Hourglass History

Hourglasses are among a number of ingenious timekeeping devices used before the development of clocks in the Middle Ages. Hourglasses, also called sandglasses, sand timers, sand clocks, or egg timers, are a relatively recent invention.

The earliest known record of hourglasses dates from the 14th century. Hour glasses were commmonly used as timers in early factories. When working with metals the hourglass aided the tradesman in knowing when just enough heat had been applied to accomplish the desired effect.

Sand glasses were used to time thirty minute spans of time on naval ships. As each thirty minute period went by a bell was struck by hand to note the time that had passed. This was know as a watch glass.

Hourglasses were also used on ships to measure speed. This was accomplished by a crew member letting a piece of wood, or “chip log” attached to a rope with knots tied at measured intervals play into the water from the stern rail while a ship’s officer timed the action using an hourglass. This speed measurement of nautical miles came to be known as knots. The amount of time used for this measurement was merely seconds. The range of time – 14 seconds to 30 seconds - varied from one culture to another.


In the kitchen a three minute egg timer was used to let the cook know when a soft boiled egg was done whereby a ten minute egg timer was used for a hard boiled egg. The person cooking had to keep an eye on the hourglass to be able to know when the cooking task was completed unlike listening for a bell or buzzer to sound as we do today.

In 16th century England a sandglass, known as the pulpit hourglass, was used to time sermons. Imagine sitting on the hard pew, watching the glass, knowing that the preacher would not be done until the last grain of sand had passed through to the bottom. There are records of pulpit glasses measuring as much as two hours.

There is still a place for hourglasses today when one of our modern time keeping devices just will not do the trick.

Sandglasses are still used as egg timers as well as for brewing time for tea. You may use an hourglass to time a phone call. Many people use a thirty minute time glass for music practice. Just think of all of the games that use a sand timer. A twenty minute sand clock works well for meditiation periods and exercise sessions. Meetings can be kept on track by using a pair five minute or other time glasses to limit the time each person gets to speak. Hourglasses work well as teaching aids for young children who do not relate to time passed on a clock. When the sand has all run out they understand that time is done. An hourglass makes a great mind soother. Their uses are limited only by your imagination.

The pictured hourglass, made by Tom Young, is a replica of a 16th century glass found off the coast of Canada.

The jute cord on this hourglass is pulled through from one end to the other when the glass is turned. This allows the hourglass to be suspended from a hook or peg aboard ship. That helps to minimize the possible interruption in the flow of the sand that could be caused by motion of the ship.

This is one of two hourglasses made by Tom Young that are part of the collection of navigational instruments included in the Whaling Exhibit at the Basque Museum located in Boise, ID.

Public admission to the exhibit opened on Friday, July 27, 2007.

Let me know what questions you have about the history of the hourglass. If you have information that could be added to my page as well as how you use your hourglasses I would be delighted to hear from you.

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