182 Animal Intelligence 
way that it could be easily reached by the monkey’s arm 
through the wire netting. 
QQ (a) was of the same general plan. By turning a 
handle through 270° food could be obtained. 
QQ (b) was like QQ (a) except that 2} full revolutions 
of the handle in one direction were necessary to cause the 
food to drop down. 
QQ (c) was a chute apparatus so arranged as to work when 
a nail was pulled out of a hole. 
QQ (d) was arranged to Wark at a sharp pull upon a brass 
ring hanging to it. + 
QQ (e) was arranged to work when a hook was unhooked. 
QQ (f) was arranged to work when a loop at the end of a 
string was pulled off from a nail. 
QQ (ff) was QQ (f) with a stiff wire loop instead of a loop 
of string. 
EXPERIMENTS ON THE ABILITIES OF THE MONKEYS 
TO LEARN WITHOUT TUITION 
I will describe a few of the experiments with No. 1 as 
samples and then present the rest in the form of a table. 
No. 1 was tried first in BB (O at back) on January 17, 1900, 
being put inside. He opened the box by pulling up the 
string just above the bolt. His times were .o5, 1.38, 6.00, 
I.00, .10, .05, .05. He was not easily handled at this time, 
so I changed the experiment to the form adopted in future 
experiments. I put the food inside and left the animal to 
open the door from the outside. He pulled the string up 
within 10 seconds each time out of to trials. 
I then tried him in MM (bolt). He failed in 15. I then 
(January 18th) tried him in CC (single bar outside.) He 
got in in 36.00 minutes; he did not succeed a second time 
