... barbette. The gorge face was covered by a demi-lune of good relief, arranged for one tier of guns in barbette, and was also provided with a ditch. The marshy formation, Cockspur island, on which Pulaski stood, was surrounded by broad channels of deep water, and the only near approach to it, on ground of tolerable firmness, was along a narrow strip of shifting sand on Tybee island. The people of ...