Evening star. [volume] (Washington, D.C.) 1854-1972, 1903-09-25
FRAUDS ON TIE SENSES
DECEPTIoNs OF SIGHT MATCHED
BY THOSE OF TOUCH AND SOUND.
The aristotle Pea" Illusion-Mistake
That Persons Make in the Mat
ter Of Weights.

From the Boston Herald.
1t is wonderful how readily we are
cheated by those five senses of ours, upon
which we rely with such confidence. The
ease with which our eyes deceive us is no.
torious. and. If seeing is believing" We
are surely victims of a confidence mis-
placed. But, leaving optical Illusions aside,
there are receptions of the other senses
taste, hearing, touch and smell-which are
not less interesting and, comparatively
speaking, unknown.
One illusion of touch that is compare
lively we'll known is the pea of Aristotle"
so called because that ancient sage and
philosopher is supposed to have been first
to make note of the phenomenon.
If you roll pea "a pellet of bread will
do as WELD on a table between the ends of
the forefinger and middle finger OF your
right hand it will feel Of course, like one
pea. But IL you cross the two fingers and
do the same thing it will feel ike two peas,
and the Illusion will be so perfect that you
can hardly realize that there is not a sec
ond pea. The phenomenon affords a most
interesting illustration of the ease with
judgment
But the senses are the gayest of deceiv-
ers. and the things they tell not to
be relied upon implicitly by any means.
Oil derived from the peppermint plant II
you rub 1t on your forehead or on any other
part of your body it produces feeling of
icy GOODNESS.
cul1ar property of the substance. which
stimulates the little nerves of cold sensa-
ton beneath the skin. All over the body
are distributed nerves of cold and nerves
of heat. the former can only feel GOODNESS
and the latter can only feel warmth The
menthol is not cold but it feels so for the
reason above mentioned
Flash in the Dark
Each set of nerves has its own particular
Kind of sensation. If you shut your eyelids
in dark room quickly and tightly. you
Will perceive something like flash of light,
which is due to irritation of the optic nerve
Any kind Of shock to the auditory nerve
will produce loud sound
1rritate. no matter by what means any
or the nerves, and it responds by conveying
It's own peculiar sense impression to the
brain. Thus 1t Is that one is able to taste
electricity when the poles of battery are
applied to the tongue. The papillae on the
surface of the tongue each of which rep
resents tiny nerve ending. are stimulated
and an Illusion of favor results.
You may try an odd experiment in re-
gard to taste sensations by placing stimuli
taEeously on different parts of the tongue
two substances of markedly different fla
Vors-say, sugar and salt You will not
taste tnem DOLn at the same time, nor as
a mixture, but they will alternate back and
forth; you will taste first the sweet and
then the salt, and the sweet again. and
then the salt as sense perception jumps
back and forth between the two. 1t is
really very curious and illustrates the fact
that one cannot possibly taste more than
one thing at any given moment.
This however, is not exactly deception
of sense but merely an interesting physi-
olCgical experiment. More properly to be
described illusion of taste is the
peculiar effect which hot soup sometimes
has when one takes it into the mouth with
out due caution. Once in a while under
such circumstances, it causes, strangely
enough, a sensation of cold, evidently be-
cause it irritates the little nerve endings
of cold on the surface of the tongue.
Test of Smell
Just as it is impossible to perceive two
tastes at once likewise you cannot dis
tinguish two different smells at the same
instant. You may test this by making two
cornucopias Of letter paper and placing
the large end of each of them over some
strong-scented substance-say, peppermint
and weak solution of ammonia, contained
in couple of wineglasses. Then put the
small ends of the cornucopias into your
nostr1ls and notice the effect. You will
smell not both together, but the ammonia
and peppermint alternately. fuctuating
back and forth from to the other
Now for something in different line:
Plunge your right hand into a Jar of Wate
that is just a bit too hot to be bearable
You will withdraw it Immediately and say
that you cannot stand it. But it, thereupon
you put your left hand into another vessel
containing moderately warm water and
gradually raise the temperature of the
latter. you will find that you can endure it
10 or 10 degrees higher than the first water
you tried. 1t is natural enough that this
should be SO; but now place your right
hand again in jar No. 1 the temperature of
which has not altered by fraction of
degree). and the water which at first was
uncomfortable will feel cool The same hand
that found the water unbearably hot in the
first instance experiences a sensation of
GOODNESS at the same point of the thermom-
eter five minutes later
The same idea may lie illustrated in an
even more striking wa: by using three
1ars-the first containing hot water. the
second cold water and the third lukeWarm
water. If you put your left hand into the
lukeWarm water and your right hand into
the not water, the tepid water will feel
cold. transfer your right hand to the cold
water and the tepid water will feel hot In
other words, water at a given temperature
feels hot or cold according to circum
stances.
one of the simplest and most striking of
Illusions OF feeling has to do with the rela-
i've weight of things. Two objects of the
same shape and color. but of different
sizes Zone being, say. eight or ten times as
big as the other), weigh exactly the same
number of ounces. When asked to Judge
which is the heavier ninety-nine persons
out of "A hundred will say that the little
one Is superior in point of avordupois.