A couple days ago a friend told me about the book Carry On, Mr. Bowditch, a fictional account of the life of Nathaniel Bowditch (1773–1838). I’ve been listening to the book on Audible, and apparently it’s only lightly fictionalized.
Bowditch was a self-educated mathematician and astronomer, best known for his book The American Practical Navigator, first published in 1801. The book has been continually revised over the last two centuries and is still in print, available for download from the National Geospatial-Intelligence Agency. The latest edition begins with a brief account of Bowditch’s life, confirming the essential details of the fictional biography.
Two things stand out about Bowditch: his attention to detail and his desire to make ideas accessible. He taught himself Latin in order to read Newton’s Principia and followed the text so closely that he found a number of errors.
Bowditch’s navigation book grew out of the numerous corrections he made to error he found in John Hamilton Moore’s The Practical Navigator, the leading navigation text of the time.
At the beginning of the 19th century it was theoretically possible to determine time, and hence longitude, from lunar observation. However, the method required ideal observation conditions and laborious calculation. Bowditch developed a way to make the necessary measurements under more general conditions, and simplified the necessary calculations. According to the biographical preface mentioned above,
Bowditch vowed while writing this edition [of his navigation text] to “put down in the book nothing I can’t teach the crew,” and it is said that every member of his crew including the cook could take a lunar observation and plot the ship’s position.
After completing The American Practical Navigator, Bowditch began an English translation of Pierre Laplace’s encyclopedic Mecanique Celeste, filling in details to make the work accessible to a wider audience. He was able to translate four out of the five volumes by the end of his life.