Livre en anglais par J.H. Francis Wadsworth
Reprint from Antiquarian Horology
16 pages, 14 photos.
MAN must always have wanted to know the time during the hours of darkness, this was first achieved by the use of clepsydra, sand-glass, etc., to record the hours since sunset. With the invention of the mechanical clock time could be told by waiting for the next hour to be struck. When domestic clocks were introduced the position of the hand could be felt. It was natural that when the watch was first made in about 1500 the owners of these new time-keepers should also want to know the time in the dark.
As these watches, like the clocks of the period, were controlled by a balance without a spring, they did not keep time very well and had only one hand, so it was possible for the time at night to be felt. To assist the estimation of the time, the early watches had small knobs at the chapters on the dial, similar to the ones on the clocks of the time.
This was quite satisfactory until watches kept better time with the invention of the balance spring in about 1675. With the improved time-keeping, a second concentric hand was added to show the minutes, and this hand was too delicate for feeling the time. The application of the pendulum in 1657 to clocks had brought about a similar situation, which was also overcome about 1675 by the invention of a mechanism which, on pulling a string, would strike the last hour and quarter on bells. This mechanism is called repeating work.
It is not surprising that the watchmakers of the day should attempt to make repeating watches. Where and by whom repeating work was first applied to watches is impossible to say, but it would not be surprising if watchmakers had adapted clock repeating work to watches before a special watch work had been evolved. The invention of special watch repeating work took place in London in about 1687, when both Thomas Tompion and Daniel Quare produced repeating watches. The delay between the invention of clock repeating work and its application to watches was most probably due to the difficulty in producing a satisfactory watch with a balance spring, also to the smallness of the repeating work required.
After 1687 the making of repeating watches spread throughout the watchmaking world, and by 1730 three types of mechanism had developed. Watches by then repeated the hours and quarters, some the half quarters, and some the five minutes. About 1830 a new type of repeater became common, that was the minute repeater, which struck the time to the last minute.
The big disadvantage of the repeating watch was that it was complicated and costly to make. Watchmakers had, since the beginning, tried to make cheap repeating watches but had never succeeded in popularising them. From the middle of the 19th century repeating watches were made by machinery in Switzerland, but even this did not make them popular or cheap.
The demand for cheap watches grew during the latter part of the 19th century and so did the demand for some cheap method of telling the time at night. About 1880 a luminous powder was discovered. This had the disadvantage that it had to be periodically exposed to light for its luminous qualities to be maintained. As most watches were kept in the pocket the luminous qualities had little chance to be induced, and so its use on watch dials was a failure. The discovery in 1898 of radium was quickly followed by the observation that radium gave a luminous quality to zinc blende. The use of this permanent luminous material made reliable luminous dials possible.
The 1939-45 war finally put a stop to the commercial manufacture of repeating watches, and although one never knows what the future has in store, at present the history of repeating watches stretches from 1685 to 1940, In these 255 years the need for telling the time in the dark has not disappeared, but the means of doing so has completely changed. No longer is it necessary to rely on the sound produced by an expensive mechanism, the simple luminous dial makes it possible to read the time in the dark.
This does not mean that the repeating watch is useless, for blind people use them and I am sure will do so for many years to come.
The following is intended as a general history of repeating watch work during 255 years of manufacture, and is only a small study of a very extensive subject.