Anyone with reservations about Dr. Beaumont as a children's book hero will be reassured by the Epsteins' very first words--introducing their ""strange-but-true story"" of two men whom ""only an accident could have brought together."" Army surgeon Beaumont's lust for fame is emphasized from the start, as is his snobbishness; and his French-Canadian patient/guinea pig-to-be is first seen racing his voyageur's bateau onto Macinac Island and into a seasonal celebration which, as the Epsteins describe it, offers a vivid picture of the lusty voyageurs and a poignant one of what Alexis is soon to lose when an accidental gunshot wound leaves him near death. After he has healed, the hole in his stomach remains, ""rather like a mouth pursed up, ready to whistle."" And the doctor sees his opportunity--starving and stuffing, tricking, bullying, displaying, and virtually imprisoning Alexis as he dips bits of food into the hole to time their disintegration, removes gastric juices for test-tube digestion and analysis in Europe, lectures and writes of his findings, and achieves his fame. The experiments made spectacular news in the early 1800s and they are fascinating yet; and the Epsteins don't play up the exploitation angle but simply slip in well-chosen bits of evidence: when Alexis escapes to Canada, for example, Dr. Beaumont sets fur company agents to watching for the ""ungrateful wretch""; later, having lured him back, he signs Alexis into the army so he can hold him with warnings of the fate of deserters. Alexis perhaps has the last laugh, outliving the doctor by 27 years, during which time he continues to be studied--but with ""great courtesy"" and ""generous fees,"" for now he too is famous. From the pair who charmed us last year with Mr. Peale's Mamoth, another coup.