Convert from twain to hectometer

Unit Definition (twain)
The twain is an old word for the number two, derived from the Anglo-Saxon twegen. The American author Samuel Clemens (1835-1910), who had been a riverboat pilot on the Mississippi in his youth, took his literary name from a traditional riverboat phrase "mark twain", meaning "exactly two" fathoms of water. This was the minimum depth needed for the boats to operate safely without running aground.

Unit Definition (hectometer)
A hectometre (American spelling: hectometer, symbol: hm) is a measurement of distance equal to 100 metres. This measure is rarely used and is included mostly for completeness, since usage of the SI prefix hecto is no longer recommended.