Evening star. [volume] (Washington, D.C.) 1854-1972, 1909-07-29
the Sensation OF NEARNESS
PROXIMITY OF OBJECTS TOLD
WITHOUT SIGHT OR TOUCH.
Investigation Into the Matter OF
Standardization and the Refec-
ton Of Radiant Heat.

From the Literary Digest.
Those who have felt, in dark room. a
sensation Of the proximity Of some article
OF furniture or Of the walls. and who
think that this sensation is not merely
imaginary, will be interested in letter
written 10 London Nature by DIR. Charles
III. Melland of Manchester, England In
which he describes some experiments on
the SUBJECT. DR.. Melland believes that this
feeling OF the nearness of objects In the
dark by which blind persons often assert
that they are correctly guided. Is the re-
suit of differences. partly from sound-re-
Election and partly from the reflection OF
radiant heat. the latter being perceived
especially by the face. Says DIR. Melland:
working as | was frequently until &,
late hour in the pathological laboratory
Of a London hospital which opened on
the entrance hall. had. in order to reach
my room, to cross the hall Obi1quely anu
enter the corridor by a wide door, some
six feet wide, with folding glass doors.
which were as rule, fastened back. The
hall and corridor were unlighted. l usual
" walked well out into the nall from
the door of the pathological laboratory,
turned to the right when thought was
opposite the door opening into the cor
ridor, and then walked straight Forward
between the doors. | found, good deal
10 my surprise, that though In the dark,
even though | shut my eyes, couio Juoee
as walked through. very accurately, 10
which of the two doors ] was nearest. l
made a large number of observations and
the constant result was sufficient, thlhk'
to preclude any idea of mere coincidence.
! found / could even form trustworthy
estimate If l was only few inches
nearer one side than the other' ano'
further, If I gradually moved toward one
or other side. when | got WITHIN lew
inches of the door L felt that was sei-
ting very close TO It,
THE way i'm which ] felt this is difficult
to describe. but the sensation of near
ness was situated I'm my race, on my
forehead and cheeks. and seemed TO De
particularly keen on turning my cheek In
the direction of the surface that l was
approaching. The conclusion that came
to was that there were two d1nerent pro-
ceSses involved. in the first case I'd the
nearness OF solid body was made evil
dent by difference in the reflection OF
resonance of my footsteps as l walked
and i'm (.) the differences in the reflection
of the heat of the face from a surface
at varying distances were the cause OF o,
the sense of nearness or fairness. 1t will
be seen that had arrived at almost pre-
cisely the explanation which DR.. Mcken-
drick puts forward as the explanation or
the power of the blind to recognize their
relation to externals.
"uO To test nv theory Of sound ref1ec-
ton tried the effect of walking In stock
inged feet. and found that 1t senslbiy d.
minished my power of recognizing my
position: this is. of course quite anaio
Rous to the difficulty. which DR.. Mcken-
drick describes. experienced by the pima
when there is snow upon the ground.
Minute Sound Changes.
Since these first observations were
made by Dr. Melland he has. he tells us.
noted other occasions which minute
fur
formation Any one. he says. may read
lily prove for himself in walking in the
dark or with the eyes shut along a CORR
dor with doors, some open and others
closed, how easy ii is to recognize when
one comes opposite one OF the open doors.
owing to difference in resonance. Again,
he has more than once noticed when rid
ing on top of a tram car that he has been
sensible of another passenger sitting
quietly down on the seat behind. not
through any sound that he has made, but
by his cutting OF portion of the general
roar of trafhc.
He goes on:
1T l.; the finer sound indications of
this type, to which we customarily pay
little heed since our eyes yield us more
rapid and more complete information,
that convey so much information to the
blind, whose ears, If not more keen. are
more intent. and the blind mans stick
undoubtedly serves not only to feel his
way WILL Out DS ltS tap " supply a
source of sound the resonance of which
may be noted. There is still much haz-
ness. even among those who have to
do with the management OF the blind, as
to their psychology, and one superin-
tendent of a blind asylum with whom 1
am acquainted. INDUCING in that mys-
ticism which at the present day is so
fond OF explaining phenomena. of which
by experiment one may learn something,
by theories Of which we know nothing,
would drag in that blest word telepathy'
to explain the blind mans knowledge of
the surrounding objects.
Perception Of Heat.
''2) The second principle involved. viz,
the reflection of the heat of the face
from adjacent surfaces, is not SO easily
verifable. / feel fairly confident, how
ever. that accurate observations with a
delicate surface thermometer would show
that the cheek was receiving a certain
amount OF reflected heat as 1t was APP
preached near to a solid object That
the skin of the cheek is peculiarly sensi-
tive to the degree of temperature will
be readily admitted by any one who has
seen a laundress testing the proper heat
of her iron by holding it to her face
Further. the repetition of the expert
ment with the use of mask which
would minimize the sensitiveness of the
skin to changes of temperature, has
struck me as likely to give conclusive
results. and l am particularly interested
70 ind this supposition supported by Dr.
Mckendricks statement that the blind
do not so readily avoid an obstacle if the