Gordon R. Thomas, a retired mariner and polytechnic lecturer, married with a wife Valerie and two grown up sons, writes this monograph in the pious hope that some omissions of Dava Sobel's book Longitude may be rectified.

Without detracting from the undoubted horological skills of Harrison, "The Man who Found Longitude", finding position at sea did not end with his successful chronometer, it was merely the beginning. It tool a further century of astro-navigation development, both mathematical and technical, not least of which was the almost continuous development of the Nautical Almanac without which none of Harrison's work to find longitude at sea would have prevailed.

Additionally, we must recognise the contribution of many mariners who sought to make sense of the Cosmos, scaling it's immensity to a global scale and refining the technique of celestial observation to practical application. Finally, those many instructors, teachers and lecturers who strove to impart their accumulated knowledge to future generations of navigators should be acknowledged.


- G.R. Thomas, Plymouth, 30th April 2002



Curriculum Vitae


The author went to sea in 1948 as a navigating cadet with the Royal Fleet Auxiliary Service. As second officer in the mid-1950's he found his ship some 100 miles inland in Argentina, not as a result of some gross navigational error, but carrying charter cargo of furnace fuel oil to a "frigerifico" or meat processing plant at Rosario on the river Parana. It was shortly after the death of Eva Peron and the popularity of President Peron was declining rapidly. Civil unrest and riots were to lead to a state of marshal law and the vessel was detained by customs on some dubious charge of smuggling! He could envisage another Yangtse incident developing...

Thankfully released from The Argentine and The River Plate after prolonged "negotiations", the vessel, within weeks, unexpectedly found itself investing the entrance to the Suez Canal at Port Said. With the aid of a few warships, it was expected to reclaim the canal from President Nasser of Egypt. Unfortunately, no-one had bothered to tell the ship the object of the exercise. Until then, the author thought going to sea to be adventurous enough in itself!

After ten years at sea, sailing to every major port (and many minor ones) and now with a Master's Certificate, the author left to train Merchant Navy officers. He retired from lecturing at the Institute of Marine Studies at Plymouth Polytechnic in 1990. Since then, he has followed an abiding interest in horology and Chinese porcelain.