34-6* ASTRONOMICAL OBSERVATIONS 



Don Joseph de Cotilla, situated in latitude 22° 55' 1(5" N. 

 and 44", 3, in time, E. of Havanna. 



The times of the observations were determined by a good 

 chronometer, regulated by absolute and corresponding altitudes 

 of the sun and stars, and the times observed at ihe plantation, 

 are referred to the city of Havanna, by the difference of meri- 

 dians. 



To determine the place of the comet, many series of obser- 

 vations were made with two or three of the above named stars, 

 choosing those that made the most convenient triangles, and as 

 the different observations could not be made at the same time, 

 care has been taken, to refer all the distances observed, to the 

 same instant, by means of the variation observed of the dis- 

 tances of the said stars from the comet. 



The distances observed were freed from the effects of refrac- 

 tion, corrected by reference to the state of the thermometer 

 and barometer. 



The places of the stars were taken from the Connoisance dc 

 temps, of Paris, 1806; allowance being made for the proper 

 motion, precession of the equinox, nutation and aberration. 

 Further, the latitudes and longitudes of the said table are the 

 apparent, that is, affected by the nutation and aberration. The 

 elements of the orbit of the comet were calculated from the 

 first observations which I made in Havanna, that is, from 1st 

 Octr. to 7th Novr., by Don Francis Leamur, Lieutenant Col. 

 of the Royal Corps of Engineers, and are the following : — 



Passage through the perihelion, mean time at the city of Havanna, Septr. 18th ll 1 ' 58' 59'< 

 Longitude of the ascending node. ... 8 s 26° 39' 09" 



Inclination of the orbit 63 12 30 



Place of the perihelion 9 00 45 01 



Perihelion distance, that of the sun being 1. . . 0,6462128 



After having concluded the observations, namely up to the 

 1st December, I determined to calculate the elements of the 

 parabolic orbit, by the combination of all the observations, and 

 the following elements are the results. 



Passage through the perihelion, mean time, at the city of Havanna, Septr. 18. 12 h 37' 00'' 



at Greenwich, . . . 18 06 40 



Longitude of the ascending node from the mean equinox=«=8 s 26° 42' 12" 

 Inclination of the orbit. . . • . 63 12 51 



Place of the perihelion. . . . . . . 9 00 51 35 



Perihelion distance, that of the sun being 1 0,6462667 



