SOME RESULTS OF EXPERIMENT 143 
near the crook. At length he seized the crook itself, and with 
a wrench broke it off. A man who was passing, and who had 
paused for a couple of minutes to watch the proceedings, said, 
“Clever dog that, sir; he knows where the hitch do lie.” The 
remark was the characteristic outcome of two minutes’ chance 
observation. During the half hour or more during which I 
had watched the dog he had tried nearly every possible way of 
holding and tugging at the stick. Such is the mode of 
behaviour based on intelligence—continued trial and failure, 
until a happy effect is reached, not by methodically planning, 
but by chance. 
Two of my friends criticized these results, and said that 
they only showed how stupid my dog was. Their dogs would 
have acted very differently. I suggested that the question 
could easily be put to the test of experiment. The behaviour 
of the dog was in each cage—the one a very intelligent York- 
shire terrier, the other an English terrier—similar to that 
above described. The owner of the latter was somewhat 
. annoyed, used forcible language, and told the dog that he 
could do it perfectly well if he tried. 
In experimenting with my fox terrier on the method 
adopted in seizing and carrying differently balanced objects, 
I used (1) a straight stick, the centre of gravity of which was 
at the middle; (2) a Kaffir knob-kerrie, the centre of gravity 
of which was about six inches from the knob ; (3) a light 
geological hammer; and (4) a heavier hammer. In the last, 
the centre of balance was close to the hammer head. The net 
result of the observations was that the best place for seizing 
and holding the object was hit upon in each case after indefinite 
trials ; that after three or four days’ continuous experience with 
one (say the knob-kerrie), another (say the stick) was at first 
seized nearer one end, showing the influence of the more recent 
association ; and that there was little indication of the dog’s 
seizing any one of the four at once in the right place, that is 
to say, the point of seizure was not clearly differentiated in 
accordance with the look of the object. I tied a piece of 
string, in later trials, round the centre of balance, but this, at 
