The latest edition of the Bowditch. The American Practical Navigator, first published in 1802, was billed as the "epitome of navigation" by its original author, Nathaniel Bowditch. The text has evolved with the advances in navigation practices since that first issue and continues to serve as a valuable reference for marine navigation in the modern day. The publication describes in detail the principles and factors of navigation, including piloting, electronic navigation, celestial navigation, mathematics, safety, oceanography and meterology. It also contains various tables used in typical navigational calculations and solutions, including the formulas used to derive the tabular data. - NGA