99(V PLANET SATURN, 



VIIL 



Observations and Remarks on the Figure, (he Climate, 

 and the Atmosphere of Saturn, and its Ring, By 

 WiLftiAM Herschel, LL.D. F.R.S*, 



Changes in the IvJLY last year's observations on the singular figure of 

 appearance of Saturn having drawn the attention of astronomers to this 

 subject, it may be easily supposed that a farther investi- 

 gation of it will be necessary. We see this planet in the 

 course of its revolution round the sun in so many various 

 aspects, that the change occasioned by tlie different situa* 

 tions in which it isvicAved, as far as relates to the ring, 

 has long ago been noticed ; and Huygens has given us ii, 

 very full explanation of the cause of these changes +. 

 I— affect' the ^^ the axis of the planeCs equator, as well as that of 



body of the the ring, keeps its parallelism during the time of its re- 

 SlThcMnJ^" volution about the sun, it follows that the same change of 

 situation, by which the ring is affected, must also pro- 

 duce similar alterations in the appearance of the planet ; 

 but since the shape of Saturn, though not strictly spheric 

 cal, is very different from that of the ring, the changes 

 occasioned by, its difTcrent aspects will be so minute that 

 only they ^^an expect to perceive them who have been in 

 the habit of seeing very small objects, and are furnished 

 with instruments that will show them distinctly, with a 

 very high and luminous magnifying power. 



r • • ^ If the equator of the planet Jupiter were inclined to 

 ■faipiter IS not ^ o t 



so affected, be- the ecliptic like that of Saturn, I have no doubt but that 

 cause its equa- ^^ should see a considerable change in its figure during 

 the'ecliptLy*" the time of a synodical revolution ; notwithstanding the 

 spheroidical figure occasioned by the rotation on its axis 

 has not the extended flattening of the polar regions that 

 I have remarked in Saturn. But since not only the po- 

 sition of theSaturnian equator is such that it brings on a 

 periodical change in its aspect, amounting to more than 



* Philos. Trans. 1806. 

 f Sec Syttema Sattirnium^ page s^t where the changes of the ring 

 are represented by a plate. 



62 degrees 



