Not accident, but a natural law based on deep bio-social necessity determines the pattern by which people settle in towns of different sizes. Such is the simple conclusionwith arresting implicationsof Lecturer George Kingsley Zipf of Harvard, who analyzes the mathematics of population distribution in his new book, National Unity and Disunity (Principia Press; $3.50).
"If the reader will consult the census of the U.S. for 1930 he will note a very curious relationship between all the communities that contain at least 2,500 inhabitants. Thus he will find that New York was first in size . . . that the second largest city...