Nim Chimpsky, the waggishly named chimpanzee who was taught by Terrace (psychology, Columbia) and associates to communicate with humans in American Sign Language, has appeared on TV and on the cover of New York magazine; and his linguistic achievements have been thoroughly reported and analyzed in Terrace's scientific papers. This is the story not only of Nim's progress with language but also of his socialization and his emotional life--and of the project itself: the squabbling over discipline and teaching methods, the time-consuming and ultimately defeating scramble for funding, and the consequent, disheartening turnover of volunteer teachers. Terrace's plan was to combine an intensive and carefully documented classroom program with the experience of a human home which would provide the motivation that a child has to express his feelings and views. But the woman who had been eager to serve as Nim's foster mother and chief teacher bowed out after a year and a half; and all three of the talented young teacher-caretakers who then lived with Nim in a Riverdale mansion (formerly occupied by Columbia's president Grayson Kirk) left the following summer. Altogether, 60 volunteers contributed to Nim's education during the four-year experiment, and several times that number met with him in trial sessions. Such discontinuity would surely traumatize a human child, and Terrace believes that the setbacks and depression following the departure of his beloved family of three had a permanent adverse effect on Nim's development. Another, regularly staffed and better controlled five-year experiment, he believes, would be well worth the eight full-time teacher-caretakers (""preferably eight full-time equivalents of Anne Sullivan"") and over one million dollars it would require. Meanwhile, though, after rigorously analyzing Nim's utterances and studying reports and films of other experiments, Terrace concludes reluctantly that despite frequent combinations of signs, a chimp's ability to create true sentences (the current criterion for human language mastery) has not been proved. One regrets the inconclusive results and the sad necessity to abandon Nim, at four, to an institutionalized existence--but Terrace's critical severity toward his own findings is as impressive as his account of his parting with Nim is moving. Illustrated with nearly 250 photos documenting Nim's signing behavior, engaging ways, and affectionate nature.