ABOUT THE LOWER RESONANCE 

Of the sympathetic vibration of a low string to the call of a high string, and of the possible consequences deriving therefrom. 

“Until now, scholars have not admitted that any sound was capable of sympathetically causing another sound, lower than itself, to vibrate sympathetically, whatever their concomitance (see d'Alembert, Helmholtz, Tyndall, Koenig, etc.). Now, it is the practical realization of such an experience that I come to discuss.

“The wise reservations of Helmholtz having made me skeptical with regard to the scientific value of the results obtained on the harmonium, I preferred the piano, which eliminates, as much as possible, harmonics, hums, etc. 

“Having practiced first octave, quintoyer in the treble, Yut z of the piano, then the neighboring notes, I soon became quite skilful in this preparatory exercise, so much so that I no longer needed to release from its damper the high string which was to vibrate sympathetically at the call of the fundamental sound of the series to which it belonged. 

“With this result acquired, I tried to obtain, from a sound lower than the note emitted, what the higher sounds had given me, fairly quickly. I had to achieve a hammering whose rhythm matched synchronically with the number of vibrations of the target string in order to succeed. 

“Finally, I had the satisfaction of hearing, very faintly, the low sound. 

“To be certain I wasn't objectifying a chimerical sound, I had competent witnesses--one of them a sensitive composer, the others poets--pass in front of my piano, in such numbers that it was no longer possible for me to doubt.”

Edmond Bailly, 1893