Teat 

 250 



200 



150 



100 



50 



Stim.lOO 



200 



300 



400 



500 



Fig. 5. A graphic representation of the relation of strength of electrical stimulus to condition of vis- 

 ual discrimination and rapidity of learning. Ordinates represent value of electric stimulus in units of 

 stimulation; abscissas represent the number of tests given. Curve 7 represents the results of the experi- 

 ments of Set I. Each dot indicates a value of stimulus which was used in the experiments. 

 For example, the first dot to the left in curve / signifies that the stimulus whose value was 125 

 units gave a perfect habit, in the case of the four individuals trained, with 187 tests; the second dot, that 

 for the stimulus value of 300 units 80 tests were necessary; and the third that for the stimulus value of 

 500, 155 tests. Curves II and III similarly represent the results of the experiments of sets II and 

 III, respectively. 



