[ 40 ] 
will deftroy the Motion of the hinder Parts $ and 
poflibly this may happen from the great Diftenfion 
of the Aorta above the Ligature, prefling upon the 
Nerves which go to the lower Parts. 
XCIV. 
It is certain indeed, when all the Blood is inter- 
cepted the Fibres will Loon .collapfe, and grow flac- 
cid, and mufcuiar Motion will ceafe, merely for 
Want of the Warmth, Supplenefs, and Diftenfion 
which the Mufcles receive from the Blood. But 
what I think mod reafonable is, that the Blood is 
no Way concerned as an efficient Caufe in purfing 
up and contra&kig the Fibres s it rather by its Mo- 
tion through the Mufcles, ads as an Antagonift to 
their Contradion, by extending and diftending them$ 
for the Blood, by the 'Diaftole and Syftole of the 
Arteries, is continually urging on its Raffage through 
tfie Mnfcles. ' 
%C¥. 
Thus I have endeavour’d to deduce and illuftrate 
the Caufe of mufcuiar Motion from true Principles., 
by purfuing only thofe Laws of Nature, which our 
great Philofopher Sir Ifaac Newton has in fo fur- 
prifing a manner difcovercl to us. But I am far 
from thinking this a complete Account 5 I know it 
requires more Experiments, and better Reafonings 
than I am Mafter of, to explain it as it ought 3 and 
even after all, there are, and ever will be, fome 
Things above the Rea^h of our Capacities to demon- 
ftrate. 
