Limburg, a Bedford, N.Y., freelance specializing in oceanography and marine science, has written about the art, science, and technology of locating the wreckage of ships and aircraft — and their unfortunate passengers. In the past, wrecks have often sunk in waters too deep for conventional divers to gather evidence that could be used for interpretation in shore-side labs. Behind each wreck, Limburg writes, is the human tragedy, and behind that lies all too often corporate greed, official corruption, and individual villainy.