[ 2 S ] 
LV. 
Before the Laws of Nature, and the Animal 
©economy were fo well known as they are now, I 
don't wonder that the veficular Scheme was thought 
a reafonable one, till it came to be examined by 
ftridt Rules and Experiments. The common Experi- 
ment of raifing Weights by blowing up Bladders 
might feem, at firft Sight, a very feafible Way of 
explaining mufcular Motion ; and without Doubt 
this firft of all gave Birth to the veficular Hypcthejis . 
LVL 
i 
But the Eallacy of this Experiment was not dis- 
cover'd for want of attending to the Difference be- 
tween Bladders which have been already blown up, 
and dried, and fuch as are recent and fupple. 
LVII. 
i 
If a String of dry Bladders, which have been once 
diftended as far as they could bear without burfting, 
and are now again fqueezed clofe, and ftretched out 
only in their Length, by means of a Weight hung 
at their Bottom ; 1 fay, if fuch a String of Bladders 
be blown up, it will undoubtedly diftend their tranf- 
verfe Diameters fo as to raife up the Weight: But 
in all tender yielding Veficles, fuch as the mufcular 
Fibres mod certainly are, in their laft, or fmalleft 
Order, it is well known, that if they were to be 
inflated with Air, or any fuch-like Matter, it would 
D diftend 
