CHAPTER 3 



Matter Waves: Sound 

 and Ultrasound 



(On Music and Noise "from 



CtoC," 



On Speech and Some Therapy) 



According to Sir Richard Paget, human speech began by the performance 

 of sequences of simple pantomimic gestures of the tongue, lips, etc. . . . 

 Consider the word "hither. " The tongue makes the same beckoning gesture, 

 while [one is] speaking this word, as is made with the hand. 



(H. Fletcher. 3 ) 



INTRODUCTION 



Our senses of touch and hearing reveal an environment which contains a 

 bewildering array of matter waves: the breeze; falling raindrops; noise, 

 speech, and music; earth tremors, shock, or blast waves; the vibrations en- 

 countered when riding a horse, or when operating a jack-hammer. Bees 

 and some other insects, and bats too, send and receive, and are guided in 

 flight by very high-frequency matter waves. 



Thus waves in matter have a great spectrum of manifestations, uses, and 

 effects. It is the purpose of this chapter to illustrate them, for matter waves 

 and electromagnetic radiations together comprise the most important 

 method of man's continuous exchange of force and energy with his environ- 

 ment. The latter are introduced in Chapter 4. They are fundamentally 

 very different from matter waves, although often confused with them. In 



47 



