x SOME EXPERIMENTAL RESULTS 205 



it worked stiffly, and the box was opened by the lever. 

 This is his record: 



December 6th. I. First tried lever itself, next lifted catch by 

 pushing nose under, but did not understand it. Seized catch by 

 teeth, pushing it down again. Pushed head under catch, raising 

 it, pulled lever, and opened. Time about 50". 



December yth. Morning. 



Did it immediately (keeper's statement). 



Afternoon (own observation). 



1. Raised catch quickly ; did not pull lever at once ; bit at 

 catch ; then pulled. 



2. In interval he has done a " string " trick. 1 In doing that, 

 he tried unsuccessfully putting head under lever. This now puts 

 him off. He gnaws and pulls at both lever and catch for some 

 time, but presently lifts with head and opens. 



December 8th. Morning. Pull bolt added. 

 (Keeper reports) raised catch and pulled bolt together three 

 times rapidly. 



Afternoon (own observation). 



1. Bolt and catch. Knocks up catch, but gets excited, and bites 

 and pulls at right angles at bolt instead of pulling it out. Then 

 bites and struggles all about. 



Catch taken off. Half pulls out bolt, but leaves it hanging, 

 and rampages again. Bolt replaced. Pulls it out up to outer staple 

 and opens. 



2. Does both actions pretty rapidly, lifting catch, then drawing 

 bolt and again lifting catch, which has fallen, and opens. 



3. Keeps on at lever and catch. Pulls bolt half out. Gnaws 

 again. At last opens. Time about 2' 35". 



Subsequent experiments showed that the trick was 

 learnt. 



There was much more of accident in this than in Jack's 

 success, as the detail of the first trial shows. Nevertheless, 

 the otter showed great alertness in taking advantage of an 

 accidental success. 



A second box was then given him, similar to the first, 

 except that the catch had to be depressed instead of raised. 

 Result: 



i. Otter quite baffled all over place ; presently gets chin over 

 catch ; depresses it ; at once puts head under and raises it again. 



1 In this the lever was tied by a string. The experiment failed through 

 difficulties of arrangement. 



