Evening star. [volume] (Washington, D.C.) 1854-1972, 1890-06-14

Such little physical phenomena
O. this are experienced by every one and seem
yery puzzling. but how many persons ever
think Of inquiring as to what they signify?
As for the ice cream, when such a big mouth
full Of it il incauti0usly swallowed it produces
chilling effect upon the nerves Of the larynx,
or voice box" and of the pharynx, in the
throat The sensation shoots back to the CEN
ter Of those nerves in the brain; but there it
finds side connection with the great facial
nerve that starts from in front of the ear and
extends its branches over the side Of the face.
One branch OF this facial nerve, extending
across the temple, Is nerve OF sensation,
while the other branches are nerves of motion,
governing chiefly the play Of the mouth. The
PAIN from the chill is sde-tracked along the
nerve branch that traverses the temple and
the feeling is likely to be quite agonizing in
that locality for moment or so, very likely
involving the eyebalI alphabetically. This
feeling of sensation in one nerve when an
other nerve is attacked is what is called reflex
action"
cRAMP IN THE LEG.
Doubtless you have OH occasions walked up
in the night with a fearful pain in the calf Of
your leg and found the muscles drawn up III a
knot. This .'cramp," as it is called. is simply
fatigue. Irritation of any Sort however. may
bring 1t only an electric current, for in
stance, which will render the subject expert
mented upon incapable of extending the limb
affected. A stitch IN the side is the same
sort OF q cramp attacking otheS muscles:
''crick in the neck" is contraction of the
muscles OF the neck owing to cold
slight wrench Of the neck will Outlines
produce most agonlzing sensation of burning,
one or more of the many ligaments that fasten
head aPcurplV unsitiQn HAVING haau
strained for a moment. Every one has felt the
pain in the side that comes from running for a
distance; 1t Is simply a spasm of the muscles of
the diaphragm, from violent and unxccustomed
exercise.
sPEcKs BEFORE THE VISION.
People are often unnecessarily alarmed By
specks floating before their vision, imagining
that blindness threatens. In most cases these
caused by nothing worse than a little in
digestion or cold. slight enlargement of
blood vessels IL the cornea that covers the front
of the eye like watch glass or in the mucous
membrane stretched over the cornea will pro-
duce the symptom. But specks in this
way may sometimes be particles of blood or
OF other foreign substances floating in the
liquid of the eye-in which case disease may
be indicated. When the specks are very NOV
able it Is presumably a trihing congestion of
the superficial membrane. Whisky in mild ex-
cess Is likely to serve as occasion for the phe-
nomenon.
Why Is the roof Of your mouth SO sensitive
that few rubs with your tongue viii render it
unpleasantly sore?
Simply for the reason that beneath the
mucous membrane covering that part are ever
SO many acute nervous papile, only covered
BY coating of epithelial cells. A rub or two
with your tongue will scrape off these pro-
tecting cells and leave the sensitive nerve
extremities bare. Under such conditions they
are sore to the touch. 1t is at the extremity OF
the tongue that such nervous papill@ most
highly developed They perform the function
OF the sense called taste and for its DIR
pose they are distributed all over the inside of
the mouth, palate and upper throat. Different
vIands produce upon these papills varied eff
fects of sensation and by comparison of such
effects the agreeableness of dishes served is
estimated.
FEELING AND SMELLING.
The particularly high development of such
nervous papillR at the ends of the fingers
the result of education of those parts through
countless generations-mak what is termed
the acute sense of touch in the extremities
spoken OF. Contact with object commune
Gates an impression regarding that object to
the brain, and thus it is we feel.
As for smell, it is the most acute BY far of the
hve human senses. Ages ago it was vastly
more keen in man than is now the case; but it
has lost by disuse. Take ounce of musk
most powerful of scents-and leave il where
the atmosphere Is still. open on a table, for a
year AZ tue emu OF ludt tlibe. having IOr full
twelvemOnth rendered odorous the whole air
in Its neighborhoOd, the most delicate scales
cannot detect that 1T has lost q particle in
weight Yet the smell has been infinitely dis
trIbuted, microscopic portions of the musk
floating OF and exciting impressions upon the
nerve papillR under the delicate lining of the
nasal passages; for this is what ling means
The sense has grown almost documentary in
human beings, through want of necessity for
Its use under civilized conditions; but it is
highly DrOlablp that the "a m haH ito
as well developed as the sharpest-nosed beasts
Two hundred thousands years ago the condi-
tons Of life were different
HOW ONE HEARS
Strangers visiting Washington have been
heard to remark that it seemed to them more
deaf people were to be found here than they
had ever met in any other city. 1t is astonish-
ing how few persons actually of defective
hearing have any notion of the structure of the
ear. The membrane stretched across the in
terror passage and called the drum" merely
serves TO catch and transmit the vibrations.
like the diaphram in telephone. In contact
with this drum is the extremity of little bone
which little bone is connected with second
little bone, while the second bone is hitched on
TO third little bone, all working together like
levers, IN order TO increase the power of the
vibrations acting upon the drum. The inner
end OF the third little bone comes into contact
with second drum, which Is the wall of a
receptacle filed with liquid. sound from
without causes a vibration of the drum: the
vibration Is communicated through the three
little bones and causes d series of pressures
upon the wall of the hquid-illed receptacle:
nlaments OF the auditory nerve floating in the
liquid are agitated by the vibration thus COM
municated; the auditory nerve conveys the i'm
preston to the BRAIN and thus it il we hear
To our notion all creation is filed with sounds
whereas in reality what We conceive to be
sounds are but vibrations of the air and pre-
sumably the universe is in fact one illimitable
silence.
WHAT Is INFANT BY SIGHT IS THIS:
Rays of light reflected from an object enter
lhe round hole in the iris of the eye, called the
pupil, and strike the nerve screen that lines the
eyeball, called the .'retina." The rays carry
with them a picture OF the object they come
from. and this picture is photographed upon
the retlna by the action of the ocular pur-
pie chemical resembling in its manner of
working the preparation used for a similar pur-
pose by the professional photographer. At the
back OF the eye the optic nerve enters spread
ing out into the retina, which for ms the screen
for the reception Of the photog raph, and by the
optic nerve the impression of the picture ia
conveyed to the brain and the object is seen"
As an illustration of nervous action il ia IN
teresting TO observe the fact that one has only
TO TX his attention upon any part OF his anat-
Omy for a brief space in order to make that
portion very painful. Concentrate your mind
upon your little toe for two minutes and at the