Max Joseph von Pettenkofer, (1818-1901) Bavarian chemist and hygienist, is:

“most familiar in connection with his work in practical hygiene, as an apostle of good water, fresh air and proper sewage disposal. His attention was drawn to this subject by the unhealthy condition in Munich in the 19th century.” 1.

1. Wikipedia website entry for Pettenkofer accessed 2011.

Müller, of Munich,  was the Photographer to the Court of Bavaria.

Engraved outside plate margin lower left corner: Hofphotograph F. Müller, München. phot.