Latitude: How American Astronomers Solved the Mystery of Variation



First longitude, now latitude. From Latitude's title we cannot help thinking of Dava Sobel's recent bestseller, Longitude. I suppose it's unlikely to be such a moneymaker, but this delightful new book by Bill and Merri Sue Carter, a father and daughter team, is similar to Sobel's book. Both are physically small, with short chapters, which makes for a quick read. And both have a clear hero: John Harrison and his chronometers for longitude; and Seth Carlo Chandler Jr. and his almucantar for latitude. Both books eschew academic-style footnoting, although Latitude does list a few useful sources for each chapter and provides a comprehensive list of Chandler's astronomical publications.

Chandler's name is known to most AGU members for its association with the 14-month wobble of the Earth's pole. He also discovered the slightly smaller annual wobble, and an argument can be made that he was the principal discoverer of polar motion, or latitude variation, in general.