Dr. Young's Experiments and Inquiries, Sec. 107 



The frequency of vibrations constituting a given note. XIII. 

 The vibrations of chords. XIV. The vibrations of rods and 

 plates. XV. The human voice. XVI. The temperament of 

 musical intervals. 



I. Of the Quantity of Air discharged through an Aperture. 



A piece of bladder was tied over the end of the tube of a large 

 glass funnel, and punctured with a hot needle. The funnel was 

 inverted in a vessel of water; and a gage, with a graduated glass 

 tube, was so placed as to measure the pressure occasioned by 

 the different levels of the surfaces of the water. As the air 

 escaped through the puncture, it was supplied by a phial of 

 known dimensions, at equal intervals of time; and, according to 

 the frequency of this supply, the average height of the gage 

 was such as is expressed in the first Table. It appears, that the 

 quantity of air discharged by a given aperture, was nearly in 

 the subduplicate ratio of the pressure ; and that the ratio of the 

 expenditures by different apertures, with the same pressure, lay 

 between the ratio of their diameters and that of their areas. 

 The second, third, and fourth Tables show the result of similar 

 experiments, made with some variations in the apparatus. It 

 may be inferred, from comparing the experiments on a tube 

 with those on a simple perforation, that the expenditure is 

 increased, as in water, by the application of a short pipe. 



P2 



