MENTAL LIFE OF MONKEYS AND APES 95 



Although active at first on April 6, he soon wearied of his 

 task and quit work. The same was true on April 7, and again 

 on the 8th and 9th. On these days, although hungry, he did 

 not care to enter the large cage and worked only a few minutes 

 each day, seldom making more than two or three half-hearted 

 attempts to obtain the banana. His attitude toward the task 

 had changed completely, in that hopelessness had taken the 

 place of eager expectancy. By the 13th of April he had so 

 nearly given up voluntary efforts to solve the problem that it 

 seemed worth while to test his ability to get the idea by watch- 

 ing the experimenter. For this purpose the following test of 

 imitation was made. 



On the morning of April 14, having placed a banana in the 

 usual position, I took Julius into the large cage, dragged the 

 two boxes to the proper position beneath the banana, placed 

 the smaller one upon the larger one and then climbed up on 

 them to show the ape that I could reach the banana. I then 

 stepped down and gave him a chance to climb on the boxes. He 

 did so immediately and obtained the food. 



Another piece of banana was supplied, the boxes were placed 

 in distant corners of the cage, and fifteen minutes were allowed 

 Julius so to place them that he could obtain his reward. He 

 gave no indications of having profited by my demonstration, 

 but worked with the boxes singly, usually with the larger one. 



On April 16, with the banana in position and the two boxes 

 also in the cage, Julius was admitted and allowed to work for 

 five minutes, but again without success. I then placed the 

 boxes properly for him and he immediately climbed up and 

 got the banana. While he was eating, the boxes were carried 

 to distant comers of the cage and another banana placed in posi- 

 tion. Now thirty minutes were allowed him for unaided work 

 on the problem. As formerly, the larger box was used repeatedly 

 and attempts to reach from the side of' the cage appeared, ' but 

 there was no tendency to try to use the two boxes together. 

 He worked fairly persistently, however, and showed clearly the 

 stimulating and encouraging effect of aid from the experimenter. 



Once more, on April 17, Julius was taken into the cage and 

 allowed to watch me place the boxes in proper position. He 

 then climbed up and obtained the desired food. After the bait 

 had been renewed and the boxes displaced, he immediately tried 



