Contest Directions: Photoshop this hourglass image (click to download) any way you wish. Some examples are: reshaping the hourglass, merging it with other objects or animals, putting the hourglass into some unusual environment, using this hourglass image in advertisements, movies, paintings, etc. These are just some ideas.
Many thanks to Satendra Mhatre and
Stock Exchange for providing the source photo.
RICKYTREK1 from a broken hourglass time is running very slowly, crawling like a baby ... but no matter ... another child and 'ready to take his place ...... and then another ... another ..... another ............
Register to post comments and participate in contests.
This contest is fueled by the following news: Hourglass is a simple device for calculating time intervals and consists of two vessels connected by narrow neck, one of which is partially filled with sand. Time, during which the sand flows through the neck to transfer into another container, may range from several seconds to several hours.
Hourglasses are famous since ancient times. In Europe, they spread widely during Middle Ages. Ships used four-hour hourglass (time of single watch) and 30-second hour glasses to determine the speed of ship on log.
Presently, the hourglass is used only during certain medical procedures, photos & also as souvenir.
In Microsoft Windows operating system, the hourglass symbol is used to indicate that the mouse cursor is busy.
The size of hourglass is not always determining factor for bleeding cycle of sand. However, if this cycle is of few days, then the number of hours must be really more.
Two such giants exist - "TimeWheel" in Budapest (capital of Hungary) & in (dead link - history) Sand Museum in Japanese city of Nima. "With height of eight & six meters long & bleeding cycle of one year, they are the biggest the time measuring devices in the world. Another giant, from July 2008, stands at Red Square in Moscow. At height of 11.90 m & weight of 40 tons, it is probably the world's biggest hourglass. Both glasses of hourglass are so huge that, they can almost accommodate BMW of 5-meter length. In contrast, the world's smallest hourglass is only 2.4 cm high. It was made in 1992 in Hamburg & transfers entire sand from upper chamber to lower in less than 5 seconds.
Hourglass was invented in ancient times & became widespread in Europe during the Middle Ages. It seems that, this elementary device, even now is not just an antique piece, but is also used in some intended applications.
Like fire, the hourglass never reached the accuracy of sundial. In addition to this, on prolonged use of such clocks, their accuracy varied as grains of sand gradually split into more fine pieces & the hole in the middle of diaphragm gradually increased due to wear & tear, so that the rate of passage of sand through them became greater.
No matter how unusual it seems, the hourglass was used almost at the same time as the first mechanical clocks & their term of existence is only about seven hundred years.
Of course, the hourglass are relatives of water clocks, as both depend on material / fluid passing through the hole. However, the hourglass has its own technological features. On the positive side, they are much simpler & cheaper than mechanical watches or more primitive water clocks. It is possible to restart once entire sand is poured into the lower part, can not be more simpler - it is enough to flip it. The material - sand is not consumed here as in the case of candle clocks. They also ensure good accuracy - if some details are not neglected during their production. You cannot just use any old sand in them, it is necessary to select friable material, which does not absorb water from the air & does not become moist.
Initially, hourglass was used as timer in factories in early years. While working with metal hourglass, which could be bought for a decent amount, it helped employees to know when to achieve desired effect of sufficient fire.
Hourglass (it was never mentioned in history) was used to determine the time in naval ships; it was connected to a bell, which rang after the completion of half an hour. Hourglasses were also used on ships to measure speed. Rope with knots, was tied at a certain distance was dropped into waters from stern & officer of the ship determined the speed using sundial. Such measurement of speed had lent the name Nautical miles - knots.
And, where were the small hourglasses used (many housewives preferred hourglasses to timers) - mainly, in kitchen, for example, to determine when an egg is cooked soft boiled or hard boiled. To be true, it was not very convenient since it was mandatory to keep a vigil on hourglass while modern timers indicate the time by issuing an alarm.
In the 16 century in England, hourglasses were used to determine the duration of sermon. Imagine, how much attention was drawn towards the hourglasses by people sitting on hard uncomfortable chairs, knowing that the preacher will not finish speaking till the last grain of sand falls into the lower part.
Disadvantages of hourglass:
With regard to work, the hourglass is a short duration clock. It is very rare that such a model works for more than 1 hour. Another big drawback is that, it is not possible to determine time accurately, i.e. Hourglass - which today can be bought in an antique shop work in fits and starts. You can determine the e end of time period but not more than that. If you make a mark on the glass, sand will reach the mark each time at different times.
Here are some factors that affect the accuracy of hourglass:
* Quantity and volume of sand particles;
* Size & angle of glass bowls;
* Quality of sand or granular materials. They should be tiny, dry & form smooth flow (fine-grained sand, crushed marble etc. was used in the past);
* Size of the hole;
Leak-proof of the shape, which does not allow moisture inside, makes the material heavier & can clog the hole;
We still use the hourglass – its sphere of usage is very broad, from decorative piece to a replacement of timer in kitchen.