AUER Max Joseph (1795 † 1878). [Head of an angel, after a Renaissance painting]. 1840. Galvanography, or Kobbel process. Proof on thin vellum. Small margins. 12.4 x 10.3 cm (sheet). One of the very first tests carried out using this process in Munich, in the "manner of washing". Condition B (corner mounted proof on laid paper). The Galvanograph was developed in 1840 by Franz Ritter Van Kobbel. "This process consists of executing a drawing with a litho pencil or encaustic ink [...]. ...] One works on silver plated copper which can be grained beforehand as for aquatinting. The non-drawn parts will be in relief" (A. Béguin, Dictionnaire technique de l'estampe.).