312 Observations of the Appearance of the Comet. 



in every respect. Hence we may see how much safer, in the 

 event, scientific investigation is than vague conjectures. I 

 subjoin the elements of the comet of 166 1, and those now 

 given by Burckhardt : 



COMET 1661. BURCICHARDT. 



Long, of node SSdeg. 30min. 140 deg. 13 min. 



Inclination 32 deg. 35 min. 7-2 deg. 42 min. 



Place of perihelion, 1 isdeij. 38 min. 74 deg. 12 min. 



Perihelion dist 42,600,000 miles. 96,000,000 miles. 



I am, sir, your obedient servant, 



Andrew Ure. 



Glasgow Observatory, Oct. 16. 



Sir, — Tn the Glasgow Courier of October 5, I had the 

 honour of submitting to the public the results of the joint 

 labours of Mr. Cross and myself, for the preceding month, 

 on the comet, at the Glasgow Observatory. In The Star 

 newspaper of October 11, appeared for the first time the 

 elements of the orbit, as determined by the celebrated Burck- 

 hardt, member of the National Institute. 



It is a duty which J owe to the skill and the unwearied 

 exertions of my associate Mr. Cross, to this patriotic esta- 

 blishment, and also to this country, hitherto considered by 

 the French mathematicians and astronomers unequal to the 

 primary solution of this difficult problem, to state the fol- 

 lowing facts : — On Octobers, at eight hours fifteen mi- 

 nutes, by observations made here, with everv precaution to 

 insure the utmost accuracy, the comet had deviated 42 de- 

 grees 18 minutes from the longitude which Burckhardt's 

 elements assign for that instant. On October 14, at two 

 o'clock in the morningi the longitude, as deduced from a 

 most saiisfaclory transit, was 206 degrees 42 minutes. By 

 the French computation it ought to have been 248 degrees 

 1 minute, differing from nature by 41 degrees 19 minutes. 

 By our elements, which have received a partial correction 

 from iny observations since the 5th, the coincidence on 

 the 8th, at the same time, was within 15 minutes, and on 

 the 14th, within 13 minutes. Our computed latitudes on 

 the 13th agree to a minute with observation, while those 

 of Burckhardt differ by 3 degrees or ISO times that quan- 

 tity. 



The examination of both lias been made by the excellent 

 tables of the parabola, constructed bv Delambre, imperial 

 observer at Paris. It is in the longitude of the perihelion 

 that the chief discordance exists between the French ele- 

 ments and ours, and this amounts to about 31 degrees; 



the 



