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“Hourglass, also called sand timer hourglass, a device for measuring time. In its usual form it consists of two cone-shaped or oval glass receptacles joined by a narrow neck. Sand or a liquid (such as water or mercury) in the uppermost section of a true hourglass will run through the neck into the lower section in exactly one hour. By turning the other end up, another hour may be marked, and the process may be continued indefinitely. When sand is used, the device is sometimes called a sandglass. A small sandglass, in which the sand passes from top to bottom in three minutes, is used for timing the boiling of eggs. An early instrument working on the same principle was the clepsydra, or water clock.
Hourglass clocks are probably the most recognizable ancient clocks out there. They have been featured in a lot of scenes of a lot of movies and TV shows. Often when the director wants to create a dramatic sense of emergency they are used.
Hourglass clocks were one of the very ancient clocks that we as humans made in our evolution in getting more accurate time. Humanity took centuries to stumble upon viewing time the way we do nowadays. When humanity was still a bit young we used to mark time by the rising and setting of the sun. And a month by the waxing and waning of the moon. But as we grew we built better and more precise ways of telling time. And, one of our earlier tries to this was “”The Hourglass clock””.
Some History
As we said in the previous paragraph, there is no record of their being an hourglass in Europe before the Early Middle Ages. And the very first hourglass is said to have been made by a french monk named Liutprand during the eighth century A.D. But it wasn’t until the 14th century that Hourglass clocks were seen more commonly.
They started off being popularly used in Marine Voyages at the start. One of the earliest recorded references to a marine glass was in 1345, noted by Thomas de Stetesham. He said “”The same Thomas accounts to have paid at Lescluse, in Flanders, for twelve glass hourglass, price of each 4? gross’, in sterling 9s. Item, For four hourglass of the same sort, bought there, the price of each five gross’, making in sterling 3s. 4d.””
Hourglasses were rather quite popular on ships as they were considered a very reliable way of measuring time while traveling at sea. It proved to be quite an improvement from the water clock ( the predecessor of the hourglass clock ), as the motion of the water didn’t affect the hourglass while sailing. As it used to in the water clock. Moreover, the fact that the hourglass used granular material instead of water made it even more accurate. The water clock often got weirded out as temperature changed and condensation played its part. Not only this but the seafarers also found that the hourglass clock was able to help in the determination of distances from a point, as well as longitudes.
Design of the Hourglass clock
This clock uses two separate bulbs with a granular material inside and an opening connecting the two bulbs. This means that the granular material/ sand would fall down on the bulb down below due to the mere effect of gravity. However, there have been variations in hourglasses too that were made over time. For instance, though hourglass clocks have always been in ampoule shape, their bulbs were not always connected. The first hourglasses that were used had two separate bulbs with a cord wrapped at where they met. This cord was then coated in wax to hold the piece together and let sand flow in between. It was only after 1760 that these clocks were actually ever blown together to help keep the moisture out of the bulbs and regulate it with fair pressure
Nowadays, hourglass has been designed into many different types with different materials such as wood sand timer or wood hourglass, plastic sand timer, metal sand timer or metal hourglass, acrylic sand timer, glass sand timer, acrylic timer, etc.
