PHYSICAL AND LTTXRARY. 27 



phical to fuppofe the exigence of a caufe, 

 when we cannot point out a fihgle efFecl 

 that rcfults from it, and from no otkef 

 caufe. 



But there is another experiment of the 

 veryeafieft operation, and which is liable 

 to no ambiguity. Let a body of any de- 

 termined weight be fufpended by a thread 

 or rope fix'd to a hook in the ceiling ; The 

 leaft conceivable force will put this body 

 in motion. If any refiftance at all be felt, 

 it ought to be attributed to the d^nfity of 

 the air, not to the body. And indeed 

 thefe experiments infer, no more than 

 what is admitted by every philofopher, 

 that the fmalleft forc« is fufficient to move 

 the greateft body. It is acknowledged, 

 that, were the globe of the earth fufpend- 

 ed by a chain, there is no force fo fmall 

 which it would not yield to. Thefe, and 

 fuch like experiments, look as if matter 

 had no attachment to reft, no vis rejiftcn- 

 tiae, but that it readily yielded to motion. 

 That a body is put in motion by the ve- 

 ry fmalleft force, and yet that it refifts a 

 change from reft to motion, are propofi- 



tions 



