Customer Reviews

Taking the Stars: Celestial Navigation from Argonauts to Astronauts

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Today the very idea of using a sextant seems crazy when you can just switch on your GPS and be told where on the planet you are. This book takes you through some of the scientific instruments used to find your position on the earth. The author has taken the time not only to display excellent photos of the instruments but also describes their use. If you have an interest in either astronomy, celestial navigation or even scientific instruments I cannot recommend this book highly enough.

I have spent days savoring this delicious work. Ifland has set a new standard against which all subsequent instrument books must be judged. The illustrations are magnificent; the text is lucid and I particularly like the fact that, in many cases, instructions are given for actual use of the instrument being discussed. Thank you, Peter Ifland!

There are a few books on instruments used for nautical astronomy that you must have if you are interested in this field: Mörzer Bruijns "The Cross Staff", Stimson " The Mariner`s Astrolabe", Albuquerque "Instruments of Navigation" and Cotter "A History of the Navigator`s Sextant". This last book - although full of facts - is sadly lacking in good illustrations. "Taking the Stars" has both: a thorough and detailed history of instruments used for making astronomical observations right up to the latest developments and beautiful illustrations that show in detail what the text is talking about. It is rather rare that one finds such a well informed text in a book which can easily pass as a "coffee table book". My first copy of this book was destroyed by water; I ordered a new copy the next day.

Centuries ago, Arab (or perhaps Chinese) mariners began using an instrument to help find their latitude, called a kamal (or in Chinese chhien hsing pan), which was nothing more complicated than a credit card-sized rectangle of wood or ivory.

The navigator held the kamal before him so that the bottom edge rested on the horizon and the top edge on a star. A string came out of the center of one of the flat sides of the card. The mariner took the string in his teeth and tied a knot to mark how far out he had to hold his kamal.

Meanwhile, Pacific Islanders were using a more sophisticated system, but one with less potential for improvement.

Trying to measure the angle of a star (or sun or moon) from a rolling deck was tricky, all the more so when it involved staring directly into the sun. The big breakthrough came in 1731 when an Englishman, John Hadley, proposed a "double reflecting" arrangement that used mirrors to bring the horizon together with the celestial target.

There followed some of the most beautifulo and efficient machines ever devised. Scores of them are pictured, most in color, in "Taking the Stars."

The book is co-published by The Mariners' Museum at Newport News, Va., where author Peter Ifland has donated his large collection.

In many ways, sextants (the favorite form of Hadley's invention) were the key instruments in the evolution of modern life.

A sextant had to resist corrosion, be strong and light and have extremely accurate measuring marks. Jesse Ramsden achieved fame with his "dividing engine" for marking the degrees of a circle, and his engine was then turned to a multitude of varieties of precision machine work for the Age of Industry.

No fundamental change was made until the invention of an artificial horizon, for use when the real horizon was obscured. (This was usually the case on land, where -- unlike Polynesian navigating techniques -- the mariner's system was readily adapted.)

Sextants and their relatives maintained a grace and style even as they acquired a variety of gizmos and trick devices, but by the 20th century the combination of utility and beauty was about to be broken.

Part was due to aviation, which required even more rapid calculations, and part to practicality -- the beautiful lines of the frames either were enclosed in (usually) black crackle plates or eliminated by use of prisms.

Plus, the sextants acquired awkward looking gyroscopes and counters. Where once their function was open to any inquiring eye, by World War II most sextants were truly black boxes to the uninitiated.

"Although not nearly as photogenic as the beautiful old brass seagoing sextants," writes Ifland, "the modern aircraft sextant fits nicely in the hand, provides a stable mounting for the optical system and is easy to store and use in the confined spaces of an aircraft."

Just so, but visitors to The Mariners' Museum probably will linger longer over the ancient tools.

It's all history now. First, land-bases radio guidance systems began superseding star and sun sights. Though recreational sailors still shoot the sun, sometimes with inexpensive but fairly accurate plastic devices, professionals are becoming dependent on satellite-based geographic positioning systems.

In 1999, the Naval Academy stopped teaching celestial navigation after 143 years.

Although not cheap this book is worth every penny to anyone interested in the history of navigation and the navigators instruments themselves. lavishly illustrated with colour photographs and drawings the text is authorative and leaves little of the subject un covered.