A Dictionary of Music and Musicians/Scheibler, Johann Heinrich

SCHEIBLER, Johann Heinrich, born at Montjoie or Montschau, near Aix-la-Chapelle, Nov. 11, 1777, died Nov. 20, 1837, silk manufacturer, after many travels, settled down at Crefeld, where he was first-assistant-Bürgermeister. In 1812–13, after some interesting experimental with Jews-harps, he turned his attention to the imperfections of existing means of tuning. He first tried a monochord, but finding that he could not always get the same note from the same division of his monochord, he endeavoured to help himself by beats, and discovered that each beat corresponded to a difference of two simple vibrations or one double vibration in a second. His plan was to fix the monochord by finding the stopped length which would give a note beating four times in a second with his own fork. Then, after endless trials and calculations, he found similar places for all the divisions of the scale, and finally from the monochord made forks for each note of the perfectly equally tempered scale By repeated comparisons with his forks he found that it was impossible to make a mathematically accurate monochord, or to protect it from the effects of temperature. He then hit upon the plan of inserting forks between the forks of his scale, from the lowest A of the violin to the open A, and counting the beats between them. It was this counting that was the trouble, but by highly ingenious mechanical contrivances he was enabled to complete the count of his fifty-two forks within from .0067 to .00083 beats or double vibrations in a second, and hence to tune a set of twelve forks so as to form a perfectly equal scale for any given pitch of A. The particulars of his forks, and the mode of counting them are contained in his little pamphlet 'Der physikalische und musikalische Tonmesser' (Essen, Badeker, 1834, p. 80, with lithographic plates),^[1] from which the preceding history has been gathered. During his lifetime he issued four smaller tracts, showing how to tune organs by beats, which were collected after his death as H. Scheibler's Schriften, etc.' (Crefeld, Schmüller, 1838). This is quite out of print, but copies of the former book are still to be bought. His wonderful tonometer of fifty-two forks has completely disappeared. But another one, of fifty-six instead of fifty-two forks, which belonged to Scheibler still exists, and was inherited by his daughter and grandson, who lent it to Herr Amels, formerly of Crefeld, who again lent it to Mr. Alexander J. Ellis, who counted it, and having checked his results by means of McLeod's and Mayer's machines for measuring pitch, gave the value of each fork in the Journal of the Society of Arts for March 5, 1880, p. 300, correct to less than one-tenth of a double vibration. The two extreme forks of this 56-fork tonometer agree in pitch precisely with those of the 52-fork tonometer, but no other forks are alike, nor could the forks of the 52-fork tonometer have been easily converted into those of the other one. In 1834, at a congress of physicists at Stuttgart, Scheibler proposed with approval the pitch A 440 at 69°F. (=A 440.2 at 59°F.) for general purposes, and this has been consequently called the Stuttgart pitch.^[2]

[ A. J. H. ]

1. 'The physical and musical Tonometer, which proves visibly by means of the pendulum, the absolute numbers of vibrations of musical tones, the principal kinds of combinational tones, and the most rigid exactness of equally tempered and mathematical just chords.'
2. He selected it as the mean of the variation of pitch in pianos as then tuned at Vienna, and not from the fact that it enables the scale of C major, in just intonation, to be expressed in whole numbsrs, as has been sometimes stated.