Looking at the island of Palm Beach today, with its unmatched mansions, tony shops, and pristine beaches, one is hard pressed to visualize the dense tangle of Palmetto brush and mangroves that it was when visionary entrepreneur and railroad tycoon Henry Flagler first arrived there in April 1893. Trusting his remarkable instincts, within less than a year he had built the Royal Poinciana Hotel, and two years later what was to become the legendary Breakers--instantly...