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"Crown-work, in Fortification, is formed to strengthen a weak front, or to occupy ground which might facilitate the enemy's operations. It consists of two faces inclined to each other at an angle, with a bastion in the middle, and half-bastions at the two ends; and it is connected with the main body of the work by two long sides. RMNPS is the crown-work, in front of and protecting the ravelin O. Both of these works are entirely beyong the main ditch of the place, but each has also a ditch of its own." — Chambers' Encyclopedia, 1875

Crown-Work

"Crown-work, in Fortification, is formed to strengthen a weak front, or to occupy ground which might…