clockmaker

clockmaker

• clockmaker

• clockmaker

• watching

• watchmaker's

1 clock repairer, watch repairman.

2 watchmaker, clockmaker.

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► nombre masculino,nombre femenino

1 watchmaker, clockmaker

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- ra masculino, femenino ( de relojes - de pulsera) watchmaker; (- de pared, mesa) clockmaker

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- ra masculino, femenino ( de relojes - de pulsera) watchmaker; (- de pared, mesa) clockmaker

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(de relojes — de pulsera) watchmaker; (— de pared, mesa) clockmaker

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◊ -ra sustantivo masculino, femenino ( de relojes — de pulsera) watchmaker;

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relojero, -a nm,f

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m, relojera f watchmaker

m, Uhrmacherin f watchmaker, clockmaker, horologist altm. und geh.

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clockmaker; watchmaker

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m(f) watchmaker/clockmaker, horologist spec

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Uhrmacher m, Uhrmacherin f watchmaker, clockmaker, horologist obs und geh

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watchmaker n.

1 watchmaker's, watchmaker's shop.

2 watchmaking, clockmaking.

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► nombre femenino

1 (arte) watchmaking, clockmaking

2 (tienda) watchmaker's, jeweller's

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bomba de relojería time bomb

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1) (=tienda) watchmaker's, watchmaker's shop

2) (=arte) watchmaking, clockmaking

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femenino (tienda, taller) clockmaker's, watchmaker's; ( actividad) watchmaking

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* bomba de relojería = ticking time bomb, time bomb, accident waiting to happen, loose cannon.

* bomba de relojería + empezar la cuenta atrás = time bomb + tick away.

* mecanismo de relojería = clockwork.

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femenino (tienda, taller) clockmaker's, watchmaker's; ( actividad) watchmaking

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* bomba de relojería = ticking time bomb, time bomb, accident waiting to happen, loose cannon.

* bomba de relojería + empezar la cuenta atrás = time bomb + tick away.

* mecanismo de relojería = clockwork.

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1 (tienda, taller) clockmaker's, watchmaker's

2 (actividad) watchmaking

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relojería nf

1. [tienda] watchmaker's (shop)

2. [arte] watchmaking;

de relojería [mecanismo] clockwork;

bomba de relojería time bomb

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f watchmaker’s

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relojería nf

1) : watchmaker's shop

2) : watchmaking, clockmaking

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relojería n jeweller's

m (pl -ai) (clock- and) watch-maker

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orologiaio s.m.

1 watchmaker, clockmaker

2 ( chi ripara orologi) watch-repairer.

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pl. -ai [orolo'dʒajo, ai] sostantivo maschile (f. -a) watchmaker, clockmaker

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orologiaio

pl. -ai /orolo'dʒajo, ai/ ⇒ 18

sostantivo m.

(f. -a) watchmaker, clockmaker.

( Uhrenfachgeschäft) n watchmaker’s ( oder clockmaker’s) shop

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Uhrengeschäft (Uhrenfachgeschäft) n watchmaker’s ( oder clockmaker’s) shop

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Uhrmacher m, Uhrmacherin f watchmaker, clockmaker, horologist obs und geh

SUBJECT AREA: Horology

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Burgi entered the service of Duke William IV of Hesse in 1579 as Court Clockmaker, although he also assisted William with his astronomical observations. In 1584 he invented the cross-beat escapement which increased the accuracy of spring-driven clocks by two orders of magnitude. During the last years of the century he also worked on the development of geometrical and astronomical instruments for the Royal Observatory at Kassel.

On the death of Duke Wilhelm in 1603, and with news of his skills having reached the Holy Roman Emperor Rudolph II, in 1604 he went to Prague to become Imperial Watchmaker and to assist in the creation of a centre of scientific activity, subsequently becoming Assistant to the German astronomer, Johannes Kepler. No doubt this association led to an interest in mathematics and he made significant contributions to the concept of decimal fractions and the use of exponential notation, i.e. the use of a raised number to indicate powers of another number. It is likely that he was developing the idea of logarithms at the same time (or possibly even before) Napier, for in 1620 he made his greatest contribution to mathematics, science and, eventually, engineering, namely the publication of tables of anti-logarithms.

