Long heralded as a city treasure herself, expert "mudlarker" Lara Maiklem is uniquely trained in the art of seeking. Tirelessly trekking across miles of the Thames' muddy shores, where others only see the detritus of city life, Maiklem unearths evidence of England's captivating, if sometimes murky, history--with some objects dating back to 43 AD, when London was but an outpost of the Roman Empire. From medieval mail worn by warriors on English...