Giving David a Bath

Florence's art treasures are world-renowned. But you wouldn't be able to see the masterworks of Leonardo da Vinci, Michelangelo, Botticelli, and so many others if it weren't for the contributions of generations of low-profile arts patrons. These days, much of that patronage comes from outside Florence and even outside Italy; walk through the Uffizi and you'll see restorations paid for by groups of art lovers in locations from Kyoto to Cleveland.

And so when Countess Simonetta Brandolini d'Adda, an American who has lived in Florence with her Italian husband for 30 years, saw the need to help protect...