334 On the Vibrations of Musical Strings. 



and he says it was near the Roman pitch. Dr. Young state;} 

 the number at the eighth power of 2, or 25G. In page 43(> 

 ot" the xxxvith vol. of the Philosophical Magazine, 240 is 

 given as the number, as it is also in the number for July 

 last, on the authority of Dr. Crotch. I have examined two 

 modern forks for this note, and have found one to make 

 254 ■- and the other 252| vibrations in a Bccond : so that 

 it appears there is no precise number of vibrations which 

 has yet been fixed upon as a standard of musical pitch. It 

 must be confessed that the number is purely arbitrary ; but 

 if that number shall be preferred which is more convenient 

 than another in this kind of calculations, and at the same 

 time approaches nearly to that which corresponds with the 

 present concert pitch, 252 is prob.ibly the best, being di- 

 visible by all the digits except 5 and 8. 



But whatever number may be fixed upon as a standard 

 by those interested in anv way in its determination, I am 

 persuaded that the following mode of ascertaining the 

 sound producible by any given number of vibrations will 

 be found very practicable and convenient. 



Take a fine steel wire, such as is used for the upper 

 strings of a harpsichord, and while it is stretched by a 

 weight ample enough to straighten it, measure and cut oft' 

 a yard long of it, and weigh it accurately in grains troy. 

 Suspend this piece by one end from a peg, and to the other 

 hang a weight, equal to as many pounds avoirdupoise as 

 the yard long of the wire weighed grains. If then the 

 wire be made to vibrate, and the length of the vibrating 

 part be hmited to 1 9-573 inches, the number of vibrations 

 in one second will be 252. If any other number of vi- 

 brations be wanted to be produced, divide 4932*34 by that 

 number, and the quotient will give the number of inches 

 to which the vibrating part of the wire must be limited 

 to produce it : thus, if 256 were wanted to be produced, 

 the length would be 4932, 34-f-25fi= 1 9-2b7 inches, &c.&c. 



A monochord constructed so as to have its wire nearly 

 vertical, and kept in tension by a weight proportioned as 

 aborc, would be very applicable to this mode of ascertain- 

 ing sounds. 



I have mentioned a fine steel wire, as being, T think, best 

 for the purpose ; but good brass wire will do equally well, 

 and so would catgut if it were not for its stretching pro- 

 perty, and the inequality of its diameter. In general it will 

 be found convenient to use a small ring of wire, and extend 

 it in the well of a staircase, so that while a weight is ap- 

 pendant to it five or six yards may be measured, and thea 



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