If the new Massachusetts Constitution said everyone was born flee and equal then it ""ought to mean what it says, and I want you to go to law for me and get the law to say I'm free."" Thus Elizabeth Freeman to Theodore Sedgwick in 1781--and thus she gained her freedom and thirty shillings damages from Colonel John Ashley in a groundbreaking case. For many years thereafter she served the Sedgwicks capably (and routed Shays' marauders majestically); lastly she worked as a nurse, ""the only person (according to Catherine Sedgwick) who could tranquillize my mother when her mind was disordered. . . and why? She treated her with the same respect she did when she was sane. . . in short, her superior instincts hit upon the mode of treatment that science has since adopted."" This last, from the introduction, is an eloquent testimonial; more dramatic, as Mr. Felton has recreated it, is Bet's gathering conviction--""by keepin' still and mindin' things""--that she ought to be free. Her speech is sometimes finicky, sometimes slurred, and altogether not quite natural; and lawyer Sedgwick is presented with a too-convenient train of thoughts (""Perhaps he had never realized the depth of the love of freedom in black people, even those as fortunate as Bet"" etc., etc.). But the book makes an effective heroine of a historical footnote, and it also makes good reading.