CHAP. 5. ON VITAL FUNCTIONS. 181 



people feel uncomfortable, and produces head- 

 aches in persons who are subject to them. 

 Similar changes have the most violent effects 

 when they happen about the new or full Moon. 

 It is difficult to ascertain in what degree the 

 directions and changes of Wind are under the 

 influence of electricity, but there are many 

 circumstances which would incline one to be- 

 lieve that these changes are dependent on some 

 similar principle to that which causes atmo- 

 spheric diseases in the human body ; for certain 

 Winds, as well as certain changes of Wind, are 



cury may increase an aeriform perspiration into the cavity of 

 the shaft, if such an one exist ; it may also rectify a disordered 

 state of the digestive organs, and, by that means, cause a 

 stronger and more healthy action of the vascular system, and 

 of the vessels of the hair among the rest. I think it by no 

 means follows that hairs are not vascular, because we cannot 

 demonstrate their vessels. On this subject, I think, we may 

 reason thus : if all nourishment be effected by the action of 

 vessels, it follows, either that there must be some vessels not 

 nourished at all, or that vascularity must extend ad infinitum. 

 Can we demonstrate those small arteries which ramify in the 

 coats of, and nourish the smallest vasa vasorum ? Such reflec- 

 tions as these ought to prevent our denying organization to 

 any part of a living body, even to the cuticle or the enamel 

 of the teeth. Minute inquiries like these in all the sciences, 

 would end, when pushed to the extent of human knowledge 

 in metaphysical questions like the above. 



