Convert from verst to mark twain

Unit Definition (verst)
An obsolete Russian unit of length. It is defined as being 500 sazhen long, which makes a verst equal to 3500 feet (1066.8 metres).

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.