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dies which are inhabited, will have forms and pow- 

 ers no less suited to their situations than ours, 



" And constitutions fitted for that spot, 



Where Providence, all-wise, has fix'd their lot." 



The sun, although generally considered as fixed, 

 is known, by his spots, to make a revolution on his 

 axis in somewhat less than our month, and is like- 

 wise said to be agitated by a small motion round 

 what is called the centre of gravity of the Solar 

 System His motion, however, is so comparatively 

 small, that he may, indeed, be said to be fixed, with 

 respect to 



The Planets. 



Of the planets which have yet been discovered, 

 the first, or nighest the sun, is Mercury His dia- 

 meter is computed to be less than the half of that of 

 the earth, and his year is not quite so long as three 

 of our months: the light and heat of this planet are 

 supposed to be about seven times greater than the 

 earth receives ; yet he is said to move at the rate of 

 more than 109,000 miles in an hour! Being so nigh 

 the sun, Mercury is seldom seen; but when he is, it 

 is a little after sunset, and before sunrise, and he 

 appears to em : c a bright white light 



The diameter of Yenus is somewhat less than that 

 of the earth, and her year is not quite eight of our 

 months In the heavens she moves next in order 

 ta Mercury, and, notwithstanding she is supposed to 



