Oblong 8vo (postcard). ½ page.
Inscribed to the German dermatologist Alwin Scharlau.
Applying himself to painting interiors, portraits and nudes in a highly expressive impressionist style, Keller specialized in depicting female figures and achieved success as an artist in 1873 when he was awarded a medal for his work "Chopin" in Vienna.
Traces of a postmark; one small abraded spot. Self-addressed by the collector on the reverse. The Mecklenburg physician Scharlau (b. 1888) assembled a collection of artists' autographs by personal application.