Animal Intelligence 



our purpose all these matters count little, and we may take 

 the general slope of the curve as representing very fairly 

 the progress of the association. The slope of any particular 

 part of it may be due to accident. Thus, very often the 

 second experience may have a higher time-point than the 

 first, because the first few successes may all be entirely 

 due to accidentally hitting the loop, or whatever it is, and 

 whether the accident will happen sooner in one trial than 

 another is then a matter of chance. Considering the general 

 slope, it is, of course, apparent that a gradual descent say, 

 from initial times of 300 sec. to a constant time of 6 or 8 sec. 

 in the course of 20 to 30 trials - -represents a difficult 

 association; while an abrupt descent, say in 5 trials, from a 

 similar initial height, represents a very easy association. 

 Thus, 2 in Z, on page 57, is a hard, and i in I, on page 49, 

 an easy association. 



In boxes A, C, D, E, I, 100 per cent of the cats given a 

 chance to do so, hit upon the movement and formed the 

 association. The following table shows the results where 

 some cats failed: 



TABLE I 



No. CATS TRIED No. CATS FAILED 



The time-curves follow. By referring to the description 

 of apparatus they will be easily understood. Each mm. 

 along the abscissa represents one trial. Each mm. above 

 it represents 10 seconds. 



These time-curves show, in the first place, what associa- 



