358 ILLINOIS STATE ACADEMY OP SCIENCE 



The query has been raised in some quarters whether 

 the subject in these experiments has not the advantage 

 of bone conduction. I think not, for the following rea- 

 sons: 



(1) The tactual stimuli are so slight that it is incon- 

 ceivable that they can escape being absorbed by the cush- 

 ions of flesh in the palm and in cartilage in the joints in- 

 tervening between the palm and the brain center. 



(2) The subject persistently denies that his exper- 

 ience is auditory. This he could not do if bone conduc- 

 tion were a fact. 



(3) If bone conduction were involved the subject 

 would not be compelled to learn the meaning of the im- 

 pression more than you have to learn the meaning of the 

 impressions you receive when the receiver of your tele- 

 phone is held against your chest. But there has been 

 learning and it was a tedious process. 



I am indebted to Mr. George Crane, Assistant in our 

 department, for indispensable aid in conducting this 

 experiment, and to his brother, John Crane, for having 

 given his time as a subject without academic credit. 



In view of our success with the speaking tube it oc- 

 curred to us to substitute for it an acousticon device such 

 as is used for the aid of the partially deaf. It is well 

 known that if one holds the ear piece of such a device in 

 the hand, one can sense its vibration occasioned by the 

 speaker's voice, against the transmitter at a distance. 

 The question is : "Can a subject learn to interpret these 

 vibrations against the skin in a situation in which hear- 

 ing is out of the question?" 



Through the generosity of the Dictograph Products 

 Corporation of New York City, we were provided at the 

 close of the last academic year, and repeatedly since, 

 with the necessary apparatus. 



It was our expectation to begin experimentation with 

 the present year, following essentially the same method 

 as that which proved successful last year, but with two 

 modifications : 



(1) Stimulation should be applied not to the palm, 

 but directly to the tip of a finger resting lightly against 

 the diaphragm of the receiver. 



