The Voice and its Modifications. 81 
To produce intensity in the voice we all know that the mouth is 
open, the velum palati raised and the position is nearly the same as 
in declamation, and all who have seen ventriloquists must be convin- 
ced, that they cannot practise their art and use the mouth as those 
who wish to be heard at a distance, for in the latter case the stock of 
air is rapidly exhausted and the principal requisite for ventriloquists 
is to hold this collection for use. It is curious that the attention of 
physiologists has not been directed to the action of the muscles of 
the thorax and more especially of the diaphragm, in accounting for 
ventriloquism. ‘The muscles called into action during inspiration are 
the internal and external inter-costales, the diaphragm and the sub- 
clavius which are occasionally assisted by the latissimi dorsi, the pec- 
toralis, the scaleni, the sterno-mastoidei, the serrati magni and the 
serrati postici superiores. 
In expiration, the muscles that act are the diaphragm (which di- 
lates,) the recti, the obliqui externi, and the interni abdominis, the 
sterno-costales and the transversales, aided sometimes by the longis- 
simi dorsi, the serrati postici inferiores, the serrati magni, the quad- 
rati lumborum and the pyramidalis. The diaphragm is relaxed in 
expiration and consequently rises, which movement I may compare 
to the resilience of a sponge from which a contracting force has been 
removed and of course it expands, and thus this muscle presses on 
the pleura and lungs, and altering the force of the current. of the 
air from the lungs as it acts with more or less vigor. ‘The diaphragm 
or midriff contracts in inspiration and the force and extent of its 
contraction must regulate the quantity of air admitted into healthy 
lungs. Ihave referred to the power of pearl divers in this respect 
and the application is equally appropriate to ventriloquists. 
Before entering on this subject, it will not be irrelevant to give the 
opinion of others concerning the manner in which this art is created. 
Formerly it was thought that ventriloquists were gifted with a double 
larynx and this notion may have been imbibed during the reign of 
comparative anatomy, but human dissection has refuted the doctrine. 
Richerand, at first believed, that the art resulted from the possession 
of the faculty of holding in the stomach, as in a store house, a larger 
quantity of air to be used by the performer as it was wanted. He 
afterwards abandoned this explanation. Mr. Gough, was less satis- 
factory in his doctrine of echoes; since the shape and size of the 
room and even the open air do not hinder the exhibiter from practis- 
ing this art. ‘The theory of Haller, Mazer De Bonn, can easily be 
Vou. XXVI.—No. 1. 11 
