1 88 HERSCHEL AND HIS WORK 



the satellites of the Georgium Sidus, when, after 

 throwing aside the speculum, they stood broad before 

 us." 



From observations continued on Uranus for fifteen 

 years, Herschel first suspected, and then became con- 

 vinced that other satellites besides the two, which he 

 discovered in 1787, attend the planet on its journey 

 round the sun. It was labour of love not lost, or 

 grudgingly given, but the fruits it yielded were Dead 

 Sea apples with a fair outside and rottenness within. 

 He believed he saw other four moons circling round 

 Uranus apparently in an opposite direction to other 

 planets, that is, from east to west, not from west to 

 east. He also suspected that it had a ring round it, 

 or two rings; then he gave up the idea; then he 

 entered in his journal, " When the satellites are best in 

 focus, the suspicion of a ring is the strongest " ; and 

 nine months after he adds, " The planet is not round, 

 and I have not much doubt but that it has a ring." 

 He used " successively powers rising from 240 to 2400," 

 more than two years after, " without any suspicion of 

 a ring." A fortnight later he tried magnifying powers 

 of 2400 and 4800. In conclusion he believed in the 

 four new satellites, but gave the ring up. A traveller 

 in unexplored regions of the heavens may thus be as 

 much the victim of a mirage as a wanderer in the 

 thirsty deserts of earth. But a singular thing was 

 observed: these moons of Uranus became invisible 

 when they approached the planet, which those of 

 Jupiter and Saturn never did till the planet got be- 

 tween them and us. What was the reason ? 



The cause is in the eye of the observer himself. It 

 requires to adapt itself to the light which falls on the 



