The mechanical clock was invented in the Middle Ages. Who made the first one and when is not known but it was around the end of the 13th century. In 1309 a clock is recorded in a church in Italy. The oldest working clock in the world is in Salisbury Cathedral. It dates from 1386 and it has no dial. Instead it chimes the hours. (Our word clock comes from the Latin word for bell 'clocca').
Early clocks were normally in churches and they were very heavy because they were worked by weights. However about 1450 the coiled spring was invented and it made possible portable clocks. The first watches were made in 1510. In the 16th century some rich people had clocks in their homes but they were very expensive.
Early clocks were not very accurate but in 1657 Christiaan Huygens introduced the pendulum. Clocks became far more accurate though they were still set using sundials.
In the late 17th clocks with long cases were made. In 1876 a man named Henry Clay Work wrote a song called My Grandfathers Clock and in the early 20th century they became known as Grandfather clocks. Meanwhile the cuckoo clock was invented c. 1775. The stopwatch was invented in 1776 and the electric clock was invented in 1840. The quartz crystal clock was invented in 1929 and the atomic clock was invented in 1955.
In Britain each town had its own time and it was not standardized until the 1840s with the coming of the railways. International time zones including Greenwich Meantime were formed in 1884.
Watches were very bulky until c.1675 when the spiral hairspring was invented and modern pocket watches evolved. The electric watch was introduced in 1957 and the quartz crystal watch was introduced in 1967.
However sundials were used long after clocks were invented. In the Middle Ages and the 16th century, many people carried pocket sundials. Several pocket sundials were found on the Mary Rose, which sank in 1545. Shakespeare mentioned a sundial in his play As You Like It: 'and then he drew a dial from his poke'. (A poke was a bag).
Even in the 18th century clocks were a luxury. In 1726 Lady Farringdon added clocks to Chichester Market Cross. At the time they were very expensive and it was a very generous act.
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