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One account says that the word "watch" came from the Old English word woecce which meant "watchman", because it was used by town watchmen to keep track of their shifts at work.
Drawing of one of his first balance springs, attached to a balance wheel, by Christiaan Huygens, published in his letter in the Journal des Sçavants of 25 February 1675.
The application of the spiral balance spring (spiral hairspring) for watches ushered in a new era of accuracy for portable timekeepers, similar to that which the pendulum had introduced for clocks.
A great leap forward in accuracy occurred in 1657 with the addition of the balance spring to the balance wheel, an invention disputed both at the time and ever since between Robert Hooke and Christiaan Huygens.
This innovation increased watches' accuracy enormously, reducing error from perhaps several hours per day resulting in the addition of the minute hand to the face from around 1680 in Britain and 1700 in France.
The increased accuracy of the balance wheel focused attention on errors caused by other parts of the movement, igniting a two-century wave of watchmaking innovation. The verge escapement was replaced in quality watches by the cylinder escapement, invented by Thomas Tompion in 1695 and further developed by George Graham in the 1720s.
The lever escapement was the single most important technological breakthrough, and was invented by Thomas Mudge in 1759 and improved by Josiah Emery in 1785, although it only gradually came into use from about 1800 onwards, chiefly in Britain.
Although there was an attempt to modernise clock manufacture with mass production techniques and the application of duplicating tools and machinery by the British Watch Company in 1843, it was in the United States that this system took off.
A pocket watch is designed for a person to carry in a pocket.
Elizabeth I of England received a wristwatch from Robert Dudley in 1571, described as an armed watch.
The oldest surviving wristwatch (then described as a bracelet watch) is one made in 1806 and given to Joséphine de Beauharnais.
Aaron Lufkin Dennison started a factory in 1851 in Massachusetts that used interchangeable parts, and by 1861 it was running a successful enterprise incorporated as the Waltham Watch Company.
The concept of the wristwatch goes back to the production of the very earliest watches in the 16th century.