Carl Engel, Musical Myths and Facts, Volume 2…
“ To note a curious instance in proof of the correctness of this assertion as afforded by the clavichord, a contemporary of the harpsichord and predecessor of the pianoforte:—The strings of the clavichord are not sounded by being twanged with quills, as is the case in the harpsichord, but are vibrated by means of iron pins, called tangents, which press under the strings when the keys are struck. The pressure of the tangent lasts as long as the key to which the tangent is attached is held down. ”
