The Republican. [volume] (Oakland, Md.) 1877-current, 1893-08-03
SENSE OF TOUCH.
How 1t Varies In Different Parts OF the
Human Body.

1 human htOuys
If there is any subject that people in
general think they are specially ia
miliar with that subject is their own
| sense of touch or skin-feeling. Yet how
| few will not be surprised to learn that
the points of pair of compasses held
| two and three-fifths inches apart
| against the middle of ones own back
| feel like but one point? If opened out
to two and half inches they feel like
two. This was discovered by Weber in
series of experiments to which Mr..
Herbert Spencer has lately called at
| tentiop.
Weber found the tips Of the fore
| fingers could feel the two points when
they were one-twelfth of an inch apart,
but not when closer together. Between
this fine sensitiveness and the coarse
sensitiveness of the middle of the back
all the outer parts of the body vary.
For instance, the inner surface OF
the second joints of the forehnger can
distinguish the two compass points
one-sixth of an inch apart. The inner
most points have less sensitiveness of
this sort, but rank in it equal with the
| tip of the nose The end of the toe, the
| palm of the hand and the cheek have
alike one-fifth of the perceptivcness of
| the tip of the forefinger, and the lower
| part of the forehead has one-haf that
| of the cheek.
The back of the hand and the crown
of the head are nearly alike in having
| fourteen times less sensitiveness Of
this sort than the tip of the forefnger.
| The thigh has less near the knee and
the points of the compasses must be an
inch and one-half apart before the
breast ceases to feel them as one.
Mr.. Spencer accounts for these diff
ferences on the ground OF the greater
practice of some parts of the body in
feeling various objects. For instance.
the finger-tips are educated in the
matter, and their qualities transmitted
by inheritance to successive genera
tions, The tongue, always feeling the
teeth, and often feeling particles of
food, is still better educated. Its tip
can distinguish between compass
points one-twenty-fourth of an inch
apart, and is the most sensitive mem.
Der of the body.
MT. cpeHcer IneOry dSrccS WIN
some well-known facts. For example,
he showed what was pretty well known
long before he was born, that the
finger-tips of the blind are more sensi-
tive than those of persons who can sec,
and who therefore do not practice
their sense of touch so much. He also
found that skilled type-setters were
more sensitive than the blind on whom
he experimental, for the type-setters
could distinguish both compass points
when one-seventeenth of an inch apart.
1t may be suggested that many facts
could be adduced to show that parts of
the body do not become more but less
sensitive by continual touching OF
things. The fingers of seamstress
are often 'calloused" by needle pricks
or pressures, and yet she is always as
much seeking to avoid the pricking as
the type-setter is to seize but one type.
But in such scientific matters theo-'
ries are plenty and easily made. The
facts themselves are the interesting
things, as are all pieces of novel infor-
nation about the wonderful human
| body.-Youth's Companion.