and on Reed Organ-Pipes. 241 



and beyond this note in singing, it will be found impossible to 

 pronounce a distinct O. 



The short and long U however are indefinite in their lengths, 

 the short U (as in but) seems to be the natural vowel of the 

 reed, and as this is but little affected by the pipe, except in 

 loudness, between O and b (No. 1.) this vowel will be found to 

 prevail through a long space, and upon approaching b, to change 

 gradually into the long U, (as in boot), which always appears 

 more perfect the longer the distance ab can be made. When 

 reeds of high pitch are used (as in No. 3.) the vowels always 

 become indistinct in the neighbourhood of b, and with bass 

 reeds there appears to be a series of vowels like the former, 

 on both sides the points b, d, &c. (No. 1.) but differing from the 

 other, both by being much less distinct, and also by each vowel 

 occurring at twice the distance from these points that it does 

 in the other series from a, c, &c. after the manner of No. 4, 

 where this new series is marked with an accent. 



No. 4. 



I E A O ,U A' E- I' r E' A' U O A E I 



a b c 



Cylinders of the same length give the same vowel, whatever 

 be their diameter and figure. This may be conveniently shewn, 

 by attachipg a reed R, Fig. 11, to a portevent T, terminating 

 in a horizontal flat plate ff^X covered with soft leather*. Tin or 

 wooden tubes of any figure, open at both ends, and made flat 

 at the bottom so as to fit air-tight to the leather plane, may 

 then be applied, as in the figure, and their effect upon the reed 

 tried. Another such leather plane. Fig. 12, may be provided, but 

 furnished with an embouchure at JV, like that of a common 



* The diameter of my plate = 3 inches. 

 Vol. III. Part I. H H 



