1825.] 
moiety of man, from the diaphragm up- 
wards, may be regarded as “an auto- 
matic clarionet ;” every part of which, 
braced by proper attitude and manage- 
ment, may be brought into some de- 
gree of unison with the larynx itself, 
and made to respond to the impulses 
of that organ, so as to strengthen and 
modify the intonation. 
That indefatigable and accurate ob- 
server of the phenomena of hearing and 
of touch, was first led to this hypothe- 
sis, by observing the change that took 
place in his voice during the act of 
bathing, whenever the chest was com- 
pletely submersed. This circumstance 
led him to try several experiments, and, 
among the rest, frequently to apply his 
fingers (the sense of touch being, in his 
instance, remarkably delicate) to the ribs 
and different parts of his body, during 
the act of speaking; when the vibra- 
tions of the chest were found so exactly 
to coincide with the different actions of 
the voice, as to leave no doubt of the 
fact. 
These experiments I liave tried again, 
in my own instance; and have added 
many others, with the most satisfactory 
effect. 
With respect to the bath, indeed, I 
at first suspected some fallacy; for it 
is to be considered, that in the act of 
speaking, under ordinary circumstances, 
the vibrations (which are necessarily 
propagated, not in a horizontal circle 
only, but in all directions, through a 
given sphere) are transmitted through 
an aérial medium below, as well as 
above; while, in the bath, when the 
chest and shoulders are submersed, 
nearly one-half of the aerial pulses, sup- 
posing them merely to proceed from the 
mouth and larynx, must yet be trans- 
mitted through an aqueous medium. 
It would, therefore, necessarily ensue, 
that some alteration of the character 
of the vocal sound would be produced 
from this alteration: as the sounds of 
musical instruments, in effect, become 
modified, by their being played in a 
boat upon the water. But though this 
circumstance would account for some 
part of the change, I found it would not 
account for the whole. The process 
by which [ attained to this conclusion 
was by repeating the experiment in a 
bath of very favourable structure (be- 
ing, in fact, one of the great boilers of a 
dye-house in Kendal), in which, when 
it was properly filled, T could remain 
with the chest and shoulders completely 
The Anatomy of Speech. 
491 
submersed ; while,- the chin being pro- 
jected over the edge, the oral impulse 
was completely transmitted through the 
common atmospheric medium. The 
result was—that, notwithstanding this 
precaution, the alteration of the tone 
was still so conspicuous as to leave no 
doubt of its originating in the suppres- 
sion, or modification of the vibrations of 
part of the resounding or vibratory sur- 
face, by the pressure of the water from 
without.* 
But the sonorous vibrations of the 
upper part of the trunk may be further 
ascertained, by a very easy and simple 
experiment. Let any person, in the 
act of reading or speaking, place himself 
in an armed chair of tolerably fayour- 
able structure—a slight mahogany chair 
for example, that is neatly and firmly 
compacted, or any light article of that 
description, and the back and arms of 
which are not encumbered with pads or 
cushions, which might impede the vi- 
bration. Upon a chair thus constructed, 
let him dispose his limbs and body in 
such a way, that any part of the trunk 
above the diaphragm (spine, ribs, or 
breast) shall be in contact with any 
part of the back or arms of the chair ; 
and then, while he is so situated, and 
reading or pronouncing with tolerable 
energy, let any other person lay a hand 
upon the chair-back; and, in the com- 
municated vibrations of the frame of 
the chair, the result will be obvious 
and conclusive. Every change of vocal 
effort will be so distinctly felt, that one 
might be tempted to exclaim, with a 
certain deaf lady, who was taught to 
play upon the piano-forte, “I feel I 
hear.” But if, on the contrary, it be 
the arm only, or any portion of the 
lower part of the body, from the dia- 
phragm downwards, that is in contact 
with the frame of the chair, no vibra- 
tion whatever will be communicated: 
facts which ascertain, sufficiently, the 
extent and limits of the organization 
which contributes to vocal expression, 
For, if the vibration of the chair were 
merely a remote effect, of the nature of 
an echo, responding to the pulses of 
the external air, put into agitation by 
the voice of the speaker (an eflect also 
which, 
* The experiment may be repeated, with 
additional facility, in the common slipper- 
bath, properly filled so as to cover the 
shoulders, while the head projects over the 
rim. , 
oR 2 
