Idaho semi-weekly world. [volume] (Idaho City, Idaho Territory) 1875-1908, 1891-04-17
ALMOST THE PHILOSOPHERS SCALES


Remarkable Instruments Used by the Mod
ern Psychologists.
"Robin Goodfellow' might boast that
he could put girdle round the earth in
forty minutes but modern psychologists
are learning to accomplish far more re-
markabe things In the world of mat
ter they are of little worth, but they have
gotten hold Of the minds leading strings,
and have contrived 50 ingeniously that
"all thoughts, all passions, all delights
have become reducible to mathematical
formula. Not only have they learned
to express the poets dream in prosaic
millimetres. and affairs of the heart in
cold, unfeeling decimals, but the inten-
sity of stroke of lumbago and the rate
of speed of dyspeptic twinge they now
calculate with numerical exactness.
1t is an actual fact that psychologists
will soon have as complete insight into
the operations of the mind as have ply
sicians into the functions of the body
The University of Pennsylvania is the
pioneer in introducing the mind measur-
ing system into America Professor Cat
tell brought with him from Germany
some quite remarkable instruments,
principally of his own invention, which
are employed in demonstrating his psy-
Geological lectures. They perform tasks
which materialists have secuted as inn
possibilities, and strongly tend to prove
that psychology, despite all that has been
said to the contrary, is an exact science.
One of these Instruments will calcu-
late to a nicely the travelling speed of an
impression. chronoscope and vol
taic battery are the principal agents in
the solution of this intricate problem.
By their means registration is made of
the exact time that elapses between the
occurrence of an act and the sign given
by the subject operated upon that he has
perceived the act BY process of sub
traction the time is discovered which
passes between the moment at which
the impression reaches consciousness
and the moment when the subject knows
he perceives In this manner a mans
rapidity of perception-hi ability to see,
taste, smell, hear or feel-may be accu-
rately determined.
For the measurement of sound the sub
ject forms a circuit by applying his hands
to the two poles of the battery. On hear
ing specified noise he instantly breaks
the circuit Immediately the hand OF
the chronoscope stops short, indicating
in thousandths of a second the time that
has elapsed between the occurrence OF
the sound and the breaking of the cir
cult. On this basis mans perceptive
power is calculated
BY analogous means the comparative
swiftness of sight is measured. PROBES
sor Cattell has ascertained, for instance
that one-tenth of a second suffices TO
him to perceive a color, oce-eighth of I
second is necessary for the perception o
a letter, and one-seventh of n second TO
word
The strength Of a persons memory
determined by a complicated machin
which presents to the eye at intervals c
a second flashes of light of varying dc
grees of intensity, The more subtle is
mans power of recognition the NOR
readily he distinguishes one light spc
from another, and the longer he retain
his impressions. In this way the mind
concentration and retentivencss al
measured in fractions of a second
By means of the gravity chronometC
the comparative ease or difficulty wit
which letters or words may be perceive
is demonstrated In a sliding scree
moved by electricity a slit five inch,
wide is inserted behind which an objet
is exposed to view for an infinitessim
space of time.
In series of experiments with Il
letters of the alphabet the time of expo
ure was one-thousaudth of a secon
That of 270 trials w was seen PAL time
while L appeared seen but 90 times
other capital letters z. Nj, ID and
ranked next in succession after in Il
quickness with which they were pc
ceived, while V, F, U and were o
served only with great difficulty.
the small letters I'd" is the most east
recognized, and IS" least easily, the fo
mer being perceived three times as off
as the latter.
If the several colors are exposed
view in like manner for fraction of
second orange and yellow will be mo
clearly perceived. Blue, red and gre,
follow in the order named, violet beiI
the least easily recognized and requiriI
two or three times as long exposure
the bright colors This device serves
measure the range or completely of t
mind. Philadelphia Record.
Typical English Report.
If | were asked for an epitome