Keyed harmonica

Keyed harmonica (Fr.: harmonica à clavier; Ger.: Tastenharmonika; It.: armonica a cembalo), *glass harmonica furnished with a keyboard. Early attempts at attaching a keyboard to the instr., made from 1769 on, were unsuccessful. An experimental model was first produced in 1782, but models with keyboards were not marketed until 1784. Hessel of St. Petersburg supplied them a year later, and in 1798 Carl Röllig improved them. Additional improvements were made in the 19th c., when the compass was…