remarkable c. 1940's antique american industrial heavily embossed or stamped brightly colored antique american industrial exterior downtown chicago city street "keep chicago clean" sign likely fabricated by the leslie sign company (chicago, ills.) for the chicago bureau of sanitation. the sign contains rounded edges with holes in each of the corners for mounting flush against a wall, etc. slight surface wear, minor discoloration and sporadic spots of paint evident. very hard to find.