Chinese sailors were using magnetic needles floating in bowls of water by the
4th century, A.D., and European sailors were using compasses of this sort by
1200. Compasses consisting of a magnetic needle balanced on a pin can into use
soon thereafter. The fact that "compass maker" was a profession in
Nuremberg from the mid-1480s indicates the growing importance of these
instruments. Simple pocket compasses were probably made at an early date, but
the earliest known examples are complex instruments that combine a compass with
a small dial of some sort.
