Thanks to Wikipedia for information about this home (and its owner):  “Born in 1854 as Alfred Waterman Morgan, he was grandson of New York governor Edwin D. Morgan and changed his name to Edwin Denison Morgan III at the request of his grandfather.  He was the founder of Nassau Light and Power, a shareholder in livestock interests, and president of mining companies in Mexico.  His summer residence, Beacon House (this one) was nicknamed the “Acropolis of Newport” and completed around 1890, designed by architect Stanford White.  With deep water at both sides of the peninsula in Bretons Cove, he kept his yacht Constellation along with smaller racing yachts he owned while residing there. The card itself was mailed in 1908 with stamp and clear Newport postmark.  Grade: 1