OF NATURE. 253 



power of the fun, and obliged to circulate a- 

 round him. Saturn, Jupiter, Mars, the Earth, 

 Venus, Mercury, and the Sun, occupy the fmali 

 part of the heavens which we call our Un'wcrfe. 

 All thefe planets with their fatellites, moving 

 with rapidity in the fame direction, and nearly 

 in the fame plane, compofe a wheel of an im- 

 menfe diameter, whole axis fupports the whole 

 weight, and which, by the celerity of its own 

 rotation, muft inflame and diffufe heat and light 

 to every part of the circumference. As long as 

 thefe movements continue, (and they will be e- 

 ternal, unlefs the hand of the prime Mover inter- 

 pofe, and exert as much force to deftroy, as was 

 neceffary to create them), the fun will burn, and 

 fill all the fpheres of this univerfe with his fplen- 

 dour : And as, in a fyftem, where all bodies at- 

 tract each other, nothing can be loft, or remove 

 without returning, the quantity of matter remain- 

 ing always the fame, this fertile fource of light 

 and life can never be dried up or exhaufted; for 

 the other funs, which likewife dart forth their 

 fires continually, reftore to our fun as much light 

 as they receive from him. 



The comets, which are much more numerous 

 than the planets, and, like the latter, depend on 

 the power of the fun, prefs alfo on this common 

 focus, and, by augmenting the weight, increafe 

 the inflammation. They conftitute a part of our 

 univerfe; for, like the planets, they are fubjec- 

 ted to the attraction of the fun. But, in their 



projectile 



