SECT. XII. i. OF STIMULUS AND EXERTION. 65 



nefs. Pulfe quickened by rifing out of bed. 8. To 



the greateft degree of quiefcence apply the leajl flimulus. 



Giherwife paralyfts or inflammation of the organ en- 

 fues. Gin, wine, blifters^ dejlroy by too great ftimu- 



lation in fevers with debility. Intoxication in the 

 Jlightejl degree fucceeded by debility. Golden rule for 



determining the beft degree of ftimulus in low fevers. 



Another golden rule for determining the quantity of 

 fpint, which thofe, who are debilitated by drinking 



it, may fafely omit. 



I. Of Jibrous contraclion. 



t. IF two particles of iron lie near each. other 

 without motion, and after wards approach each other; 

 it is reafonable to conclude that fomething befides 

 the iron particles is the caufe of their approxima- 

 tion ; this invifible fomething is termed magnetifm. 

 In the fame manner, if the particles, which com- 

 pofe an animal muicle, do not touch other in the 

 relaxed ftate of the mufcle, and are brought into 

 contact during the contraction of the mufcle ; it is 

 reafbnable to conclude, that fome other agent is 

 the caufe of this new approximation. For nothing 

 can act, where it does not exift ; for to act includes 

 to exift ; and therefore the particles of the mufcu- 

 lar fibre (which in its ftate of relaxation are fup- 

 pofed not to touch) cannot affect each other with- 

 out the influence of fome intermediate agent ; this 

 agent is here termed the fpirit of animation, or 

 fenforiai power, but may with equal propriety be 

 termed the power, which caufes contraction ; or 

 may be called by another name, which the reader 

 may choofe to affix to it. 



The contraction of a mufcular fibre may be com- 

 pared to the following electric experiment, which 

 is here mentioned not as a philotbphical analogy, 

 but as an illuftration or fimile. to facilitate the coo* 



ceptioji 



