(. Presented before the Texas Academy of Science June 15 , 1896.) 
AURAL PERCEPTION BY THE BLIND. 
A PRELIMINARY REPORT. 
BY DRS. S. E. MEZES AND H. L. HILGARTNER. 
Owing to the iarge place occupied by ■visual perception in our normal 
experience of outer objects, it is exceedingly difficult to furnish satis- 
factory descriptions of the rare and overlaid instances of perception by 
the other senses. It is to those deficient in one or more of the senses 
that we must turn for our most valuable evidence. In the blind, no 
doubt, touch takes the place of sight as the intellectual sense par ex- 
cellence ; but the limitation of the information it gives them to objects in 
contact with the body, coupled with the reach of their perceptual horizon 
far beyond the body, makes it plain that they must depend on the lower 
senses for a large part of their perceptions. In so far as^an be described, 
the general theory of perception ^y ao nsp pp^«p+i™-> be the 1 
gainer; indeed, to establish the bare existence of, say, aural perception of 
distant objects, is to assist materially in the solution of the vexed ques- 
tion of the third dimension in vision, for the ear is less sensitive to depth 
than the eye — it furnishes no sensations auxiliary to sound that vary 
with depth. 
Authorities on the psychology of the blind agree that they have a 
somewhat detailed sense of their surroundings. They know whether 
they are on a plain, on a mountain top, or in a valley, whether they are 
out of doors or indoors, in a large or a small room, whether it is bare 
or furnished, and, with more individual variations, the kind of furniture 
therein. Such "perceptions” are, to be sure, decidedly vague, but they 
are marked unmistakably by the sense of exteriority, insistence and sen- 
sational vividness. Naturally, near objects are most clearly perceived — 
the fences on either side the road, houses and stores along the streets, 
persons, lamp posts or other obstacles in their way, especially when the 
. obstacle stands more than shoulder-high; then the blind can often per- 
ceive the nature of the obstacle. It was with a view to determining 
which of the lower senses is the informant, and, if more than one, what. 
