Loran and GPS notwithstanding, there will always be a place for the sextant aboard any blue-water boat, if for no other reason than the thrill and mystery of finding one's position on earth by gazing at the heavens. Here is the indispensable reference that should accompany the instrument aboard. Cmdr. Bruce Bauer, a professional navigator and master mariner with the U.S. Merchant Marine, has distilled years of hands-on experience into an eminently readable guide to buying, adjusting, using, and repairing sextants.

The Sextant Handbook is dedicated to the premise that electronic...