286 RESULTS OF OBSERVATIONS OF COMETS I. AND II. 



telegraphed from the Cape of Good Hope on the date of discovery 

 was unfortunately affected with some error, which rendered it 

 useless as a basis for calculation. The Windsor position for 

 February 27th, resting as it did on seventeen excellent comparisons 

 with well-determined stars, was adopted by Herr Berberich in 

 conjunction with observations at Palermo on March 13th, Rome 

 on March 24th, Kiel on April 5th, and Kiel and Hamburg on 

 April 12th. The comet did not become visible to the Southern 

 •Observatories of Europe till about the 13th March. The following 

 are the elliptic elements arrived at by Herr Berberich : — 

 T= 1888, March 17, -03844, Berlin M. Time. 



o / // 



co = 359 m 20-3) 



Si =245 23 25-8 } Mean Equinox, 1888-0. 



i = 42 15 19-8 ) 



Log. e = 9-998290. 



Log. ? = 9-844346. 

 These elements represent the first and last positions exactly and 

 the three intermediate ones very closely. The time of revolution 

 is estimated at about 2370 years, but it does not appear that the 

 comet was observed at its previous return to perihelion. The 

 elements above given are a very close approximation to the true 

 orbit inasmuch as Dr. B. von Engelhardt observed the comet at 

 his private observatory, Dresden, so late as July 15th when the 

 correction to the ephemeris was found to be only + 2*16 s. in right 

 ascension, and — 14-6" in declination. The comet was at no time 

 a very conspicuous object to the unassisted eye and its maximum 

 length of tail was only about three degrees. 



Comet II., 1888. 

 This is a return of the well-known comet of Encke. This object 

 was originally discovered by Mechain at Paris, on January 17th 

 1786. It was not again seen till the return of 1795, when Miss 

 Caroline Herschel, sister of the celebrated Sir William Herschel, 

 detected it on November 7th of that year. At the return of 1805 

 the comet was again found by Thulis at Marseilles on October 1 9th, 

 but no suspicion appears to have been entertained that these three 

 appearances were of one and the same body. From the observations 

 in 1805 Encke computed an elliptic orbit with a period of about 

 twelve years. On November 26th 1818, the well-known Pons of 

 Marseilles discovered a small comet which was observed for nearly 

 seven weeks. These observations served as a better foundation 

 for the determination of elliptic elements, and Encke found that 

 they gave a period of about 3^ years. He also showed that the 

 perihelion distance and the position-elements of the orbit agreed 

 closely with those of the Comets of 1786, 1795 and 1805. Between 

 1786 and 1818 the comet had therefore passed through perihelion 



