354 



THE OUTGO OF ENERGY 



The Ergograph. 1 A flat, steel spring provided 

 with a writing point is fastened in a stout iron support 

 clamped to the table (Fig. 61). The second, third, and 

 fourth fingers of the subject's hand are fastened with 

 tapes to the wooden support. Upon the index finger 



FIG. 61. The ergograph ; also employed for recording the isometric and 

 isotonic contractions of human muscle. 



near the distal end of the middle phalanx is placed a 

 rod the length of which is adjustable. The point of 

 the rod passes through a rubber ring and presses 

 against the under side of the spring. When the point 



1 First described in the " Introduction to Physiology," 1901, 

 p. 220. 



