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PROCEEDINGS OF THE AMERICAN ACADEMY 



being conducted in a hall was i^robably inconsiderable, as the hall was 

 92 feet long and 65 feet wide; and, moreover, the windows were 

 partially open. It should be remarked, that bringing the resonators 

 too near the pipe introduced an error of a nature and magnitude which 

 indicated that for a sound of considerable intensity the resonance 

 was not proportional to the intensity of sound at the mouth of the 

 resonator ; but this exception only serves to prove the rule for the 

 case of moderate intensity. 



It is true that these experiments do not furnish an exact proof of 

 the law of inverse squares for sound ; but we have not an exact proof 

 of the same law in the cases of light and heat. All that we can say 

 of any of them, on experimental grounds, is, that they are very 

 approximately true. 



The above experiments show that we may make this assertion for 

 sound on as valid experimental grounds as for light or heat. 



