. 



Tt is not bifid, as I have seen the comet of 1769 delineated 

 bv a gentleman who had carefully observed it*. 



Oct. 28. 7-feet reflector. The south-preceding side of the 

 tail in all its length, except towards the end, is very well 

 defined ; but the north-following side is every where hazy 



* Dr. Lind of Windsor. 



and 



