Lest on xxxm.] SEASONS. 



Flings from the sun direct the flaming day; 

 Feeds ev'ry creature ; hurls the tempest forth : 

 And as on earth this grateful change revolves, 

 With transport touches all the springs of life." 



It may have been observed that, when explain- 

 ing the nature of the tides, I said, " The earth is 

 nearer the sun in Winter than in Summer." This 

 may to many persons appear improbable, but it is 

 absolutely fact : for the apparent diameter of the 

 sun is about 32' 48" on the shortest day, and only 

 31 30" on the longest : whence it is manifest that 

 his distance from us must be less in the former 

 case than in the latter. But the effects occa- 

 sioned by the difference of distance are more than 

 counterbalanced to the inhabitants of the earth's 

 northern hemisphere : for, though the sun in 

 Summer be farther from us ; yet, on account . 

 of his being more nearly in a vertical position, 

 his rays fall more directly on any part, and 

 of course are denser and thicker; and this, not 

 nly because the same quantity of rays fell on 

 a less space of the earth, but because they are 

 not so much refracted and attenuated by the at- 

 mosphere, as when they fall upon it more ob- 

 liquely. 



The diversity of seasons is occasioned by the 

 earth's annual motion in her orbit ; and in this 

 motion two peculiar circumstances must be well 

 understood, because on their combination the 

 whole phaenomena depend. " 1. The earth's axis 

 does not always keep the same relative situation 

 with regard to the sun as the centre of its orbit ; 

 L 2 but. 



