Captain Josiah Parsons (1750–1807), a veteran of the Revolutionary War, built this Federal style house in 1792 overlooking Greenleaf Cove, where he had a grist mill.

Parsons became the second largest landholder in Westport and, by 1815, operated the only store, or trading post on the island. The Trading Post, built over the water with a boathouse underneath, provided for the needs of the island inhabitants. The original counter, cash drawer, and store kerosene lanterns are still intact. 

Captain Parsons was buried in the family burying ground not far from the house. Etched in his gravestone were the words “He was a Patriot of Bunker Hill.”

In 1964, scientist John C. Lilly, M.D., purchased the Parsons property and constructed a concrete pool which he and Mrs. Lilly used in the summer while conducting communication research with dolphins. Dr. Lilly’s books Man and Dolphin and Mind of the Dolphin, led the Washington Post to call him “one of the most original and fascinating scientists of our time, . . . He is one of the pathbreaking explorers of that great terra incognita, the human brain.”

The Parsons homestead was added to the National Register of Historic Places in 1982.