MATTEE AND FORCE. 57 



amber were credited with pushing and pulling, or, in 

 other words, with exerting force. 



In the time of the great Lord Bacon the margin of 

 these pushes and pulls was vastly extended by Dr. 

 Gilbert, a man probably of firmer scientific fibre, and 

 of finer insight, than Bacon himself. Gilbert proved 

 that a multitude of other bodies, when rubbed, exerted 

 the power which, thousands of years previously, had 

 been observed in amber. In this way the notion of 

 attraction and repulsion in external nature was ren- 

 dered familiar. It was a matter of experience that 

 bodies, between which no visible link or connection 

 existed, possessed the power of acting upon each other; 

 and the action came to be technically called ' action at 

 a distance.' 



But out of experience in science there grows some- 

 thing finer than mere experience. Experience fur- 

 nishes the soil for plants of higher growth; and this 

 observation of action at a distance provided material 

 for speculation upon the largest of problems. Bodies 

 were observed to fall to the earth. Why should they 

 do so? The earth was proved to revolve round the 

 sun; and the moon to revolve round the earth. Why 

 should they do so? What prevents them from flying 

 straight off into space? Supposing it were ascertained 

 that from a part of the earth's rocky crust a firmly 

 fixed and tightly stretched chain started towards the 

 sun, we might be inclined to conclude that the earth 

 is held in its orbit by the chain that the sun twirls the 

 earth around him, as a boy twirls round his head a 

 bullet at the end of a string. But why should the 

 chain be needed? It is a fact of experience that bodies 

 can attract each other at a distance, without the inter- 

 vention of any chain. Why should not the sun and 

 earth so attract each other? and why should not the 



