INDUCTION SHOCKS 
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CHAPTER I 
THE CHARACTERISTICS OF INDUCED CURRENTS 
Introductory. The inductorium has become one of 
the most familiar and most useful instruments in the 
physiological laboratory. There are few physiological 
researches which do not involve artificial stimulation of 
tissues; and for the production of stimuli induction 
shocks are in most cases the first choice. They are 
easier to use and they subject the stimulated tissue to 
less permanent modification than do other forms of 
artificial stimulus. Induction shocks are, however, very 
variable in intensity; and as commonly used there is 
no means of knowing or of stating their physiological 
effectiveness in other than the most general terms. An 
induction shock is weak, medium, or strong. More 
closely than that the user does not attempt to describe it. 
This lack of knowledge as to the strengths of the 
stimuli employed is often a serious handicap in the pros- 
ecution of individual researches, particularly such as 
call for the use of stimuli of varying strengths. It also 
