An 1891 painting of the Heckmann coppermill by unknown artist, at the Deutsches Historisches Museum, Berlin. In 1837, Carl Justus Heckmann (1786-1878) founded a copper mill at Schlesisches Tor, Berlin. Between 1840-1850, it was a leading company with numerous branches in the German Reich. In 1868, Heckmann retired from business and his sons continued the company. The painting was a gift to the foreman, C.W. Meyer, who can be seen on the right edge.