The Discovery of Longitude

Gr 3–6—It is unclear who the target audience is for this picture-book history of the invention of the ship's clock. The text explains the difficulties of keeping accurate time on a ship and why it was essential. Unlike Louise Borden's Sea Clocks: The Story of Longitude (S & S, 2004), there is no biographical context given to inventor John Harrison's life and few pages are devoted to his work inventing and experimenting with clocks. The vague time line of Harrison's efforts at the end is more detailed than the text itself. There are some informative diagrams, but the lack of a glossary, index, or "detailed map of the world in the 1700s"-as promised on the book jacket-reduce the book's research value. It is unlikely that a middle-grade student would select this book voluntarily, though the relatively simple sentences, with unfamiliar words defined in context, and short paragraphs are conducive to independent reading. The strongest facet is the paintings of life at sea that appear on every page, but they are not enough to merit inclusion in most collections. Borden's book as well as Kathryn Lasky's The Man Who Made Time Travel (Farrar, 2003) are still the go-to titles on this topic.—Rebecca Dash Donsky, New York Public Library