The American Practical Navigator, after over 100 years, sells around 300 a month in peace times, and as much as 15,000 in war times -- a perpetual best seller that is never listed! It is known as the ""seaman's bible"" and its mathematically minded editor's life, while neither colorful or dramatic or of great human interest, reveals a directness of purpose and study that is unique. Self educated, he went from a ship chandler clerkship to supercargo aboard ships for foreign ports at war. He was interested only in observations for positions, charts, and the practical sides of navigation and worked steadily on revision of Moore's Practical Navigator, which in 1802 bore Bowditch's name. This records his personal ventures in shipping, his travels, his further writings, his marine insurance business, his work as consultant. He work and fame were his life, an important segment of American maritime history. A spry little man, whose career one must relish.