Attraction. 15 



course of its rotatory diurnal motion. The earth 

 has therefore been compared to a large magnet, 

 which attracts all smaller bodies towards its cen- 

 tre. This is the true cause of weight or gravity 

 (which are correlatives). All bodies are drawn 

 towards the earth by the force of its attraction ; 

 and this attraction is exerted in proportion to the 

 quantity of solid matter which any body contains. 

 Thus, when two bodies are placed in opposite 

 scales, and we see one preponderate, we say it is 

 heavier than the other ; in truth, that it contains 

 a greater quantity of solid matter. For as every 

 particle of matter is attracted by the earth, the 

 greater number of such particles any body con- 

 tains the more forcibly it will be attracted. 



The attraction of matter is universal : so that 

 not only does the earth attract all bodies upon it, 

 or near it ; but all such bodies reciprocally at- 

 tract the earth. Nay, farther, the earth attracts 

 all bodies in the universe, and they, again, all 

 attract the earth. Every particle of matter exerts 

 an attractive energy upon every other particle ; 

 and each of the bodies into which particles are 

 grouped attracts every other body. Thus, the 

 sun attracts all the bodies in the planetary system ; 

 and they, in their turn, attract the sun and each 

 other. The fixed stars, again, attract each other, 

 and our sun ; they also attract, and are attracted 

 by, the several bodies to which they probably 

 form distinct centres. The attractive forces of 

 bodies upon each other, are directly proportional 



