In the tradition of Dava Sobel's ‘Longitude’ comes sailing expert David Barrie's compelling and dramatic tale of invention and discovery – an eloquent elegy to one of the most important navigational instruments ever created, and the daring mariners who used it to explore, conquer, and map the world.

This is the dramatic story of an instrument that changed history. Built around David Barrie’s own transatlantic passage using the very same navigational tools as Captain Cook, Sextant tells how one of the most vital navigational instruments was invented and used – and why the golden age of celestial navigation has now come to an end. From Cook, Bligh and Vancouver to Bougainville, La Pérouse, Flinders and FitzRoy, Barrie recounts the fortunes of the explorers who risked their lives in charting the Pacific, as well as the intrepid adventures of Slocum, Shackleton and Worsley. A heady mix of history, science and adventure, this elegy to a lost technology is infused with the wonder of discovery and the sublimity of the cosmos.