Longitude At Sea
The Meridian Problem
Leap Year Compliance
The Millennium Bug


On Navigation At Sea


A series of monographs by Gordon Thomas, my father.

These were written early in 1999, when the coming Millennium and the fall of civilization that some predicted would follow had turned the media's attention to the whole issue of time and date. The "Longitude Problem" featured in an award-winning book (and it's acclaimed television adaptation), Dava Sorbel's Longitude, the story of the eighteenth century watchmaker Thomas Harrison's life-long obsession with building an accurate marine chronometer to enable longitude to be calculated at sea. While I know that my father enjoyed the book, he was convinced that the author, and the media in general, had missed an important part of the problem - even though an accurate record of time could now be kept at sea, there were still major difficulties involved in actually using this information, and much work still remained to be done before the process of maritime navigation reached it's zenith in the twentieth century...


"I have read several books and watched recent T.V. programmes on the LONGITUDE AT SEA problem and I am growing more and more amazed how little is apparently known - even by the so-called experts. In twenty-five years the art of celestial navigation, "Astro-Nav", will virtually be forgotten, recalled only by a tedious trawling through a few specialist, out-of-print textbooks - and who will bother? I doubt that even ship's officers in training now are taught much of the principles involved since satellite navigation systems - the SATNAV or NAVSTAR Global Positioning Systems - have ousted the sextant and chronometer in regular use.

Accordingly, I intend burdening you with my knowledge, gained over the past fifty years, in a series of monographs. If it appeals, you will at least have the chance to record it for posterity! A millennium equivalent of Pepy's Diaries without the disadvantage of having to decode the text!

Here goes."


Author's Introduction

Finding Longitude At Sea

The Meridian-Altitude Problem

Leap Year Compliance Syndrome

The Leap Year And The Millennium Calendar Bug

About the Author



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