COUNTERFORTS. Masonry adjuncts, advantageous to all retaining walls, but especially to those which, like the escarps of fortresses, are liable to be battered. They are attached at regular intervals to the hinder face of the wall, and perpendicular to it; having various proportions, but generally the same height as the wall; they hold it from being thrust forward from behind, and, even when it is battered away, retain the earth at the back at such a steep slope that the formation of a practicable breach remains very difficult. When arches are turned between the counterforts, the strength of the whole structure is much increased: it is then called a _counter-arched revêtement_. COUNTERGUARD. In fortification, a smaller rampart raised in front of a larger one, principally with the intention of delaying for a period the besieger's attack. Other means, however, are generally preferred in modern times, except when a rapid fall in the ground renders it difficult to cover the main escarp by ordinary resources. COUNTER-LINE. A word often used for _contravallation_. COUNTERMARCH. To change the direction of a march to its exact opposite. In some military movements this involves the changing of front and wings. COUNTERMINES. Military defensive mines: they may be arranged on a system for the protection of the whole of a front of fortification by the discovering and blowing up not only the subterranean approaches of the besieger, but also his more important lodgments above. COUNTER-MOULD. The converse of _mould_ (which see). COUNTER-RAILS. The balustrade work, or ornamental moulding across a square stern, where the counter terminates. COUNTERSCARP. In fortification, the outer side of the ditch next the country; it is usually of less height, and less strongly revetted than the escarp, the side which forms the face of the rampart. COUNTER-SEA. The disturbed state of the sea after a gale, when, the wind having changed, the sea still runs in its old direction. COUNTERSIGN. A particular word or number which is exchanged between sentinels, and intrusted to those on duty. (_See_ PAROLE.) COUNTER-SUNK. Those holes which are made for the heads of bolts or nails to be sunk in, so as to be even with the general surface. COUNTER-TIMBERS. Short right-aft timbers for the purpose of strengthening the counter, and forming the stern. COUNTER-TRENCHES. _See_ COUNTER-APPROACHES. COUNTRY. A term synonymous with _station_. The place whither a ship happens to be ordered. COUP DE GRACE. The finishing shot which brings an enemy to surrender; or the wound which deprives an adversary of life or resistance. COUP DE MAIN. A sudden and vigorous attack. COUP D'ŒIL. The skill of distinguishing, at first sight, the weakness of an enemy's position, as Nelson did at the Nile. COUPLE, TO. To bend two hawsers together; coupling links of a cable; coupling shackles. COUREAU. A small yawl of the Garonne. Also, a narrow strait or channel.