Few parents or children are likely to visit their local bookstore in search of stories concerning ancient Greek scientists. And that is unfortunate, because Kathryn Lasky has written a wonderful biography of the geographer Eratosthenes: The Librarian Who Measured the Earth (Little, Brown and Company). This book, illustrated by Kevin Hawks, is an excellent read-aloud for ages ten and under and can be read independently by children at a fourth-grade reading level.
Eratosthenes (pronounced AIR-uh-TOS-thuh-neez) was a third-century B.C. Greek who became head of the great library of Alexandria and wrote the first comprehensive geography text. From the time he was a baby, Lasky declares, he wanted to learn all he could about the world around him, and this life-long curiosity is portrayed in an appealing, positive manner by both text and picture. One illustration shows Eratosthenes crawling intently across the kitchen floor to follow the path of some ants; the final illustration shows him as an old man still gazing with questions at the stars.
Children will learn that Greeks before Eratosthenes knew that the Earth was round but did not know its size because the world was too large to walk or sail around. Greeks also knew the basic principles of geometry, but as of 250 B.C. no one had figured out a method of using geometry to calculate the earth's circumference. This biography focuses on Eratosthenes' quest to do just that, a quest so successful that the figure he calculated more than two thousand years ago differs from the modern figure (24,902 miles) by only about two hundred miles-an error of less than 1 percent.
Although Eratosthenes' reasoning technically involves trigonometry, it is presented simply, moving step by step and using the analogy of a grapefruit. Nevertheless, parents with a limited knowledge of higher mathematics may wish to review the details of Eratosthenes' method before reading the book to their children.
The Librarian Who Measured the Earth will appeal to Objectivists for several reasons. First, it is an uncompromising tribute to the curiosity and power of man's mind. Secondly, it is one of the very few children's books that explicitly shows how new knowledge builds on and expands existing knowledge. Most important, Eratosthenes is portrayed as a hero because he used his mind, not because he prayed to God or protected the environment. On bookshelves filled with biographies of Mother Teresa and Rachel Carson, The Librarian Who Measured the Earth is a treasure.
Two additional notes: First, parents with young children may wish to read this book in conjunction with Patricia Lauber's How We Learned the Earth is Round. This delightful book debunks the notion that no one before the modern era knew the world was round, explaining what observations led the ancient Greeks to deduce correctly the shape of the Earth. Children will enjoy duplicating the demonstrations using everyday household items. Secondly, Lasky has written many other children's books and I rate them "acceptable-but-not-outstanding." The Librarian Who Measured the Earth is a relatively recent book (1994) and, hopefully, marks a new trend in her work.
Mary Heinking is a project director with a major engineering and construction company. She lives with her husband in Sugar Land, Texas, where they home-school their six-year-old daughter.
[Editor's note: Although "The Value Exchange" is currently seeking to introduce Objectivists to enjoyable novels, biographies for children seem to fit in naturally. Given the degree of simplification, stylization, and idealization involved, they are far more like fiction than they are like authoritative, warts-and-all biographies.]