Marine Corps, Royal, a military force under the Lords Commissioners of the Admiralty, available for service either on sea or on land. The Marines were, in the 17th century, ordinary land soldiers detailed for service on board ship; but long before the close of that century they began to be specially raised, and they were then known as the Lord High Admiral's Maritime Regiment of Foot, or, briefly, as the Admiral's Regiment. In 1684 the corps included twelve companies. After 1684 several other maritime regiments, such as those of Colonel Colt, Sir Clondesley Shovel, and Lord Torrington, were raised and again disbanded; and it was not until the dawn of the 18th century that this most valuable force, the proud motto of which is "Per Mare, Per Terrain," began to assume the character which has ever since been associated with it. The corps is now divided into artillery (blue uniform) and light infantry (red uniform), and the headquarters of the former are at Portsmouth, while those of the three divisions of the latter are at Chatham, Plymouth, and Portsmouth respectively.