Nithsdale, William Maxwell, Earl of, a noted Catholic, who took part in the Jacobite rising of 1715, was captured at Preston, found guilty of treason, and sentenced to death; the night before the day appointed for his execution (24th February 1786) he effected an escape from the Tower by exchanging clothes with his daring and devoted countess, who had been admitted to his room; he fled to Rome, where he lived in happiness with his wife until her death (1676‒1744).
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Nisus * Nitrogen