AURAL PERCEPTION EY THE BLIND MEZES AND IIILGARTNER. 
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The first column was obtained by dividing the number of times a 
subject detected a board or other obstacle (by stopping some distance in 
front of it) pins the number of times he walked 30 feet when there was 
no board, by his total number of trials. More trials were made with 
some subjects than with others, the number varying from six to seven- 
teen. The closing of the Institute for the summer prevented further 
experimentation. The figures of the second column are the average dis- 
tance of hoards, trees, or other obstacles, from subjects when they 
stopped. The other columns explain themselves. 
One conclusion can he safely drawn. In most of the blind the ear 
plays much the largest part in the perception of objects out of contact. 
Comparing W. S. with our blind subjects, shows how much less sensitive 
he is, and suggests that experiments on the seeing are not conclusive. 
In looking for evidence of “facial perception” among our subjects, we 
find hints rather than trustworthy evidence. L. R/s case we regard as 
too doubtful to be of am^ value. He is very young, has been blind four 
years only, discerned hoard at two feet with ears open, as contrasted with 
five feet with ears stopped, and during the latter trials he seemed to he 
guessing. A. G/s case is more satisfactory. It indicates that though the 
ears he stopped the blind may perceive an object that radiates much heat, 
or intercepts much heat or wind. It may be that this source of informa- 
tion, at the command, apparently, of some of our subjects, is the chief 
reliance of a few of the blind. It would he interesting to discover how 
much more sensitive they are in this direction than the seeing, and es- 
pecially interesting to experiment on subjects at once blind and deaf. 
While N. A/s evidence of what “facial perception” is, is not so clear, her 
frequent failures mean little in view of her low record with open ears. 
Among our subjects, the record of the girls is much lower than that 
of the boys. Our cases are too few to warrant generalization, hut it is 
worth while stating that while the former walk along the paths in 
groups, composed generally in part of seeing members, the latter walk 
alone and cross lots. 
We had hoped that our figures would show the effect of experience on 
the keenness of aural perception, but nothing definite appears. 
