The nail violin (also called nail harmonica) was an invention of 1744 by Johann Wilde from Petersburg.
The musical instrument was made up of a number of pitch-tuned metal pins (nails) that were fastened around a wooden sound box. The instrument was played with a (violin) strap by touching the pins. The nail violin gave a high pitch.
The oldest nail violin was presumably equipped with nine pens, and is located in Eisenach in the Bachhuis. Typically 37 pins were used, and in New York there is an instrument with 66 pins. The sound box is usually half to full. It is not possible to accurately determine what the original form of the instrument was. Only few copies have been preserved. In the Nordiska Museum in Sweden there is another instrument from 1792. variants
There is a type of nail violin that also knew strings next to the pins. This instrument had 49 pens. The development of this instrument goes back to the Bohemian builder Senal, and is known as Violino Harmico or Violino-Harmonika. Such an instrument is in any case documented on concert trips by Germany.
The original stringless form was rebuilt under the name Duolon in 1912, with the pins being tuned by the addition of an adjustable screw to the sound bars.
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