![]() At the very least I would advise carrying a sextant, even a cheap one. If you want to know your proper position, and most of us do, and there is no GPS, I can see no alternative to some rudimentary knowledge of astro navigation. But hey, if you’re crossing the Atlantic, for instance, you are bound to hit something the far side, just like Christopher Columbus, while the Vikings are thought to have employed a crude form of astro anyway. I believe it’s called dead reckoning, perhaps with the emphasis on ‘dead’ as the longer that goes on the less accurate your estimated position will be. However, out in the oceans this is no good at all, except insofar as you can keep a detailed log of courses steered from your last proper fix, at what speed and for how long (to gauge distance run) and plot this daily on your chart. Or there are a lot of clever running fixes from just one mark and back-bearing ably described by Tom Cunliffe in his many books on navigation, with a mine of related information in Malcolm Pearson’s Reeds Skipper’s Handbook. Ideally you would have two or three identifiable marks with back-bearings, to form a cocked hat or triangle with you in the middle. If you are coastal or offshore sailing and can observe any identifiable land or sea mark then, as you will know, you can take a bearing with a handheld compass, work out the back-bearing (plus or minus 1800) and plot it on your paper chart. But the greatest feat of navigation was achieved by the Polynesians who sailed the mighty Pacific mainly by reading the stars. And, while compasses and sextants were developed over time, the bulk of early navigation was done by observation, say, by watching swells and currents, flights of birds, cloud formations and so on. Well, there was no GPS thousands of years ago when the first sailors set out on seagoing reed boats. We have become so dependent upon GPS for navigating our voyages whether coastal, offshore or round the world, what would we do if we were suddenly left bereft? Now that is a question to concentrate the mind (writes Rev. ![]() ‘What would you do if you lost GPS – how would you navigate?’
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