104 HISTORY OF ASTRONOMY. 



seen more than two hours. On the following evening 

 it was gone from the place where he had seen it the 

 night previous. 



There are five instances in which Herschel observed 

 what he called " an exterior satellite." 



On the 9th of February, 1790, a supposed third satel- 

 lite was remarked in a line with the planet and the 

 second satellite, and about twice the distance of the 

 second satellite. On the 12th the supposed satellite of 

 the 9th was not in the place where it was then seen. 



On the 31st of January, 1791, a satellite was observed 

 in opposition to the second, and at about double the dis- 

 tance from the planet. 



On the 26th of February, 1792, a star toward the south, 

 at double the distance of the first satellite, was pointed 

 out, but it has not been accounted for in succeeding 

 observations. 



On the 5th of March, 1796, Herschel recorded, " I sus- 

 pected a very small star between c and 7i, which was not 

 there last night. I had a pretty certain glimpse of it. 

 With 600 I see the satellite c better than before, but can 

 not perceive the suspected small star." 



On the llth of February, 1798, an exterior satellite 

 was observed, and its situation measured. 



There are four instances in which Herschel observed 

 what he called " the most distant satellite." 



On the 28th of February, 1794, Herschel remarked a 

 very small star which he did not see on the 26th. 



On the 27th of March, 1794, he obtained lucid 



