What did William Starling write on the postcard that he sent to Max?

From the text:

The great bard WS says it best: “ The rich oft underestimate beauty’s lasting embrace,” he read, and looked up again, confused. “That’s not really Shakespeare.”

Grammie shrugged. She had no answers.

Well, our dear Arabella has riches and beauty both now, the card said. After that, however, his father wrote something that actually sounded like him: The adventure is under way!