The
Danes started with a system of units based on a Greek
pous ("foot") of 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
Hjortspring boat, which though dating to the early Iron Age exemplifies plank-built vessels of the late Bronze Age and the
Nydam ship. Thwarts are typically spaced about 3
fod apart. King
Christian V of Denmark introduced an office to oversee weights and measures, a
justervæsen. This was first led by the royal mathematician
Ole Rømer, who established a national system of weights and measures on May 1, 1683. Rømer's system, which he updated in 1698, was based on the Rhine foot. Its definitions included the following: • the Danish mile as 24,000 Rhineland feet (i.e. 4 minutes of arc latitude) • the Danish pound (
pund) as of the weight of a cubic Rhineland foot of water (499.7 g) • the Danish ell (
alen) as 2 Rhineland feet (630 mm) Rømer also suggested a pendulum definition for the foot (although this would not be implemented until after his death), and invented an early temperature scale. The metric system was introduced in 1907. ==Length==