422 
ANIMAL INTELLIGENCE. 
served that the door is opened by the hand grasping the 
handle and moving the latch. Next she must reason, by 
6 the logic of feelings ? — If a hand can do it, why not a 
paw ? Then, strongly moved by this idea, she makes the 
first trial. The steps which follow have not been ob- 
served, so we cannot certainly say whether she learns by a 
succession of trials that depression of the thumb-piece con- 
stitutes the essential part of the process, or, perhaps more 
probably, that her initial observations supplied her with 
the idea of clicking the thumb-piece. But, however this 
may be, it is certain that the pushing with the hind feet 
after depressing the latch must be due to adaptive reasoning 
unassisted by observation ; and only by the concerted 
action of all her limbs in the performance of a highly com- 
plex and most unnatural movement is her final purpose 
attained. 
Again, several very similar cases are communicated to 
me of cats spontaneously, or without tuition, learning 
to knock knockers and ring bells. Of course in both 
cases the animals must have observed the use to which 
knockers and bells are put, and when desiring a door to be 
opened, employ these signals for the purpose. It betokens 
no small amount of observation and reasoning in a cat to 
jump at a knocker with the expectation of thereby .sum- 
moning a servant to open the door — especially as in some 
of the cases the jump is not a random jump at the 
knocker, but a deliberate and complex action, having for 
its purposes the raising and letting fall of the knocker. 
For instance, Mr. Belshaw, writing to 6 Nature ’ (vol. xix., 
p. 659), says : — 
I was sitting in one of the rooms, the first evening there, and 
hearing a loud knock at the front door was told not to heed it, 
as it was only this kitten asking admittance. Not believing it, 
I watched for myself, and very soon saw the kitten jump on to 
the door, hang on by one leg, and put the other fore-paw right 
through the knocker and rap twice. 
In such cases the action closely resembles that of 
opening thumb-latches, but clearly is performed with 
the purpose of summoning some one else to open the 
door. Wonderful, however, as these cases of summoning 