At Prague he continued the series of accurate clocks and instruments for astronomical measurements that he had begun to produce at Kassel. At that period clocks were very poor timekeepers since the controller, the foliot or balance, had no natural period of oscillation and was consequently dependent on the driving force. Although the force of the driving weight was constant, irregularities occurred during the transmission of the power through the train as a result of the poor shape and quality of the gearing. Burgi attempted to overcome this directly by superb craftsmanship and indirectly by using a remontoire. This device was wound at regular intervals by the main driving force and fed the power directly to the escape wheel, which impulsed the foliot. He also introduced the crossbeat escapement (a variation on the verge), which consisted of two coupled foliots that swung in opposition to each other. According to contemporary evidence his clocks produced a remarkable improvement in timekeeping, being accurate to within a minute a day. This improvement was probably a result of the use of a remontoire and the high quality of the workmanship rather than a result of the cross-beat escapement, which did not have a natural period of oscillation.

Burgi or Prague clocks, as they were known, were produced by very few other makers and were supplanted shortly afterwards by the intro-duction of the pendulum clock. Burgi also produced superb clockwork-driven celestial globes.

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See also: Briggs, Henry

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SUBJECT AREA: Horology

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Graham's father died soon after his birth, so he was raised by his brother. In 1688 he was apprenticed to the London clockmaker Henry Aske, and in 1695 he gained his freedom. He was employed as a journeyman by Tompion in 1696 and later married his niece. In 1711 he formed a partnership with Tompion and effectively ran the business in Tompion's declining years; he took over the business after Tompion died in 1713. In addition to his horological interests he also made scientific instruments, specializing in those for astronomical use. As a person, he was well respected and appears to have lived up to the epithet "Honest George Graham". He befriended John Harrison when he first went to London and lent him money to further his researches at a time when they might have conflicted with his own interests.

The two common forms of escapement in use in Graham's time, the anchor escapement for clocks and the verge escapement for watches, shared the same weakness: they interfered severely with the free oscillation of the pendulum and the balance, and thus adversely affected the timekeeping. Tompion's two frictional rest escapements, the dead-beat for clocks and the horizontal for watches, had provided a partial solution by eliminating recoil (the momentary reversal of the motion of the timepiece), but they had not been successful in practice. Around 1720 Graham produced his own much improved version of the dead-beat escapement which became a standard feature of regulator clocks, at least in Britain, until its supremacy was challenged at the end of the nineteenth century by the superior accuracy of the Riefler clock. Another feature of the regulator clock owed to Graham was the mercury compensation pendulum, which he invented in 1722 and published four years later. The bob of this pendulum contained mercury, the surface of which rose or fell with changes in temperature, compensating for the concomitant variation in the length of the pendulum rod. Graham devised his mercury pendulum after he had failed to achieve compensation by means of the difference in expansion between various metals. He then turned his attention to improving Tompion's horizontal escapement, and by 1725 the cylinder escapement existed in what was virtually its final form. From the following year he fitted this escapement to all his watches, and it was also used extensively by London makers for their precision watches. It proved to be somewhat lacking in durability, but this problem was overcome later in the century by using a ruby cylinder, notably by Abraham Louis Breguet. It was revived, in a cheaper form, by the Swiss and the French in the nineteenth century and was produced in vast quantities.

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See also: Barlow, Edward; Guillaume, Charles-Edouard

SUBJECT AREA: Horology

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Huygens was born into a cultured and privileged class. His father, Constantijn, was a poet and statesman who had wide interests. Constantijn exerted a strong influence on his son, who was educated at home until he reached the age of 16. Christiaan studied law and mathematics at Ley den University from 1645 to 1647, and continued his studies at the Collegium Arausiacum in Breda until 1649. He then lived at The Hague, where he had the means to devote his time entirely to study. In 1666 he became a Member of the Académie des Sciences in Paris and settled there until his return to The Hague in 1681. He also had a close relationship with the Royal Society and visited London on three occasions, meeting Newton on his last visit in 1689. Huygens had a wide range of interests and made significant contributions in mathematics, astronomy, optics and mechanics. He also made technical advances in optical instruments and horology.

