City Clocks - Watch and Clock Repairs in London & Shrewsbury

A Brief History of Measuring Time

Asking what clocks are made for begs more questions than answers. Asking what is time, is a FAQ and probably should be addressed to Steven Hawking. Time in my experience as a Time Lord stops everything happening at once. We never have enough time so use it wisely. Without time there would be nothing. Here is how time is measured.

Clock detail - MechanismDividing the day into twenty-four hours of equal length with subdivisions of sixty minutes that are divided into sixty seconds is a comparatively new concept. With the sun rising in the east and setting in the west on a regular basis the concept of a day was not too difficult. This day divided into two periods, one dark and one light. A dark period for sleep or clubbing and a light period for work or sleep depending on your age. Light and dark periods vary in length with the seasons and are known as a natural day. While observing the natural day it was also noted that the moon would change regularly. Tweleve moons between similar seasons gave rise to a year and a natural division into twelve months. It is these divisions that may have given rise to the duodecimal counting system based on ten fingers and used by people without a calculator.

The first clock was probably just the moving shadow of a tree. Later the sundial produced the shadow. Using a sun dial in the dark periods is hopeless and it won't work on cloudy days. In some areas in the Middle Ages smog created by the coal burning industries obscured the sun. A sand-glass was of some help in the dark period but only ran for a short period of time. OK for timing an egg but not much use for timing the start of a church service. With advances in the middle ages improving glass blowing, sand-glasses started to be used by the clergy to time the length of services and time their sermons to just an hour. Sand-glasses started to get quite complex with some having four glasses timing different periods. Oil clocks, originating in Islam, became popular in the early middle ages. Useful in the dark period because they gave light as well as a measurement of time. Candle clocks appeared at this time too, marking down the candle showed the passing of time. These time measuring devices were only able to measure a period of time but could not tell what time of day it was.

Water clocks or 'Clepsydra' could measure time over a longer period and when the water wheel was invented they became much improved. The early Clepsydra or water clock from Persia and China was little more than a bucket with a hole in it. In the Middle Ages water clocks used rising or falling floats to operate a rack or a pinion to move a pointer. Water clocks became very elaborate with complications which were often a source of fascination and amusement. There are records of an early medieval water clock where figures of angels would appear every hour, bells would ring, horsemen appeared and a little man, known as jack, would strike the hour bell with a hammer. There is even a report of a water type clock run on milk, but not why. The court of Alfonso X in Castile was supposed to have a water type clock run on mercury in 1277 and is a very good example of French one upmanship. Water clocks are important because they tested mechanical components that later gave rise to the mechanical clock in the Middle Ages. Gimpel wrote, "there is no limit to the ambition and imagination of the medieval engineers and technicians, yet all their inventions, the mechanical clock is perhaps the one that symbolises their ultimate achievement".

Lewis Mumford, also writing about the importance of the clock as a symbol of the technological advance of the age wrote, "The clock, not the steam engine, is the key machine of the modern industrial age. At the very beginning of the modern technics appeared prophetically the accurate automatic machine. In its relationship to determinable qualities of energy, to standardisation, to automatic action and finally to its own special product, accurate timing the clock has been the foremost machine in modern technics and at each period has remained in the lead. It marks a perfection to which other machines aspire". A big breathrough permitting mechanical time keeping was the invention of the escapement in the 13th century. This escapement consisted of a wheel that turned with the pull of a weight. An escapement is a way of stopping and starting a wheel to slow down its motion. Ticking is the sound of a wheel being stopped and released one tooth at a time. A tooth is allowed to escape before being caught again, giving rise to the name escapement. The invention of this simple, ingenious, device marked the invention of the mechanical clock.

The word clock comes from the Latin cloca but in the monastries all types of timekeepers were known as Horologium. Monastries may have been the first places where clocks came into regular use. Monastries scattered across Europe at the time were complete communities or villages. Mills, graneries, potteries and workshops were gathered around a central church . Strictly ordered routines with seven daily and once nightly services and prayers were adhered to. Punctuality was important because it was believed that praying simultaneously enhanced the potency of prayer, hence the need for a clock. Clocks became quite common in European churches with the exception of the Greek Orthodox Church where clocks were believed to interfere with eternity and therefore banned. One of the oldest surviving church turret clocks is in Wells Cathedral and dates from 1386. The growth of urban centres in the eleventh century led to a busy town like that was ordered very differently to the natural day of the peasant. People needed to arrive at work at a specific time. Shipping relied on high tides to dock and the merchants needed to predict those tides for loading and unloading ships. Towns and villages competed with one another to own the best clock.

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The city of Prague commissioned a clock so wonderful that hundreds of people came to see it and brought trade to the town. To prevent the clockmaker building such a clock for another town his eys were put out. Quite a drastc way of enforcing a contract. Clockmakers skills attracted the attention of the rich and royal who as patrons of the clockmakers encouraged the development over the next four hundred years of clocks that became precise, portable and so accurate that a clock on board a ship could determine longitude and allow exploration and exploitation of the world. Harrison was the man who invented such an accurate clock, so now you know whom to blame. Without very accurate clocks we would not have the benefit of cruise missiles! or much more useful, the satnav. Clocks and clockmakers have been very important. Look after your clockmaker.

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