42 Thaddeus L. Bolton and Elconora T. Miller 



practice had been taken, so that the pauses would have about the 

 same value that they would have for an unpracticed reagent. A 

 similar set of circumstances seemed to affect the work of M.'s 

 left hand in the second period, making the second pause less 

 valuable for recuperation. 



The recuperative value of these pauses was studied in another 

 way. When an observation was begun, the contractions of the 

 finger were continued until complete exhaustion was reached, 

 that is, until no further contractions were possible. The last 

 contractions in any fatigue curve were therefore very short and 

 made with great manifestations of effort, all the muscles of the 

 body joining sympathetically in the movement, and their activity 

 increased in violence and extent as the exhaustion point was 

 approached. It was thought that the amount of work the con- 

 tracting finger was accomplishing was very small in proportion 

 to the actual expenditure of energy, that is, there was a great 

 waste of energy here, and that if work were suspended as soon 

 as it became clear, through the amount of effort that was neces- 

 sary to make a contraction, that the exhaustion point was near, 

 the waste of energy would be stopped. Upon the approach of 

 exhaustion the reagent gradually falls into the condition of an 

 un inured reagent. The work produces in the arm temporarily 

 the feelings of muscle soreness and stiffness which ordinarily 

 arise in the members of an unpracticed reagent. By the avoid- 

 ance, then, of this condition, it was thought that greater work 

 capacity would be shown. Therefore, observations in which the 

 reagent ceased to contract the finger as soon as the symptoms 

 of fatigue became strongly apparent, were alternated with others 

 in which each fatigue curve was carried quite to the exhaustion 

 point. 



In the following table, the averages of the curves which were 

 carried to the exhaustion point are compared with those that were 

 stopped short of the exhaustion point. They are designated "to 

 exhaustion," and "not to exhaustion." 



1 20 



