Convert from alen [Scandinavia] to mark twain

Unit Definition (alen [Scandinavia])
The Alen is a traditional Scandinavian unit of distance, which is very similar to the North German Elle: which is roughly equal to 2 feet or 60 centimeters.

Unit Definition (mark twain)
The mark twain or 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.