282 



MIND IN EVOLUTION 



CHAP. 



(2) He did recognise obstacles when, so to say, they 

 stared him in the face ; and then devised means of his own 

 for dealing with them. This was particularly noticeable 

 in the slackening of the string. He must in some obscure 

 fashion have felt that the string was pulling against him 

 when he tried to unfasten the hook ; and for this he 

 found the appropriate remedy. This was therefore a good 

 case of " original application." 



(3) His first success was one of the most striking 

 examples that I have seen of the effect of a sudden turn of 

 attention. Though he had pulled off the hook before, and 

 also pushed back the bolt, he had clearly never put two 

 and two together. For some inscrutable reason, the move- 

 ment of my hand suddenly seemed to bring the whole 



thing into his mind. He 

 at once took off the hook, 

 pulled back the bolt, 

 opened the box, and did 

 not fail again. 



5. On the other hand, 

 both monkeys failed in 

 another experiment with 

 a hooked rope. I passed 

 a rope round a stanchion 

 outside the chimpanzee's 

 cage, tied a box to one 

 part of it, and gave the free end to the chimpanzee. 

 The other end I hooked to a bar of his cage. The result 

 was that he could pull the free end as hard as he pleased, 

 but it would have no effect unless he took the hook off. 

 In this he failed, though I repeatedly took the hook off 

 myself, thinking that he might learn to see the difference 

 which it made. Jimmy failed equally in a similar 

 experiment which I arranged for him. Both monkeys, 

 after trying one rope, would try the other ; and it was 

 interesting to note how, on at least one occasion, the 

 chimpanzee, after having lost the free end of the rope by 

 pulling hard at the other, kept both ropes in his hands 

 while he pulled. The same monkey showed consider- 

 able, but from the experimenter's point of view perverted, 



