Captain Phillip L. Cosgrove, Sr., commanded the U.S. lighthouse tender Mangrove, the first rescue ship to aid victims of the 1898 explosion of the U.S.S. Maine in Havana harbor. This house, acquired by Cosgrove in 1871, incorporates remnants of federal judge James Locke's one-story residence. In order to accommodate his growing family, Cosgrove paid $1,600 to enlarge the house to 2 1/2-stories. Remodeled in the Greek Revival style, it features a gabled roof with jig-cut balusters and decorative scrolls at the tops of the square columns. Adaptations to the Key West climate were also incorporated, including a cistern under the floor with fish to help keep water fresh and keep out mosquitos. Cosgrove served in the Lighthouse Service until 1906, when his son, Phillip, Jr., took over his command. Three generations of the Cosgrove family occupied the house until 1947, when the house was acquired by William Gamble (1916-1976), a local jeweler and Key West city commissioner. Following Gamble's death, the house was converted in 1978 into a resort. The Cosgrove House reflects Key West's unique Conch architectural style, and was listed on the National Register of Historic Places as part of the Key West Historic District.