- Buy this product and stream 90 days of Amazon Music Unlimited for free. E-mail after purchase. Conditions apply. Learn more
Reed's Sextant Simplified Paperback – 31 Mar 2003
- Choose from over 13,000 locations across the UK
- Prime members get unlimited deliveries at no additional cost
- Find your preferred location and add it to your address book
- Dispatch to this address when you check out
Special offers and product promotions
Frequently bought together
Customers who viewed this item also viewed
Enter your mobile number or email address below and we'll send you a link to download the free Kindle App. Then you can start reading Kindle books on your smartphone, tablet, or computer - no Kindle device required.
To get the free app, enter your mobile phone number.
About the Author
Dag Pike began his career as a merchant captain, went on to test RNLI lifeboats, and took up fast boat navigation, winning a string of trophies for powerboat races around the world, including navigating Richard Branson's Virgin Atlantic Challenger on the record-breaking fastest Atlantic Crossing by powerboat. He is now a navigation and powerboat journalist in demand all round the world.
Customers who bought this item also bought
There was a problem filtering reviews right now. Please try again later.
Most helpful customer reviews on Amazon.com
The use of the sextant in navigation is not included. This is truly a simplified text and may be a beginners first exposure. It could have been more structured so that a beginner could walk through examples of use. Instead it tries to discuss most details in a running text.
The discussion could have profited by several good examples of a sextant in use. I have used my great grandfather's sextant for years and have designed star-trackers for various space missions and picked up most of the knowledge on the fly. This book helps, but it could have been better.
The sextant, of course, is employed to measure angles between objects, especially the angular distance of heavenly bodies above the horizon. A single sighting of Polaris, together with a copy of the Nautical Almanac, can give one the latitude outright. Of course, that only works at night (with Polaris not covered by a cloud), and one has to be at least a couple of degrees into the Northern hemisphere to see Polaris. And a sighting of the Sun as it goes through high noon (once again, this works only if the Sun is visible then) also gives one the latitude directly, using that Nautical Almanac. Used in conjunction with an accurate timepiece, it also gives the longitude.
While Pike does not give advice on what to do with the information you get to, say, plot your position on a chart, he does give advice on how to deal with the problems of taking sights on a moving boat. This is by no means an easy task!
This is a fine book, but I wish to comment on the following topic: is a sextant still that useful an instrument in ocean navigation?
Can one navigate without a sextant? Of course: all one needs is a working GPS system. Of course, if one's GPS isn't working, it's not a bad idea to have a sextant as a backup.
Can one navigate with a sextant but without the Nautical Almanac (or an equivalent, such as Bennett's less precise "Celestial Navigator")? Well, yes. A simple program such as "Pocket Stars" will fit on one's PDA and can be used to do the calculations. Of course, that won't help much if your PDA runs out of power.
Can one navigate lacking both GPS and a sextant? That's not so easy. Captain Bligh had to do that when he was denied a sextant after he and some of his men were evicted from the Bounty by the mutineers. And he did a terrific job of it with an improvised but rough angle-measuring device. Even without such equipment, one can use "dead reckoning," which means estimating "course made good," hopefully with the aid of a compass. And you can also get some very useful information by taking sun sights at sunrise or sunset (no sextant is needed for these, but the variation errors due to the atmosphere can be rather significant).
I think this puts the utility of a sextant in perspective. It can be used to determine one's latitude to well within a mile, and it is really useful if your GPS is not available.