336 ^Journal of Comparative Neurology and Psychology. 

 Experime72t II. Pushing Open a Sivinging Door. 



Method. — A wooden box,whose length was 96 cm., breadth 37cm. 

 and depth 14 cm. was covered with wire netting of a centimeter 

 mesh. The box was divided into two parts by a wooden partition, 

 and in the middle of this partition was a swinging door 10 cm. 

 wide and 6 cm. high, which was made of the same material as the 

 top of the box. 



The act to be performed was to push the swinging door open 

 and get the food placed in plain sight just beyond the door. 



Results. — No. 4 was put into the box alone for ten minutes, but 

 before the end of the time he had ceased to make any effort to get 

 out. No. 3, who had already been taught to go through the door, 

 was now put in with him. Although No. 4 saw No. 3 go through 

 the door repeatedly, he did not succeed in getting through. The 

 next day the experiment was repeated but the results were negative, 

 as No. 4 would watch No. 3 go through the door but would make 

 no effort to follow him through. No. 3 was now taken out and 

 No. I and No. 2 were put in with No. 4. They went through 

 the swinging door at once and No. 4 followed them through in less 

 than two minutes. 



Nos. 5 and 8 got through the swinging door in less than two min- 

 utes when put into the box alone; No. 9 got through in fifteen sec- 

 onds. No. 7 did not get through although he opened the door 

 part way. No. 5 was now placed in an apartment beyond the 

 food in order to make the inducement greater for No. 7 to get out. 

 Although he tried the door repeatedly he did not succeed in get- 

 ting through in ten minutes. No. 5 was now put in with him. 

 No. 5 passed through the door seven times, and No. 7 saw him 

 go through three times. The first time that No. 5 went through 

 the door No. 7 followed him to the extent of pushing the door part 

 way open. The other two times that No. 7 saw No. 5 pass through 

 he made no effort to follow him. 



No. 6 was now put in with No. 7. No. 7 followed him partway 

 through the door but jumped back the moment the door struck 

 him. However, he succeeded in getting through in nineteen min- 

 utes. When put back he went through in fifteen seconds. 



