The Washington times., 1919-01-05
How Three Little Canals in Each
of Our Ears Keep Us Balanced
and Cause Airmen to Fall by
Making Them Believe They Are
Still Moving in a Certain Direction
When Really They Are Not

When the spirit levels of the semi-cir-
cular canals fail to respond promptly or
are misled into thinking-if it can be
said that organs really think, and some
scientists believe that they do-that the
flying machine has a movement or an
angle different from what it really has that
disaster occurs to the pilot. How is this
centre of our sense of balance misled?
That question is answered by DR.. Lewis
Fisher major and DR.. H. w. Lyman, cap
tain in the Medical Corps of the United
States army. Both Of these scientists
have long been on duty at the great avia-
tiOn camp at Mineola, Long Island, and
have had the best opportunity for obser-
vation possible. They give the results of
these observations in the Journal of the
American Medical Association.
The semi-circular canals are filled with
a liquid called endolymph, and in this
endolymph float a great number of almost
microscopically small hard bodies called
otoliths, literally ear stones. The canals
are close beside, indeed, almost a part of,
the actual centre Of hearing in the ear,
which is a shell-like body called the coch-
lea. The two together are termed the
bOny labyrinth of the ear. There is one,
of course, in each ear. But although so
close together the functions of the semi
circular canals and the cochlea are en-
tirely separate.
The reactions to sound Of the cochlea
are carried through the auditory nerve to
the brain, but the reactions to gravitation
or direction in space Of the body possess
ing It is not carried through this same
nerve by the canals. Science, indeed, has
not yet discovered just how the impress
sions do go from the canals to the brain,
but however transmitted they are trans
-mitted very thoroughly. Vertigo, with its
nausea and other unpleasant symptoms, is
caused by the functioning of these canals
probably more than by any other factor.
1t appears that when the head Is turned
or bent a movement is set up in the liquid
within the semi-circular canals which is
transmitted to the otoliths. 1t is supposed
that these otoliths swinging against the
sides Of the canals touch upon the nerves
there and communicate the sensation of
movement through them to the brain.
When one is whirled about suddenly and
violently or for any. length of time the
movements Of the lymph and otoliths con-
tinue in The ears in the same direction in
which they have been proceeding. When
this happens we have exactly the same
sensation Of movement that we have been
experiencing, although at the time all
movement has ceased. This is why after
a long rock in rocking chair one gets up
and feels as though she were still rocking.
1t also explains why people who have had
long, rough sea voyages for some consid-
cradle time afterward experience the SEN
sation of walking on an unstable earth
All this is due to the fact that the LIQUID
and little stones in the canals have not
yet quieted down.
And in the violent movements which
aviators must experience, especially in
stunt flying" this is doubly true
Here, say Drs. Fisher and
Lyman, is the explanation of
the mysterious falls. The air
pilot is moving at a terrific
speed; fractions of minutes
and even fractions of Sec
II The Three Angles of Movemen
~ Passes. First, the Front
~ Y Third. the Sagittal, OF