The Princeton union., 1879-04-02

Feats Of a Talented Canine Which K1eaU
HoaU to Eetract Square Root.
Edinburgh Review.
The we'll known spectroscopist and astron-
omer, DR.. Huggins, had a four-footed friend
dwelling with him for many years as regu-
lar member of his household, who was
mastiff of very noble proportions by descent,
and who bore the great name of Kepler.
This dog possessed many rare gifts
which had secured for him the admira-
ton and regard of large num-
Der of scientific acquaintance, and among
them there was one which he was always
ready to exercise for the entertainment of
visitors. At the close of luncheon or din
ner, Kepler used to march gravely and Sc
dately into the room and set himself down
at his masters feet. DIR. Higgins then pro-
pounded to him series of arithmetical
questions, which the dog invariably solved
without mistake. Square roots were OK
tracted off hand with the utmost readiness
and promptness. If asked what was the
square root of 8, Kepler wonld reply by
three barks; or, if the question were the
square of 16, by four. The various ques-
tions followed, in which much more compli-
Gated processes were involved for in
stance, as ''add to 8, divide the sum by 3,
and multiply by 30 To such a ques-
ton as that Kepler gave more consideration,
and sometimes hesitated in making up his
mind as to where his barks ought finally to
stop. Still, in the end, his decision was al
ways right. The reward for each correct
answer was piece of cake, which was held
before him during the exercise; but until the
solution was arrived at Kepler never moved
his eye from his masters face. The i'll
stant the last bark was given he transferred
his attention to the cake. DR.. Huggins was
perfectly unconscious of suggesting the
proper answer to the dog, but it is beyond
all question that he did SO. The wonderful
fact is that Kepler had acquired the habit of
reading in his masters eye or coun-
tenance some indication that was not
known to DR.. Higgins himself.
The case was one of the class which is
distinguished by psychologists as that of ex.
pectant attention. DR.. Huggins was himself
engaged in working out mentally the various
stages of his arithmetical processes as he
propounded the numbers to Kepler, and, be-
ing therefore aware of what the answers
should be, expected the dog to cease barking
when that number was reached, and that ex
pectation suggested to his own brain the un.
conscious signal which was caught by the
quick eye of the dog. The instance is strict
ly analogous to the we'll case in which
a button, suspended from thread and hello
by finger near to the rim of glass, strikes
the hour of the day as it swings. and ther
stops-that is, provided the person who holds
the button himself knows the hour! The OK
PLANTATION of this occurrence is that the hanG
which holds the button trembles in conse-
quence of it's constrained position, and il
that way sets the button swinging, and al
the attention of the experimenter is fxe6
!: upon the oscillation, in the expectation thai
definite number of strokes upon the glass
will occur, his own brain convolutions take
|. care that the movements of the finger shal
, be in accordance with that expectation
The mathematical training of poor Keplel
has, unfortunately, come to an untimel,
! end. The interesting arithmetician died O
an attack of typhus fever, to the great
sorrow of his large circle of friends, at tn,
, beginning of last year, and he now sleep,
under the shadow of the telescopes at Tuls,
!, hill. The memory of his high attainment.
and of the distinguished success with which
, he upheld the reputation of his name, how
ever, remains. His most intimate friend
{ also enjoy the consolation of an excellen
portrait of his thoughtful face, lit up will
the exact expression which it bore when h.
was engaged with his arithmetical prob
i, ably.
A,, r.