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ANNUAL REPORT SMITHSONIAN INSTITUTION, 19 3 2 



One is apt to forget, however, that at one time a noise is connoted 

 " an agreeable or melodius sound." In the Bible, Moses refers to the 

 " noise of them that sing," and David repeatedly enjoins us to " sing 

 and make a joyful noise." It is an easy step to the next definition : 



A band, or company of musicians. 



Shakespeare uses the word in this sense in King Henry IV (2, ii, 4) : 



And see if thou canst find out Sneak's noise ; 

 Mistress Tearsheet would fain hear some music. 



This obsolete association of noise with a band would seem to be 

 entering on a new lease of life, if one may judge from certain devel- 

 opments of modern music ! 



Figure 1. — Wave form of sound emitted by a motor generator set 



Most textbooks on physics would, I think, differentiate a musical 

 sound from a noise by investing the latter with a complexity arising 

 from complete irregularity of period, amplitude, and wave form. 

 In other words, a noise is to be regarded as a medley of notes of defi- 

 nite frequencies, the mixing being sufficiently random to obscure the 

 musical quality of the individual notes. See, for example. Figure 1, 

 from observations by Churcher and King. (Journ. Inst. Electr. 

 Engs., 1930.) 



As is very easy to demonstrate, it is, however, possible to generate 

 a note of high purity, but of such intensity or frequency as to be 

 voted a thoroughly objectionable " noise " by those who hear it. We 

 had better, I think, turn to the legal definition of noise. In law, 

 noise may be defined as an excessive, offensive, persistent, or startling 

 sound. Incidentally, by the common law of England, freedom from 

 noise is essential to the full enjoyment of a dwelling house, and acts 

 which affect that enjoyment may be actionable as nuisances. But 

 it has been laid down that a nuisance by noise, supposing malice to 



