By Anthony Flint, Random House, New York, N.Y. 256 pages, $27.

Along with his nemesis, Franklin Roosevelt, Robert Moses was arguably the most influential New Yorker of the 20th century. For nearly 40 years, Moses wielded enormous power in shaping modern New York through a large number of state and local commissionerships and authorities. During Moses’ day, which began under Governor Alfred Smith and ended under Governor Nelson Rockefeller, he was intimately involved in planning, financing, and building hundreds of parks, highways, tunnels, housing complexes, bridges, beaches and two worlds fairs.