Islip Art Museum, Islip, New York
(c)2009 DSThemelis
Visited the museum in October. The grand mansion, with 41 rooms including a ballroom, was Brookwood Hall, built in 1903 by Harry K. Knapp. What a grand place this must have been on Long Island. Not too many of these left in good condition, unfortunately.
http://www.eastislip.org/Pages/Estates/BrookWood%20Hall%20History/Thorne%20Estate/Knapp&Thorne.htm