[mod. f. COUNTER- 3, 13 + MINE: cf. F. contremine, It. contramina (both 16th c.)]
1. Mil. A mine or subterranean excavation made by the defenders of a fortress, to intercept a mine made by the besiegers. Also, a permanent excavation made in fortification for the like purpose.
1548. Hall, Chron., 56 b. Least either they should make a countremyne or be an impediment to his worke men.
1579. Fenton, Guicciard., VI. (1599), 230. It is subiect to countermines on all sides.
1599. Shaks., Hen. V., III. ii. 67. The Duke, looke you, is digt himselfe foure yard vnder the Countermines.
1645. N. Stone, Enchir. Fortif., 47. Counter-Mynes are made in Ramparts or Bulwarkes, at the first new making of a Fort…. In them the least noise that is made in the outside is to be heard, and which way they work.
1686. Burnet, Trav., v. (1750), 276. All the Bastions have a Countermine that runneth along by the Brim of the Ditch.
1863. J. C. Morison, St. Bernard, IV. i. 412. He undermined the towers, and was met by the countermines of the garrison.
b. In naval war: A submarine ‘mine’ sunk in such a position as to explode the enemy’s mines by the concussion of its explosion.
The sea mines and countermines are cylinders, or other vessels, filled with an explosive; the mines being laid so as to defend a harbor, etc., by exploding under the ships of an assailant, the latter sinks his countermines in their supposed vicinity, and explodes them from a distance by electricity.
1880. Athenæum, 21 Aug., 242. [To] discover the approach of any hostile torpedo launches when they attempt to tow countermines against the line of defence…. The lines of countermines were laid and exploded in a masterly manner by the naval launches.
2. fig. A secret device or plot designed to frustrate another; a counter-plot.
1570. B. Googe, Pop. Kingd., III. 33 b. With dreames and fond deuice of men, and cursed countermine.
1611. Speed, Hist. Gt. Brit., IX. xx. (1632), 992. With secret countermines and open weapons of Law.
1647. May, Hist. Parl., III. vi. 100. Many Mynes and Countermynes were every day working with great industry on both sides.
1692. R. L’Estrange, Fables, 36 (O.). The Countermine was only an Act of Self-Preservation.
