Before he ever tackled writing for young readers, Theodore Seuss Geisel made a living illustrating advertisments of all kinds. This beer ad is part of the Dr. Seuss Collection at the Mandeville Special Collections Library at the University of California, San Diego. Flavorwire has a gallery of twenty examples that display Dr. Seuss's particular style that you know so well from his children's books. Link -via Nag on the Lake
(Image credit: Schaeffer Bock Beer advertisement, Dr. Seuss Collection, MSS 230, Mandeville Special Collections Library, UCSD)