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  • 作者: Mercer, Tony

  • 原文出版社:Robert Hale Ltd

  • 出版日期:2004/03/01

  • 語言:英文

  • ISBN:9780719803406

  • 規格:精裝 / 301頁 / 21.8 x 13.7 x 2.5 cm / 普通級

  • 出版地:美國



For many years, Tony Mercer, grandson of the most enduring English maker, has studied and collected a huge amount of information about marine chronometers, instruments which enabled explorers and the Royal Navy to map the world, the Navy to police it, and merchant venturers to sail in relative safety. The purpose of the chronometer is reviewed largely as a navigational aid for ocean-going vessels, but also for survey, medical, and other activities calling for precise time measurement. Representative examples of chronometers and deck watches by international makers--from the earliest known to contemporary instruments--are illustrated in both color and black and white. A comprehensive list of makers and craftsmen brings together details of men who worked in the industry, their places of work, and dates and serial numbers for their instruments.

Chronometer Makers of the World

The development of the chronometer is irrevocably linked to the intense rivalry and war among the British, French, Dutch and Spanish in the seventeenth and eighteenth centuries for domination of the seas to protect their trading vessels and expand their empires. Every ship's captain had the same problem: at sea, he could not establish his position within hundreds of miles to the east or west. The best solution seemed to be a clock to calculate how much the Earth had turned and thus accurately establish longitude. It would have to be as accurate on a pitching and tossing sailing ship as a precision pendulum clock on shore.

Each nation offered inducements to inventors. In 1714 the British government put up prizes totalling £45,000, worth over £2m today. The sum of £20,000 was eventually won by a Yorkshire clockmaking genius whose first trade was carpentry. Over the years that followed, marine chronometers were developed and produced in large numbers. They are all collectors' items today.

For many years Tony Mercer, grandson of the most enduring English maker, has studied and collected a huge amount of information about these remarkable instruments that enabled explorers and the Royal Navy to map the world, the Navy to police it, and merchant venturers to sail in relative safety. It would not be an exaggeration to say that the chronometer was one of the foundation stones of the British Empire. The purpose of the chronometer is reviewed largely as a navigational aid for ocean-going vessels, but also for survey, medical and other activities calling for precise time measurement.

A complete chapter is devoted to John Harrison, rightly described as maker extraordinary, giving a fascinating insight into his herculean efforts to produce a timekeeper that would satisfy all the requirements of the Commissioners of Longitude. Other great makers including John Arnold, Thomas Earnshaw, Le Roy, Berthoud, Frodsham, Dent, Kullberg and Tom Mercer are acknowledged for their evolutionary skills. Representative examples of chronometers and deck watches by international makers - from the earliest known to contemporary instruments - are illustrated in both colour and black and white.

A comprehensive list of makers and craftsmen brings together for the first time details of men who worked in the industry, their places of work and dates and serial numbers of their instruments. There is also an extensive bibliography.


I would like to express my sincere thanks to all the people and companies who have helped me in so many ways with additional information and research that have made this book possible.

These include:

Thomas Mercer Ltd., of St Albans, for their history, photographs and services; David Harries, for his knowledge of marine history and navigation; Ronald Matthews for his practical experience; Jim Connor, Pennsylvania, for his encouragement over a long period; Roger Carrington for English watchmaking history; Stel- lan Silverstolpe for Swedish history; Bill Roseman for Greenwich Observatory chronometer history; Beresford Hutchinson, Curator of the Old Royal Observatory, Greenwich; E.S. Stewart for Kelvin and Hughes' history Capt. Williams Falconer, Hong Kong; Harri, Amster- dam, Holland; J.C. Krohn, Bergen, Norway; J. Garraio, Lisbon, Portugal; Haussamann, Oslo, Norway; Martin & Co., Antwerp; Helmut Wempe, Hamburg, Germany; Iver. C. Weilbach, Copenhagen, Denmark; Observator, Rotterdam, Holland; Ets. Weizsaeker, Dunkirk, France; Hamilton Watch Co., Lancaster, USA; Ray- mond Nardin, Ulysse Nardin, Le Locle, Switzerland; Baker Lyman, New Orleans, USA; Edwin Bowers & Sons, Sydney, Australia; R.W. Whitten, Newcastle, NSW, Australia; W.R. Topham, Ontario, Canada; Unoin Relojera Suiza, Madrid, Spain;

John Griffiths, Curator, Prescot Watch & Clock Mu- seum, Prescot; Merseyside County Museum, Liverpool; Alan Trehern, University of Keele; Dr. Alun Davies, Queens University, Belfast; Richard Garnier, Chris- ties, London; Dr. D. Chapman, Liverpool University; Dr. and Mrs. Shenton, Twickenham; John Vine; Reid & Son, Newcastle; Thomas Walker, Birmingham; B. Cooke, Hull; R. Peterson, Markyate, Bedfordshire; Jill Biddle, research; All British nautical opticians; And finally my wife Priscilla, who encouraged me when my will weakened.


