18 PHYSIOLOGICAL EFFECTS 



CHAPTER II. 



PHYSIOLOGICAL EFFECTS OF ELECTRICITY AND 

 GALVANISM ANALOGY WITH NERVOUS IN- 

 FLUENCE. 



WE come in the next place to consider the physiological 

 effects of Electricity under its different forms ; and first of that 

 modification we call FRICTIONAL or STATIC Electricity. 



It has long been suspected, and indeed rendered almost certain 

 by a variety of facts, that the electrical state of the atmosphere 

 has an appreciable influence on the animal economy. The lower 

 animals s'eem aware of an approaching thunder-storm, as would 

 appear from the uneasiness which they manifest, the cries which 

 they utter, and their running about in a state of alarm, in search 

 of shelter. 



" Prone to the lowest vale, the aerial tribes 



Descend: the tempest loving raven scarce 



Dares wing the dubious dusk. In rueful gaze 



The cattle stand, and on the scowling heavens 



Cast a deploring eye :" 



Many individuals also of the human species, particularly those 

 labouring under certain chronic complaints, or who possess what 

 may be called a great degree of mobility of the nervous system, 

 experience at such times very peculiar sensations. Observations 

 such as these, and many others of a similar description which 

 might be quoted, demonstrate very completely that the animal 

 machine is frequently sensibly affected by the electricity of the 

 atmosphere ; and there is even nothing improbable in the con- 

 jecture, which has often been hazarded, that the salubrity or 

 insalubrity of particular districts and seasons, the existence and 

 character of epidemic diseases, are in some way connected with, 

 if not immediately dependent on, the same influence. 



The effects of artificially produced Electricity on animals vary 

 according to the mode of applying it. If the individual be insu- 

 lated, and placed in connexion with the prime conductor of a 



