Dennis Wilson, founder of the Beach Boys, has always felt that the land, with its natural and manmade boundaries, restricts not only his personal lifestyle but also his creativity, The only place I can really feel free, he says, is on the sea. His first boat was a seventeen-foot Tahiti runabout, but it wasn't until 1968, when he bought a twenty-five-foot cabin cruiser, that he was able to take up residence on board a ship. He's lived on his present yacht, a fifty-foot, twin-mast ketch named Harmony, since 1976.