Tone-limit apparatus, for high notes of high pitch.

Made by G. Appunn & Sons.

This apparatus was designed for determining the highest vibration-frequency which is recognized by the ear as a musical tone. It consists of 31 small tuning forks, giving the diatonic scale

c ;        d ;        e ;        f ;         g ;        a ;        b ;        c ;

1    :   9/8   :   5/4   :   4/3   :   3/2   :   5/3   :   15/8   :   2

or   24   :    27   :    30   :    32   :    36   :    40   :    45     :   48.

through an interval of  4 octaves and a third, namely, from civ  = 2084 to eviii = 40,960.

In order to be able to determine with the apparatus and to perceive better and more distinctly the ascending scale up to the highest pitch, it is found advisable to produce the scales in octaves with two bows, and thus to sound every tone with its octave simultaneously, or one directly after the other.

As with the lower limits of audition, so with the higher, a good many different figures are given, the limit being very uncertain, and varying considerablyin different individuals. Captain Galton, using whistles, has gone even higher thanthis 40,960 of Appunn’s. Preyer gives the limits as from 16-24 to 41,000, but many persons of fair hearing capacity cannot hear above 16,000, while the ordinary range of musical notes is from 40 to 4,000.

(See Stone’s “Sound,” 1879, pp 75, 76.)

N.B. The above description is from the Science Museum’s technical file T/1876-469.

It was written by Alexander J. Ellis, who acquired the apparatus for the South Kensington Museum’s collection in 1876.