Bismarck daily tribune., 1908-08-28
OUR ERRAT|c SENSES
SoFsie Of the Curious Facts Re-
carded by PhysioIogists.

carded by PhysioIoglsts.
THE PHENOMENA OF SOUND.
Squeais Of Mics and the Lowest Notes
Of en- Organ Are Inaudibie tS Some
Observation-Disclosures Of do Dsli-
cate Senss Of Smell.
| Il you shade the eyes, You weaken
your sense Of hearing. Try IT with q
watch and the result will surprise you.
II you sip glass Of cold water. you
will increase for short time your
| power Of vision. II you I'LL the mouth
with water, you will greatly strength
en- your sense Of smell.
Many similar curious facts about the
senses are told by Psychologists.
( There is a multitude OF sounds made
IN the world every day, for instance,
which we cannot hear. however close
they may be. Every sound must last
certain time in. order to be heard by
the ear. If it is an extremely feeble
sound it must last quite two seconds
or we cannot hear it. But, no matter
how long it lasts, we cannot hear it If
/ 1t is a very low or very high note.
Extremely small animals emit such
high notes that we never hear them.
Some people cannot even hear the
squeal Of mice. The lowest notes of
Ian organ are mere rumbling noises to
most people, and some cannot hear
them at all.
i 1t is by means of the external ear we
! Judge the direction from which sound
comes Stand facing a clock, place
your hands in front OF your ears, with
the palms turned back, close your eyes;
you will then think the clock is behind
i you. es
4 Why can some animals smell more
keenly than others? 1t is question of
i the space within the nose capable Of
smelling. In man this space is very
small-less than one-fourth Of a square
inch. In dogs and most mammals 1t
is very much larger. The porpoise has
no sense of smell. Then comes man,
and also the monkeys, whales and all
kinds of fowl and birds, with very
4 feeble smelling power. When peo-
4 pie talk of vultures scenting dead
bodies they make mistake. Lions,
4 tigers, wolves, etc., can scent them at
long distances, but yultures depend on
their sense Of sight. $ *
Il The sense of smell is exceedingly del
icate. If one ounce of musk were di-
4 yided into 15.Oo0,OO0,0oO parts one of
these infnitesimal parts would be per-
ceptible by the average persons nose.
On the other hand, many people have
no power to smell some substances,
such as mignonette, vanilla, violets and
: prussic acid.
. Taste is curious in the fact that diff.
ferent parts Of the tongue appreciate
. different favors. At the tip we per.
ceive sweet tastes best, at the sides
acid tastes and at the back bitter
: tastes. Substances must be dissolved
, in order to be tasted, and a dry morsel
in dry mouth has no favor. This is
why smokers cannot taste we'll. Their
mouth glands. which manufacture sa-
Iva, are paralyzed by the tobacco.
Very hot or very cold things are scarce
ly tasted at all. If you want to get
} the best flavor from your food it must
{ be at some temperature between so
? and 95 degrees.
Every one knows how easily the
sense of sight is deceived by optical
puzzles. But a curious deception Is
practiced on US all throughout our
} lives, and no one ever perceives it.
: There is blind spot in the eye where
the optic nerve enters. In everything
we look at. therefore. there Is a little
gap where we see nothing. But no one
Is aware of it, because 1t has been the
case since we first opened our eyes.
!, In estimating distance we Judge by
The eye itself cannot Judge distances.
A near hill and q distant mountain
will each form an image of the sama
size on the eye. We know the noun
tain is farther away than the hill be-
cause there are more intervening OBJ.
jects But we can often make an esti.
mate Of distance, in curious way, by
the muscles of the eyeball. In order
to focus q near object we must bulge
the lens, and to focus a distant object
we must flatten the lens. The amount
of muscular labor used in doing this
| gives us an idea of the distance Of the
: object. #
; man seems much thinner in dark
than in light clothing. All black things,
in fact. appear smaller than white
things of the same size. An image re-
mains on the eye for some time after
looking at an object. II the thing Ia
very bright the image remains long
time, and sometimes If you look direct.
ly at the sun you will carry the image
of it around with you for days.
1 Color blind people have defective