The cave art of the 20th century

That's what Marshall McLuhan called advertising. Paul Rand picked up on the theme in his book, From Lascaux to Brooklyn, and the last episode of AMC's Mad Men riffed on it in one of my favorite scenes in the series. I hadn't made this connection before, though: the children's book graphics of Leonard Weisgard, whose bio notes that he was influenced by primitive cave paintings . . .