78 Dr. Herschel on the Power of 



the reach of magnifying power, could only profit by the supe- 

 riority of the other power. 



Nov. 21, 1791. 40-feet reflector ; power 370. 



" The black division upon the ring is as dark as the heavens 

 " about Saturn, and of the same colour." 



" The shadow of the body of Saturn is visible upon the ring, 

 " on the following side ; its colour is very different from that 

 " of the dark division. The 5th satellite is less than the 3d; it 

 " is even less than the 2d." 



20-feet reflector ; power 300. 



" The 3d satellite seems to be smaller than it was the last night 

 " but one. The 4th satellite seems to be larger than it was the 

 " 19th. This telescope shews the satellites not nearly so well 

 " as the 40-feet." 



Here, the magnifying power being nearly alike, the superi- 

 ority of the 40-feet telescope must be ascribed to its penetrating 

 power. 



The different nature of the two powers above mentioned being 

 thus evidently established, I must now remark, that, in some 

 respects, they even interfere with each other; a few instances of 

 which I shall give. 



August 24, 1783. I viewed the nebula north preceding 

 Flamsteed's 1 Trianguli, discovered by Mr. Messier, in 1764. 



" 7-feet reflector; power 57. There is a suspicion that the 

 " nebula consists of exceedingly small stars. With this low 



