Danish unit

The Danes started with a system of units based on a Greek pous ("foot") of 308.4 millimetres (1.012 ft) which they picked up through trade in the late Bronze Age/early Iron Age. Some early standards of measure can be recovered from measured drawings made of the 52.5-foot-long (16.0 m) Hjortspring boat, which though dating to the early Iron Age exemplifies plank-built vessels of the late Bronze Age and the 82-foot-long (25 m) Nydam ship. Thwarts are typically spaced about 3 fod apart. From May 1, 1683, King Christian V of Denmark introduced an office to oversee weights and measures, a justervæsen, first led by Ole Rømer. The definition of the alen was set to 2 Rhine feet. Rømer later discovered that differing standards for the Rhine foot existed, and in 1698 an iron Copenhagen standard was made. A pendulum definition for the foot was first suggested by Rømer, introduced in 1820, and changed in 1835. The metric system was introduced in 1907.

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