Sanka Coffee ad, illustrated by James Williamson (1899-1978)
"James W. Williamson was a self taught artist who sold his first work while still in college. Following his graduation from Yale in 1923 he became a regular contributor to all of the major publications, however, his longest association was most definitely with The Saturday Evening Post, with his work being featured in that most famous of weeklies for over thirty years. During that time he would also be involved in advertising work for such clients as Arrow Shirts, Ford, Paul Jones, Clicquot Club Ginger Ale and Yardley. He was elected into the Society of Illustrators Hall of Fame in 1984."
* Biographical information found at Legendary Auctions
* More examples in my James Williamson Flickr set