58 RESPONSE IN THE EIVING AND NON-LIVIAG 
the strain is not completely removed after any single 
stimulation of the series. That recovery is partial is 
seen by the gradual shifting of the base line upwards. 
In the former case the base line is horizontal and re- 
presents a condition of complete equilibrium. Now, 
however, the base line, or line of modified equilibrium, is 
tilted upwards. Thus even in this case if we measure 
the heights of successive responses from the line of 
absolute equilibrium, they will be found to increase with 
increasing stimulus. Ordinarily, however, we make no 
allowance for the shifting of the base line, measuring 
response rather from the place of its previous recovery, 
or from the point of modified equilibrium. Judged in 
this way, the responses undergo an apparent diminution. 
