In 1971, browsing in a French flea market, the art dealer John Kasmin found the postcard that turned him from a fan into a serious collector. It was made in 1906 by a Normandy printer from a photograph of two figures in a bare room. One is a man in an ermine-trimmed suit, the other is a bear, wearing a frock. They both wear rollerskates and appear to have just completed a slalom around some cider bottles. Both the man and the bear – whom the card names "Lolotte" – look exhausted and glum. "It is," the veteran gallery owner says, "just the most wonderful thing."