Astronomy. 377 



10th till the 18th October. On the 11th, the tail was very narrow at its 

 setting out from the nucleus, and grew less to a certain distance, when it 

 widened in the form of a fan. On the 12th, its body was more rough, and 

 the tail a little curved, being very narrow at its origin, and wide at its 

 termination. On the 13th its tail was very shapeless, being considerably 

 bent towards the middle, and as it were in detached pieces. On the 14th, 

 it had a more uniform aspect- On the 15th, the tail was divided into two 

 very sensibly. On the 16th, the tail was very small and faint, and con- 

 sisted of two parts, one of which was more distinct than the other ; and 

 on the 17th, the tail was a little curved. 



M. Capocci has also remarked, that the long tail of this comet is subject 

 to continual and very perceptible changes in a short space of time. He 

 believed that he had almost seen the undulations which Pingre had re- 

 marked in the comet of 1779. On the night of the 7th or 8th of October, 

 the tail was divided into three branches, the chief of which was interrupt- 

 ed by a considerable space almost void of light, after which the nebulo- 

 sity reappeared, which extended itself to a great distance, bending itself 

 on the side opposite to the path of the comet. 



4. Hansen's elliptical elements of the second Comet of 1825. Having 

 perceived that the parabolic elements of this comet, which he calculated, 

 and which we have given above, differed more than three minutes from ob- 

 servation, M. Hansen computed the following elliptical elements, which 

 agree very accurately with the observations made at Seeberg, Florence, 

 Turin, Naple, and Vienna. 



Zach's Cor. Astron. vol. xiii. p. 495. 



5. F if tit. Comet of 1825. The following are the elements of this comet 

 calculated by M. Capocci: 



Passage of Perihelion, . 1825, Sept. lC d 4866 si. T. Naples. 



Perihelion distance, . . 3.1971 



Long, of Perihelion, . . 46° 34' 15" 



Long, of node, - . . . 211 58 50 



Inclination of Orbit, . . . 60 5 35 



Motion Direct. 



6. Mr Pond's Observations on the Double Star ? Boot is. The following 

 account of this interesting double star was sent by Mr Pond to Mr South. 

 " I first observed ^Bootis to be a close double star at Lisbon in the year 179,5, 

 with a seven feet reflector, which the late Sir W. Ilcrschcl made for mc ex- 



