4 BiograpJtkal Memoir of Sir William Herschcl. 



of its distance from the earth may be formed from the fact, that 

 light, which travels at the rate of 70,000 miles in a second, takes 

 about two hours and a half to come from it to us. 



Herschel, and, previous to his time, IJgiminique Cassini anJ 

 Galileo, wished to give to the celestial bodies which they disco- 

 vered, the names of the princes who had favoured their la- 

 bours ; several astronomers have proposed the names of the first 

 observers ; but the names of the recently discovered planets have 

 not been dictated either by justice or gratitude ; they have been 

 drawn from the confused remembrance of fables that have be- 

 come unintelligible. The new planet received from Herschel the 

 name of the Georgium Sidus; while astronomers at first gave It 

 that of Herschel, but afterwards hesitated with regard to the 

 names of Cybele, Neptune, and Uranus, the last of which ulti- 

 mately prevailed. 



When the motion of this planet was calculated, the points of 

 the heavens which it had successively occupied during the pre- 

 ceding century, could be pointed out ; and thus, on consulting 

 the collections of preceding observations, it was discovered that 

 Flamsteed, Mayer, and Lemonier, had pointed out, in those 

 very places, stars which are now no longer to be seen there. 

 Their observations evidently refer to Herschefs planet, which 

 they had not distinguished from the fixed stars. 



The cosmological opinions of Kepler, Lambert, and Kant, led 

 them to suppose the existence of an eighth planet between Jupi- 

 ter and Mars. The comparison that had been made of the dis- 

 tances of each planet from that of Mercury, which is the nearest 

 to the sun, suggested a similar remark. The discovery of Uranus 

 rendered the idea much more plausible, and excited astronomers 

 to new researches. The result was, that, in the great interval 

 between Mars and Jupiter, and at a distance differing little 

 from what had been indicated, there were discovered four small 

 stars, which look like so many separated parts of the same pla- 

 netary body, and which can only be perceived with the aid of 

 telescopes. These important observations were made about the 

 commencement of the present century ; we owe them to Piazzi, 

 Olbers, and Harding. 



The astronomical labours of the music master of the Bath 

 Chapel, the perfection of his instruments, which were all his own 



