Hugh Huxley has devoted his career to answering the question of how muscles contract. Although his initial answer--the sliding filament theory--has since become part of every standard biology and physiology textbook, Huxley has relentlessly pursued the finer details of muscle contraction well into his seventies.

Huxley was born to a middle-class Welsh family in Birkenhead, Cavendish, England, in 1924. His father, Thomas, was an accountant for the post office. But both he and Huxley's mother, Olwen (Roberts), "were people of remarkable intellect, great readers, lovers of music and with great moral strength and power of judgment," Huxley wrote in an autobiographical essay in 1996. "They instilled in my sister and me the idea that if we worked hard and tried hard enough we would win scholarships to University, perhaps even to Cambridge." As a boy, Huxley developed an interest in physics, and tinkered with electric motors, shocking coils, and short-wave...