on Mufcular Motion. o r 
power to the particles of the moving part of greater attraction. 
I (hall illuftrate this idea by fuppofing, that there is a machine 
moving by various powers, either original or communicated ; 
and that in this machine there are two magnets, which by 
their attractive power have come to a given diftance from one 
another, but have been prevented from coming nearer by lome 
power endeavouring to draw them back. A much Wronger 
magnet applied to a part of the machine, in a certain manner, 
fo as not to touch either of the two already there, nor to affeCt 
any other part, may increafe their power of attraction, fo as 
to make them overcome the refinance, and come nearer one 
another *. 
In the fame manner, I apprehend, that an application made 
to the (kin of the abdomen may, and often does, occafion the 
aCtion of the inteftines to take place, without any efFeCt what- 
ever on the intermediate parts ; but that it (imply excites the 
attraction of the particles of the moving parts of the in- 
teftines ; certainly a part of the matter through which the in- 
fluence is to pafs, vi%y the mucus and fcarf (kin, is actually 
inanimate matter. 
In certain cafes of original motion, there Is attraction, or 
the coming nearer of particles only. In others, there is not 
only attraction, but oppofite repulfion ; the cafes of which are 
imnecefiary to enumerate to this Society. In the attraction of 
life there is no oppofite repuldon ; all the motions of the body 
are produced entirely by the force of particles coming nearer- 
one another. When this force diminifhes, or the aCtion goes 
oft, and leaves the part entirely to its tone, the particles of the 
moving part are by no means repulfed from one another, but 
* I do not mean to infinuate, in the fmalleft degree, that the powers of the 
body at all depend on, or havs any thing to do with, magnet ifm. 
