He turned it over to the United States government when the ship returned to Sag Harbor on October 14 , 1846 .
Cooper took with him the map that charted the islands of Japan that had been found on the disabled Japanese ship .
Cooper turned it over to the United States government when the ship returned to Sag Harbor on October 14 , 1846 .
Cooper took with him the map that charted the islands of Japan that had been found on the disabled Japanese ship .