Single Sap Small 320×81 Medium 640×163 Large 1024×260 Download Tiff Original 2400×610 | (220.7 KB) Description In military affairs, a narrow ditch or trench by which approach is made to a fortress or designed place when within range of fire. This is a section of single sap, showing portion of gabions. Keywords ditch, fort, fortress, fortresses, Military, Sap, single Galleries Military Fortification Source: Logan Marshall, Ed. International Self-Pronouncing Reference Library (five vols.) (Philadelphia, PA: International Press, 1911)
