An excellent navigation text for either the navigator who knows the rudiments and wants to learn about the whys and wherefores or for the studious beginner who wants to learn not only how to navigate, but also the geometrical background of celestial navigation. And each chapter has interesting notes on the lore of navigation. In any case, this book can teach you to navigate using time, the sextant, the Nautical Almanac, and a hand calculator with trigonometric functions, the latter eliminating the need for sight reduction tables, although they are by no means abandoned from his instructions. This is an outstanding book that can convert your navigation from the perfunctory to the fascinating.