244 Mr Dugald Stewart on Ventriloquism. 



I was much pleased to observe the coincidence between 

 both these remarks, (which struck me when I first read Mr 

 Gough's paper,) and the following strictures on his theory of 

 ventriloquism, in a very ingenious article of the Edinburgh 

 Review. After quoting the same passage which I have already 

 referred to, the reviewer proceeds thus : 



" Though this comprehends the scope of the authors doc- 

 trine, we are of opinion that it affords a deficient and inade- 

 quate explanation even of the case that he relates, in which 

 the ventriloquist performed his operations in a confined room. 

 The power of projecting the voice against a plain wall, so that 

 it shall be reflected to a given point, is difficult, and we may 

 almost say impossible of attainment. But, granting that this 

 power were attained, the reflected tones of the voice must be 

 a mere echo, whilst the sounds proceeding immediately from 

 the mouth of the speaker, being both louder in degree, and 

 prior in point of time, must necessarily, as is the case in every 

 echo, drown the first parts of the reflected sounds, and make 

 the remainder appear evidently different from the original. 

 The author seems to have been led into this theory by the 

 analogy of light, without perhaps duly considering that the 

 particles of light move successively in direct lines ; whereas 

 the undulations of sound must necessarily expand and en- 

 large, as they proceed on from the sounding body. But the 

 feats of ventriloquism are often performed sub dio, when no 

 means for reflecting the voice can be present, and where, of 

 course, the author's doctrine cannot in any respect apply. 

 He has omitted to mention a cause which has a very power- 

 ful influence in effecting the deception, viz. the expectation 

 excited in the spectator or hearer, by the artist having pre- 

 viously informed him from whence he proposes to make the 

 sounds proceed. This circumstance, of raising expectation 

 almost to belief, aided by a peculiarly happy talent for imi- 

 tating singular or striking sounds, such, for example, as the 

 cries of a child in the act of suffocation, is perhaps a more 

 probable explanation of the phenomena of ventriloquism."* 



In the conclusion of the foregoing passage, the reviewer 

 alludes to the influence of Imagination in aiding the illusions 



• Edinburgh Review, Vol. ii. pp. 194, 195. 



