How to wash a cat

"Uncle Oscar was one of a kind. His dusty antiques shop, the Green Vase--nestled in San Francisco's historic Jackson Square neighborhood--was like his own personal museum to the Gold Rush era. Needless to say, I was shocked when he was found dead in his shop, and even more surprised to discover he'd left the venerable establishment to me...Before long, I learned my inheritance included all sorts of clues Uncle Oscar has left behind--a peculiar key, a trap door, a puzzling map..."--p.[4] of cover.