Bowed idiophone << Back exhibit information online Glass harmonica probably German circa 1800 Inv.-Nr. 351 Bowed idiophone exhibited in  The Romantic Period from the instrument collection  Paul de Wit     "...and so it began to play, producing the most haunting tones I had ever heard." Thus Gottfried Keller described a private evening recital on the glass harmonica. Indeed, the ethereal sounds of the glass harmonica impressed listeners in the decades before and after 1800 to an extent not matched by the impressions made by any other contemporary instrument. Christian Friedrich Daniel Schubart recommended that only a sensitive player whose "heart's blood trickles from his fingertips" be allowed to play this "deeply-moving, melancholy instrument." Pushkin found something "other-worldly" in the instrument's "magical tones." Mozart, Beethoven and Donizetti all wrote for the instrument. The glass harmonica produces sounds when the player's wetted fingers are rubbed against the rims of the instrument's revolving glass bowls, which are set in motion by a treadle. The instrument's carefully tuned glass bowls were arranged in a manner similar to a keyboard. This glass harmonica was fitted with 37 glass bowls, ranging chromatically over three octaves.