Great Comet of 1843. 415 



Since the 11th, numerous measurements of the place of the nucleus 

 have been taken with the micrometer attached to the Clark telescope be- 

 longing to Yale College ; but these observations have not hitherto been 

 available, for want of full catalogues of the stars. 



On Friday evening, the 17th March, the moon being fairly out of the 

 way, the comet shone with great brilliancy and beauty. The curvature 

 of the train was less than on former occasions. Its length was now only 

 about 34°, the extremity terminating a little beyond the star 60 Eridani. 

 After this date the comet gradually faded, the nucleus advancing in R. A. 

 and diminishing in southern declination, while the extremity of the train 

 scarcely advanced in R. A., although it moved slowly towards the equa- 

 tor. It was last seen here by the naked eye on the evening of April 3, 

 when, in consequence of the advancing light of the moon, it was barely 

 discernible. The nucleus will probably be visible in the telescope for 

 some time to come. 



Numerous observations of the position of the nucleus, were made on 

 and after the 11th, by Mr. S. C. Walker and Prof. E. O. Kendall, with 

 the aid of the excellent instruments at the High School Observatory in 

 Philadelphia. From measurements taken on the 19th and 26th of March, 

 and 2d of April, these gentlemen computed a third set of elements as 

 follows : 



Perihelion passage, Feb. 27.240348 m. t. Phil. 



Longitude of Ascending Node, 1° 16' 21' .4 



ap't. Eqx. Mch. 26. 

 Inclination, . . . . 35 3 40' 51",8 

 Longitude of the Perihelion, 276 3 59' 32' .5 

 Perihelion distance, . . . 0.00818296 

 Motion, retrograde. 

 In the communication announcing his second set of elements published 

 in the United States Gazette, of Philadelphia, March 27, Mr. Walker 

 remarks : — " These elements do not agree with those of any comet on 

 record ; it must therefore be new. They account for the comet's being 

 seen in the day time on the 28th February, and 1st of March. It had 

 just passed its perihelion ; and on the 28th was far enough east of the 

 sun to be seen in the position quoted by the observers at [Waterbury, 

 Ct.] Woodstock, Vt., Portland, Braintree, New Bedford, &c. 



" The great comet of February, 1843, is one of the most remarkable 

 that has ever appeared in the history of the world for its physical pecu- 

 liarities. * * It is not less remarkable in its geometrical relations. 

 Of all the comets on record whose elements have been computed, (about 

 one hundred and forty five in number,) this of February 1S43 approaches 

 nearest the sun except the great comet of 1680, whose perihelion distance 

 according to the accurate computations of Encke was about six hundred 

 thousand miles from the sun's centre. That of the present comet is about 



