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in fact some of these boat watches were also timing trial winners. The world's Navies realized by about 1900 that they needed rugged accurate watches for gun boats, as in gun boat diplomacy, and torpedo boats. They set up time trials for these and tested them in one posiiton and various temperatures in Geneva and especially Neuchatel. By about 1915 some of the these makers figured out the the English Teddington trial had no size limits so they started adjusting these in positions and took the top places at the English trials. The Neuchatel makers clobbered the fancy Geneva entries. Ditisheim Movado and Longines ambushed them. The ultra fine adjustment may be transitory but these are rugged relaible watches.
Also many of the finest English movement were cased in heavy silver water proof cases for explorers. These are lovely watches and they are intended to go in distant explorations with late 1800's technology. They are reliable and robust. These custoimers staked their lives on these and if they got lost, there was no GPS or radio and help was not on the way. They needed relaible longitude and these wawtches were what got them back.
Kew moved to Teddington so they are the same. Teddington was open to all so cometition was tougher so I'd prefer a winner from there. That is where the Geneva and Neuchael makers went after each other since most Geneva and Neuchatel competition were limited to locals.
All gave varous classes of certificates but the top levels foremed the competition. Thus a Kew A certicate mean that a watch met their performance standards. These systems all awarded popints for exceeding the minimum standards. Kew/Teddington published the names and data on the top 50 performaers but gave no **s. The Swiss awarded **s for individual watches groups of watches and best regulator. The Swiss certificates have a lot more informationthen Kew Teddington including who did the final adjustment. The rules and scoring were different but the top watch at Teddington had a decent claim as the best in the world.
Swiss **s were based "on a curve" If the top few watches got similar scores they all got first ** and so it went. This was probably reasonable since the differences were within the variation of the watches. If two watches were close another set ot tests might reverse the ranking.
There are enough things to like and dislike about all of them that I don't have a favorite. They did not use modern statstics so the values do not relate to modern theories of error. When they did these tests they had computers but they were humans with pen and paper and sometimes mechanical adding machines.
My favorite test is the the Allan variance which you can learn about at this link. The old Hewlett Packard (they made atomic clocks) application note is there and it's a great read. |
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