Hourglass timers has been around since the 15th century first, by trial and error, water has been used to try to control time intervals. However, water is not a good source of time because of their inability to be precise and regulated since it came into contact with heat, cold, weather, or movement. dry sand does not change the speed on impact or sitting in the sun for hours. Everything concerning the weather, heat, cold or movement changes the flow of sand, while the interior glass ampoules.
Hourglass timers consist of two glass bulbs which are connected by a narrow tube, allowing the sand to pass from one container to another. Depending on factors such as the quality of the sand, the size of the lamp, the passage width and the amount of sand used determines the amount of "time" is maintained. For example, hourglass hourglasses only keep the 3-5 minute time intervals. sand substitutes may be an oil / water mix that is more common in current versions of the product. Another material used is powder of eggshell and marble powder. In general, a large frame are independent wood, chrome or brass and are vertical loops on the sides. hourglass timers are known to be the time keepers, but also part of important collections. The average cost of a modern hourglass is about US $ 25. However, older antiques can cost hundreds or even thousands of dollars.