A gabion is an open cylinder made of brushwood, canvas, wire-netting, or iron bands used in fortification. Filled with loose earth, gabions are placed on end, in tiers, to form a wall behind which earth can be piled. They are usually constructed on location and made up of whatever materials are on hand.
John H. Finley ed. Nelson's Perpetual Loose-Leaf Encyclopaedia (vol. 5) (New York, NY: Thomas Nelson and Sons, 1917)