Foster's latest exercise in simultaneous bio-history uses the airplane's invention as an earmark of the period, and intersperses three installments of the Wright brothers' story with profiles of ten other movers and shakers who--except for Mao, a child of seven at the time of the Boxer Rebellion featured in the China sketch--were active during the first decade of our century. As usual Foster's pace is brisk and her method dramatizes the coexistence of such diverse and far-flung figures as Teddy Roosevelt, Marie Curie, Marconi, Ford, and Peary. But, also as usual, her glimpses of the individuals are so fleeting that one learns essentially nothing about Einstein's theory of relativity, Freud's discovery of the unconscious, or the career of Lenin, who is seen here as a young man in Siberia. Most of the separate portraits are totally unrelated to each other except for some smooth but superficial transitions. And as they are also unrelated to any general background--whether it be larger political or intellectual currents or small details of food, clothing, and home life, the parts never blend to evoke a taste of the period.