It is necessary to dwell at some length on this conception of "a fleet in being." Admiral Mahan, the great historian of sea power--whose high authority all students of naval warfare will readily acknowledge and rarely attempt to dispute--speaks of it in his _Life of Nelson_ as a doctrine or opinion which "has received extreme expression ... and apparently undergone extreme misconception." On the other hand, Admiral Sir Cyprian Bridge tells us in the _Encyclopædia Britannica_ (_s.v._ "Sea-Power") that "the principle of the 'fleet in being' lies at the bottom of all sound strategy." Of a principle which, according to one high authority, lies at the bottom of all sound strategy, and according to another has received extreme expression and undergone misconception equally extreme, it is plainly essential that a true conception should be obtained before it can be applied to the elucidation of any of the problems of naval warfare. Now what is this much-debated principle? It is best to go to the fountain-head for its elucidation. The phrase "a fleet in being" was first used by Arthur Herbert, Earl of Torrington, in his defence before the Court Martial which tried and acquitted him for his conduct of the naval campaign of 1690, and especially of the Battle of Beachy Head, which was the leading event--none too glorious for British arms--of that campaign. "Both as a strategist and as a tactician," says Admiral Bridge, "Torrington was immeasurably ahead of his contemporaries. The only English admirals who can be placed above him are Hawke and Nelson." Yet he was regarded by many of his contemporaries, and has been represented by many historians, merely as the incapable seaman who failed to win the Battle of Beachy Head, and thereby jeopardized the safety of the kingdom at a very critical time.