ON MUSICAL INSTRUMENTS. 



407 



actions may perhaps also be considered as tending to illustrate the vi- 

 brations of chords. The latest improvement which deserves to be mention- 

 ed, with respect to the theory of sound, is Laplace's explanation of the increase 

 of its velocity on account of the effect of heat, which appears to afford a 

 satisfactory explanation of a difficulty so much the more important, as it 

 tended to lessen our confidence in every part of a theory, which differed so 

 widely from the most accurate and best established observations. 



CHRONOLOGY OF ACUSTICS. 



