In a bygone era when twentieth-century Proper Bostonians mixed Beacon Hill formalities with countryside pleasures, Margaret Pearmain Welch (1893-1984) defied the mores of her social set and got away with it. She was the epitome of everything expected and much that was scandalous. Known as a debutante, dancer, world traveler, and hostess, she was also an indefatigable activist, writer, lecturer, lobbyist, fundraiser, and opinion shaper–grande dame as well as proverbial little old lady in combat...