Fig. 7.1 Johann August Rosmaesler, Engraving published in Franz Seydelmann, Sechs Sonaten für zwo Personen auf Einem Clavier (Leipzig: Breitkopf, 1781).

Fig. 3.2 Antoine Jean Duclos, after Augustin de Saint-Aubin, The Concert, 1774. Etching and engraving. The Metropolitan Museum of Art, New York.

Fig. 1.5 Nicolaes Aartman, Interior with a Musical Gathering, c. 1723–60. Graphite and watercolor on paper. Rijksmuseum, Amsterdam.

Fig. 1.4 Gabriel Jacques de Saint-Aubin, The Musical Duo, c. 1772. Watercolor, gouache, brown and black ink, and graphite on paper. The Fine Arts Museums of San Francisco.

Fig. 1.3 Title page of Haydn, Piano Trio, Hob. XV:10 (Vienna: Artaria, 1798).

Fig 1.1 Heliogravure by Franz Hanfstaengl, 1907, after Julius Schmid, Haydn Quartet, c. 1905–6 (painting now lost). Vienna City Museum.