Medicine: Amphibious Doctor

Woolly summer fogs and bitter March nor'easters sometimes hold up even the U.S. mail boats that ply among the 172 islands of the San Juan group at the north end of Puget Sound, but nature seldom stays Dr. Malcolm Heath, 43, from his appointed rounds. By airplane, ferry, small boat and (in far-from-rare emergencies) Coast Guard cutter or seaplane, Dr. Heath brings a frontier brand of modern medicine to the islands' 7,000 residents and summer visitors. He is the only doctor in the islands and one of the most remarkable G.P.s anywhere in the...