'Garston, ship; stranded off Starbuck Island, South Pacific, July 17, 1889. Inquiry held at Tonga, September 9, 1889. Stranding owing to chronometers putting vessel from 30 to 40 miles too far to the eastward. Master censured for not ascertaining their error. Board of Trade Official Inquiry No. 3941, 1889.

The period from the closing years of the 18th century almost to the dawn of the 21st century has seen the development, manufacture and special use of the most important form of portable timekeeper ever made-the marine chronometer.

What is it that puts the marine chronometer-or box chronometer as it is also referred to in a special category? It is because, although it works on basic horological principles whereby a highly accurate form of escapement controls the motion of the hour, minute and second hands, it is not and never has been a domestic timekeeper. It is purely a navigational instrument and, although it has tended to be replaced in recent years by very accurate electronic position-determining systems, it forms a highly essential part of the equip- ment required by the navigator on board ship for finding his exact position when out of sight of land. The other instruments used are the sextant with which the altitude above the horizon of the sun, stars, moon and planets is measured, and the Nautical Almanac, an annual publication which gives essential astronomical data, all of which is based on and measured from the Prime Meridian (0 deg. Longitude) at Greenwich Observatory, for every second of Greenwich Mean Time (GMT) throughout the year.

For safe navigation the navigator must be constantly aware of his vessel in terms of latitude and longitude: the sextant and almanac can alone provide him with his latitude, but it is only by using a chronometer, performing to such a high degree of accuracy as to provide Greeenwich Mean Time constantly to the nearest second, that he will be able to extract from the Nautical Almanac this astronomical data which ultimately enables him to compute his longitude accurately. No chronometer will ever continue to show exact GMT all the time. They will either gain or lose, but whichever of these they do, it must be as near as possible a constant amount daily and through a wide range of temperature-this amount is referred to as the 'daily rate' of that particular chronometer. Unless this is known accurately the GMT obtained from the instrument will be inaccurate, which in turn will mean that the computed longitude will be inaccurate, and this will endanger the safety of both the vessel and her crew, such as befell the Garston and many other ships over the centuries. How did the navigator manage before the introduction of the chronometer?

By measuring the altitude of the pole star or the sun when it was 'on the meridian'-when it was exactly due south or due north as the case may be and by extracting from the Nautical Almanac an entry called the sun's 'declination', he could compute his latitude to an accuracy of a tenth of a nautical mile. Because the sun's declination only changed by a very small amount hour by hour, it was not necessary to know GMT to an accuracy of an hour or two. However thereafter by allowing for every known factor such as course, speed, distance run, etc. he could only guess his longitude. When commencing a voyage he would firstly have to know the latitude of the particular place he intended to navigate towards and set course towards it. At noon every day he would obtain his latitude until he reached the appropriate latitude of his destination and would then turn east or west, as the case may be. After that, continuing daily to check that he was still on the right parallel of latitude, hopefully the place he was making for would come above the horizon directly ahead of him. This method was called Parallel Sailing'.

With the burgeoning of world trade beginning in the 18th century it was becoming obvious that the nation whose ships could determine their longitude accurately, and whose passages could therefore be run to tight sailing schedules, would attain a dominant position in world trade. This was the reason for the establishment in 1714 of the Board of Longitude, which offered a very high monetary reward to 'solve the longitude problem'. It is a well-known fact that it was John Harrison who succeeded in producing a series of four quite different chronometers, the last of which, H4, eventually gained him the reward and the title The Man Who Found Longitude'.

It is only the navigator who has had a real use for the marine chro- nometer, and possibly this is the reason that the names of their makers have received scant attention in those well-known horological publications that list many thousands of watch and clockmakers. Even less acknow- ledgement has been made to those highly skilled out-worker craftsmen who have contributed so much to its perfection. Often the only reward is a hidden framemakers' punch mark, or a scratched name on the inside of the fusee great wheel, behind the dial, or on the dial-plate itself.

Horologists and seafarers, the latter in particular, owe so much to these almost anonymous craftsmen, and it is very fitting that at long last in Chronometer Makers of the World the names of so many of them are many for the first time-being acknowledged in a specialist work.

The introduction of modern electronic navigational systems, giving a constant read-out of latitude and longitude, has led to the almost total demise worldwide of chronometer making. The wisdom of this must be in doubt because no electronic equipment is entirely foolproof, and consider ation should always be given to having an alternative back-up system available for use in an emergency.

Lieut.Commander David Harries R. N. (Retd) (Chronometer Consultant to Christies)


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