14 ATTRACTION. 



It is by this attraction that the sap rises in trees 

 and plants, and that water will ascend in a sponge, 

 or other porous substance. 



The attraction of gravitation or gravity is the 

 force which all the masses of matter exert upon 

 each other at all distances. 



The reason why a body falls to the ground was 

 long unknown, and it was Sir Isaac Newton who 

 first accounted for it, by the attraction of gravitation. 



This idea is said to have occurred to him, on 

 observing an apple fall whilst sitting in his garden, 

 which is a striking instance of the use to which a 

 man of genius turns every observation he makes : 

 he supposed that the stone fell towards the earth, 

 because it was drawn, or attracted by it. By re- 

 flecting upon this principle, he extended it to 

 account for many of the phenomena which till 

 then could not be explained. 



It is now considered as one of the laws of 

 nature, that every particle of matter is endued 

 with an attractive power, which it exerts at all 

 distances on every other particle, though the » 

 attraction diminishes in proportion to the distance. 

 By this attraction, the heavenly bodies are re- 

 tained in their places by their action on each 

 other; the planets and comets all gravitating 

 towards the sun and towards each other, as well 

 as the sun towards them, and that in proportion to 

 the quantity of matter in each. 



If two bodies, which contain equal quantities of 

 matter, were placed at ever so great a distance from 

 one another, and then left at liberty in free space, 

 and if there were no other bodies in the universe 

 to affect them, they would fall equally swift towards 

 each other, and would meet in a point which was 

 half way between them at first. Or if two bodies, 



