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Length calibrator used in the Japanese colonization period (one meter)

“Meter prototype” is a standard instrument used to measure length in the metric system. Its purpose is to ensure that the units of length can be measured correctly. Taking the Earth as a standard, the meter was originally defined as one ten-millionth of the distance between the North Pole and the equator at the longitude of Paris. Then, the “International Meter Prototype” made of an alloy of platinum and iridium, was constructed accordingly. There are many duplicates of the original meter p rototype. The one currently collected by the National Science and Technology Museum was received by the Taiwan Provincial Institute of Weights and Measures from Japan, and was donated to the Museum in 2001.

However, along with the development of science and technology, the length of the meter was redefined. The more precise definition now states that the meter is the length of the path traveled by light in vacuum during a time interval of 1/299,792,458 of a second. Even though the meter prototype is no longer used today, it represents the transition of units of length in the metric system.

In order to decrease metal expansion and contraction resulting from temperature fluctuations, the meter prototype was made as an X-shaped form in order to reduce inaccuracy.

The 5-cm scale on this memento was carved for a practical purpose. The scales on the original prototype meter bar were carved at both ends with a distance of one meter in between.

L:102.00 cm X W:0.00 cm X H:0.00 cm

Metrology