Wood River times. [volume] (Hailey, Idaho) 1882-1915, 1890-01-15
A COUNTING CHiMpANZEE.



of Experiments
Nature prints an interesting paper read be-
fore the Geological society of London by Pro
fessor George J. Ro,nanes F. Il. s., and fl ON
it the following extracts are made:
"a year or two ago it occurred to me that
might try some psychological experiments
on the intelligence of this animal. The cir
cumstances in which she is placed, however,
did not prove favorable for anything like
systematic instruction. Being constantly ex-
posed to the gaze of u number of people COM
ing and going and having had attention easily
distracted by them, the ape was practically
available for purposes of tuition only during
the early hours of the morning before the
menaSerie is open to the public, and as a
rule, did not find it convenient at that tioa
Therefore, the results which am about to
describe do not, in my opinion, represent
WHAT might fairly have been expected under
more favorable conditions; if the chimpanzee
could have been kept as Il domestic pet for a
few months las kept the cebus kindly lent
Ale for the purposes of psychological observa-
ton by this society, there can be no doubt
that many much more interesting results
might have been obtained. Nevertheless, it
appears to me that even those which have
thus far been obtained are worthy of being
placed on record.
Having enlisted the intelligent co-opera-
zion of the keepers, requested them to ask
the ape repeatedly for one straw, two straws,
or three straws. These she was to pick up
and hand out from among tho litter in her
cage. No constant order was to be observed
in making these requests. but, Whenever she
handed a number not asked for her offer was
refused. while if she gave the proper num-
Der, her offer was accepted, and she received
piece Of fruit as payment. In this way the
ape was eventually taught to associate these
three numbers with their names. Lastly, if
two straws or three straws were demanded,
she was taught to hold one straw or two
straws in her mouth until she had picked up
the remaining straw, and then to hand the
two straws or the three straws together. This
prevented any possible error arising from her
Interpretation of vocal tones--an error which
might well have arisen ii each straw had been
asked for separately
''As soon as the animal understood what
was required and had learned to associate
these three numbers with their names, she
never failed to give the number OF straws
asked for. Her education as then extended
in similar manner from three to four and
from four to five Here, for reasons to be
presently stated. allowed her education to
terminate But. more recently, one of the
keepers has endcavorcd to advance her in.
struction as far rs ten. The result however,
is what might have been anticipated. AL
though she very rarely makes any mistake in
handing out one. two, three, four or five
straws, according to the number asked for,
and, although she is usually accurate in
handing out as many as six or seven, when the
numbers eight nine or ten are named, the re-
c,,lt hapo,par nd fai
to be suggestive of guesswork. 1t is evident,
however, that she understands the words
seven, eight nine aud ten to betoken num-
bers higher than those below Them for if she
is asked for any Of these numbers ii. g.,
above six she always gives some number
that is above six and not more than ten; but
there is no such constant accuracy displayed
in handing out the exact number named as is
the case below six. On the whole, then,
while there is no doubt that this animal can
accurately compute any number OF straws ur
to five, beyond five the accuracy of her com.
putatlon becomes progressively diminished.
at is not necessarily it would be
unreasonable--tO suppose that in this process
of counting the ape employs any system Of
notation. We know from our own experience
that there is counting and counting, i. G., dis
tinguishing between low numbers by directly
approaching the difference between two
quantities of sensuous perception and dis
tinguishing between numbers of any amount
by marking each perception with a separate
sign. The extent to which the former kind of
computation can be carried in the case of man
has been made the subject of a careful re-
search by ProfcHor Preyer, of Jena. His ex.
perimcnts consisted in ascertaiuing the num-
Der of objects such as dots on a piece OF
paper which admit of being simultaneously
estimated with accuracy, and it was found
that the number admits of being largely in
creased by practice until, i'll the case OF some
persons, it may rise to more than twenty.
But, of course, in the case Of brute it is not
to be expected that such a high degree OF
proficiency, even in this non-notatve kind of
counting should he attainable. The utmost
that could here be expected is that brute
should exhibit some s,Eh level of ability US is
presented by young child or by those saw
ages whose powers Of accurate computation
do not appear to extend further than mum
bers which we write as units 1t was in view
OF such considerations that did not attempt
to carry the education of this ape beyond the
number five and the result which has at
tanned subsequent endeavors to teach her
numbers as high as ten is, as previously re-
marked, exactly what might have been an
ticipated 1t may here be added that in the
only records with which | am acquainted of
animals exhibiting any powers Of numerical
computation these powers have not extended
beyond the number five"