The Sextant Handbook

by Bruce Bauer

Overview

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 navigation devices, while too convenient to disregard, are too vulnerable to rely on exclusively. The book is designed to make beginner and expert alike conversant with this most beautiful and functional of the navigator's tools. Topics include:

• Assembly and Disassembly
• Vital Adjustments
• Avoiding Problems
• Rough Weather Sightings
• Oiling and Cleaning
• Immersion Baths
• Emergency Silvering
• Finding and Buying Used Sextants
• And Much More

You'll also find a list of distributors, manufacturers, and dealers worldwide, a discussion of future trends, and numerous helpful hints, including sighting with eyeglasses and using a Rude starfinder. All in a thoroughly revised edition of a book acclaimed by navigation professionals.

Product Details

ISBN-13:	9780070052192
Publisher:	McGraw Hill LLC
Publication date:	02/01/1995
Edition description:	REV
Pages:	192
Product dimensions:	6.20(w) x 9.20(h) x 0.70(d)

About the Author

Cmdr. Bruce A. Bauer, USN (ret.), is a professional navigator and master mariner with the U.S. Merchant Marine. He presently commands a Navy research vessel sailing between the United States and the Caribbean islands and recently commanded the ship that was successful in relocating the historic sunken submarine Monitor off Cape Hatteras. A former destroyer captain, Cmdr. Bauer has taught radar and been a senior instructor for the Master Mates and Pilots School of Advanced Studies and also served as the commander of the Naval Research Lab at Chesapeake Beach, Maryland. In addition to The Sextant Handbook, Cmdr. Bauer has written articles on the subject of marine sextants for Cruising World and SAIL magazines. He lives with his artist wife, Nancy, on the shores of the Chesapeake in Deale, Maryland.

Table of Contents

Introduction

Chapter 1 A Short History

Astrolabe

Latitude Hook

Quadrant

Cross Staff

Back Staff

Sextant

Chapter 2 Elements of the Sextant and Four Vital Adjustments

Perpendicularity

Frame and Index Mirror

Frame and Horizon Glass

Parallelism

Index Mirror and Horizon Glass

Telescope and Frame

Adjustment Procedures

Chapter 3 Attachments and Accessories

Astigmatizers

Double Star Prism

Wide View Horizon Glass

Davis Prism Level

Bubble Horizon Attachment

Neck Straps

Visual Aids

Chapter 4 Care, Maintenance, and Repair

Oiling and Cleaning

Immersion Bath Procedures

How to Hold

Where to Put Down

Mounted Sextant Boxes

Emergency Silvering Techniques

Applying Paint

Resilvering Horizon Glass

Chapter 5 How to Buy a Sextant

Where to Find Them

Prices

Five Ground Rules to Avoid Problems

Taking Test Sights

Interstellar Test Table

Discovering the Dropped Sextant

Reconditioning Costs

Chapter 6 Sighting Techniques

Inversion for Location

Precalculating Azimuths

Rocking or Swinging an Arc

Sun's Upper Limb

Shades for Sun, Moon, and Venus

Correcting for False Horizon

Rough Weather Sighting Techniques

Making a Monocle

Chapter 7 Correcting the Sight

The Thirteen Errors

Correcting for Moon, Venus, and Mars

Correcting for Wave Height

Chapter 8 Timing the Sight Accurately

The Hack Watch

Using a Tape Recorder

Counting Paces and Stopwatches

Attaching Stopwatch to Sextant

Chapter 9 Searching for Stars

The Necessity for Preplanning

Finding Sunrise

Using the Rude Star Finder

Converting Local Time

Using H.O. Pub. No. 249

Making and Using a Wrist Board

Chapter 10 Sextants of Tomorrow

Is the Sextant Doomed?

Coming Developments

Appendixes

A—Sextant Check Procedures

B—Sextant Manufacturers

C—Distribution and Dealers

D—The Navigator's Basic Tool Kit

E—Making and Using an Artificial Horizon

F—Table of Interstellar Angles for Practice Sighting and Sextant Testing

G—Useful Addresses

Bibliography

Index