revealed by an attempt to train it to do some particular thing, in
a manner that the trainer elects. Usually about five lessons,
carefully observed, will afford a good index of the pupil's mental
capabilities. Some chimpanzees are too nervous to be taught, some
are too obstinate, and others are too impatient of restraint. Some
orang-utans are hopelessly indifferent to the business in hand,
and refuse to become interested in it. I think that no orang is
too dull to learn to sit at a table, and eat with the utensils
that are usually considered sacred to man's use, but the majority
of them care only for the food, and take no interest in the
function. On the other hand, the average chimpanzee is as restless
as a newly-caught eel, and its mind is dominated by a desire to
climb far beyond the reach of restraining hands, and to do almost
anything save that which is particularly desired.

Among the twenty or more orangs which up to 1922 have been
exhibited in the Zoological Park, two stand out with special
prominence, by reason of their unusual mental qualities. They
differed widely from each other. One was a born actor and
imitator, who loved human partnership in his daily affairs. The
other was an original thinker and reasoner, with a genius for
invention, and at all times impatient of training and restraint.
The first was named Rajah, the latter was called Dohong.

Rajah was a male orang, and about four years of age when received
by us. His high and broad forehead, large eyes and general breadth
of cranium and jaw marked him at once as belonging to the higher
caste of orangs. Dealers and experts have no difficulty in
recognizing at one glance an orang that has a good brain and good
general physique from those which are thin-headed, narrow-jawed,