It's important for the one to become acquainted with a variety of sounds for his ventriloquist dummies. The sense of hearing is easily deceived-in fact, fast than other five senses - and in its judgment of sound of any kind relies largely on the memory of previous experiences, although such memory can be exercised involuntarily and sub-consciously.
The student has to therefore strive to obtain a good understanding of the pitch of sounds, irrespective of what nature, for everything audible. External sounds are be much modified according to speed and quality, because vibrations are prevented from straight getting into the ear-drum. Now if a few words are spoken with the ears closed, the sound will reach the auric nerves interiorally through the Eustachian tube at the back of the mouth, which conveys the vibration to the aural cavity instantly behind the drum of the ear.
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