The History of the Sextant - Transcript of a talk given at the Science Museum of The University of Coimbra. Includes photos of ancient devices. Secrets of Ancient Navigation - An overview from the PBS show "The Search for Longitude". The History of the Sextant - The evolution from the earliest instruments to the sophisticated devices used today described and illustrated. Understanding How Thompson Navigated - About David Thompson's exploration of western Canada and the northwestern United States from 1790 to 1812, using a sextant and compass. From the Northwest Journal. Evolution of the Sextant - Illustrated article including details about dating. Links to antique instruments offered for sale. Escape from Antarctica - Recreates the navigation Ernest Shackleton's crew used on their voyage seeking rescue. Longitude at Sea - Describes 17th and 18th century use of eclipses of Jupiter's moons to identify position.