The cello sonata was especially so plagued, as it grew out of sonatas for continuo; as late as the beginning of the 19th century it was still common for the cello in cello sonatas to double the left hand of the piano part, with the piano right hand playing obbligato figurations and melodies. Beethoven, indeed, is credited with composing one of the first cello sonatas with a written-out piano part.
The cello sonata was particularly affected, as it evolved from sonatas for continuo; by the beginning of the 19th century, it was still common for the cello in cello sonatas to double the left hand of the piano part, with the piano right hand playing obbligato figurations and melodies. Beethoven, indeed, is credited with composing one of the first cello sonatas with a written-out piano part.