Despite the efforts of Burgi there had been no significant improvement in the performance of ordinary clocks and watches from their inception to Huygens's time, as they were controlled by foliots or balances which had no natural period of oscillation. The pendulum appeared to offer a means of improvement as it had a natural period of oscillation that was almost independent of amplitude. Galileo Galilei had already pioneered the use of a freely suspended pendulum for timing events, but it was by no means obvious how it could be kept swinging and used to control a clock. Towards the end of his life Galileo described such a. mechanism to his son Vincenzio, who constructed a model after his father's death, although it was not completed when he himself died in 1642. This model appears to have been copied in Italy, but it had little influence on horology, partly because of the circumstances in which it was produced and possibly also because it differed radically from clocks of that period. The crucial event occurred on Christmas Day 1656 when Huygens, quite independently, succeeded in adapting an existing spring-driven table clock so that it was not only controlled by a pendulum but also kept it swinging. In the following year he was granted a privilege or patent for this clock, and several were made by the clockmaker Salomon Coster of The Hague. The use of the pendulum produced a dramatic improvement in timekeeping, reducing the daily error from minutes to seconds, but Huygens was aware that the pendulum was not truly isochronous. This error was magnified by the use of the existing verge escapement, which made the pendulum swing through a large arc. He overcame this defect very elegantly by fitting cheeks at the pendulum suspension point, progressively reducing the effective length of the pendulum as the amplitude increased. Initially the cheeks were shaped empirically, but he was later able to show that they should have a cycloidal shape. The cheeks were not adopted universally because they introduced other defects, and the problem was eventually solved more prosaically by way of new escapements which reduced the swing of the pendulum. Huygens's clocks had another innovatory feature: maintaining power, which kept the clock going while it was being wound.

Pendulums could not be used for portable timepieces, which continued to use balances despite their deficiencies. Robert Hooke was probably the first to apply a spring to the balance, but his efforts were not successful. From his work on the pendulum Huygens was well aware of the conditions necessary for isochronism in a vibrating system, and in January 1675, with a flash of inspiration, he realized that this could be achieved by controlling the oscillations of the balance with a spiral spring, an arrangement that is still used in mechanical watches. The first model was made for Huygens in Paris by the clockmaker Isaac Thuret, who attempted to appropriate the invention and patent it himself. Huygens had for many years been trying unsuccessfully to adapt the pendulum clock for use at sea (in order to determine longitude), and he hoped that a balance-spring timekeeper might be better suited for this purpose. However, he was disillusioned as its timekeeping proved to be much more susceptible to changes in temperature than that of the pendulum clock.

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SUBJECT AREA: Textiles

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John Kay was a clockmaker of Warrington. He moved to Leigh, where he helped Thomas Highs to construct his spinning machine, but lack of success made them abandon their attempts. Kay first met Richard Arkwright in March 1767 and six months later was persuaded by Arkwright to make one or more models of the roller spinning machine he had built under Highs's supervision. Kay went with Arkwright to Preston, where they continued working on the machine. Kay also went with Arkwright when he moved to Nottingham. It was around this time that he entered into an agreement with Arkwright to serve him for twenty-one years and was bound not to disclose any details of the machines. Presumably Kay helped to set up the first spinning machines at Arkwright's Nottingham mill as well as at Cromford. Despite their agreement, he seems to have left after about five years and may have disclosed the secret of Arkwright's crank and comb on the carding engine to others. Kay was later to give evidence against Arkwright during the trial of his patent in 1785.

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SUBJECT AREA: Horology, Recording

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His first connection with the phonograph principle was in the development of a miniature talking doll with a spring motor and interchangeable and indestructible celluloid cylinders in 1893 for the firm Emile Jumeau. He went on to develop commercial recording and reproducing equipment for celluloid cylinders, perfecting the process of embossing a piece of heated celluloid tube and supporting it by shrinking it onto a piece of metal tube. His training as a clockmaker enabled him to construct a functional clockwork phonograph at a time when other companies struggled with the conversion from manual or electrical to clockwork. He was unable to compete with cheap mass production and left the phonograph field in 1911. However, he continued in other acoustic fields, including moving pictures with sound and underwater sound ranging.

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1) General subject: clockmaker, horologer, horologist, watch repairer, watch-maker, watchmaker

2) Church: horologium