Sound / by John Tyndall.

  • Tyndall, John, 1820-1893.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Sound / by John Tyndall. Source: Wellcome Collection.

    94/496 (page 70)
    from the note 16 and multiplying continually by 2, or more compendiously raising 2 to the 11th power, and multiply- ing this by 16, we should find that at 11 octaves above the fundamental note the number of vibrations would be 32,768. Taking, therefore, the limits assigned by Helm holtz, the entire range of the human ear embraces about eleven octaves. But all the notes comprised within these limits cannot be employed in music. The practical range of musical sounds is comprised between 40 and 4,000 vdbrations a second, which amounts, in round numbers, to 7 octaves.1 The limits of hearing are different in different persons. While endeavouring to estimate the pitch of certain sharp sounds, Dr. Wollaston remarked in a friend a total insen- sibility to the sound of a small organ-pipe, which, in respect to acuteness, was far within the ordinary limits of hearing. The sense of hearing of this person terminated at a note four octaves above the middle E of the pianoforte. The squeak of a bat, the sound of a cricket, even the chirrup of the common house-sparrow, are unheard by some people who for lower sounds possess a sensitive ear. A difference of a single note is sometimes sufficient to produce the change from sound to silence. ‘ The suddenness of the transition,’ writes Wollaston,4 from perfect hearing to total 1 * The deepest tone of orchestra instruments is the E of the double- bass, with 413- vibrations. The new pianos and organs go generally as far as C1 with 33 vibrations; now grand pianos may reach A11 with 27^ vibrations. In large organs a lower octavo is introduced reaching to Cu with 16? vibrations. But the musical character of all these tones under E is imperfect, because they are near the limit where the power of the ear to unite the vibrations to a tone ceases. In height the pianoforte reaches to alT with 3,520 vibrations, or sometimes to cT with 4,224 vibrations. The highest note of the orchestra is probably the dT of the piccolo flute, with 4,752 vibrations.’—Helmholtz, Tonempfinduvgcn, p. 30. In this notation we start from C with 66 vibrations, calling the flrst lower octave C1, and the second C11 ; and calling the first highest octavo c, the second c1, the third c, the fourth cul, &c. In England the deepest tone, Mr. Macfarren informs mo, is not e but a, a fourth above it.