Breitkopf & Härtel is the world's oldest music publishing house. The firm was founded in 1719 in Leipzig by Bernhard Christoph Breitkopf. The catalogue currently contains over 1,000 composers, 8,000 works and 15,000 music editions or books on music. The name "Härtel" was added when Gottfried Christoph Härtel took over the company in 1795. In 1807, Härtel began to manufacture pianos, an endeavour which lasted until 1870. The Breitkopf pianos were highly esteemed in the 19th century by pianists like Franz Liszt and Clara Schumann.