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"A projecting watchtower, or other advanced work, before the gate of a castle or fortified town. The term Barbican was more specially applied to the outwork intended to defend the drawbridge, which in moden fortifications is called the tete du pont." — Chambers' Encyclopedia, 1875

Barbican

"A projecting watchtower, or other advanced work, before the gate of a castle or fortified town. The…

"Crannoge, the name given in Ireland and in Scotland to the fortified islands in lakes which were in common use as dwelling-places and places of refuge among the Celtic inhavitants. The etymology of the word is uncertain, but it is believed to refer to the timber which was employed either in the fortification of the island, or in the construction of the houses which were placed upon it." — Chambers' Encyclopedia, 1875

Crannoge

"Crannoge, the name given in Ireland and in Scotland to the fortified islands in lakes which were in…

"Fortifying the Camp." — Greenough, 1899

Fortifying Camp

"Fortifying the Camp." — Greenough, 1899

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.

Gabion

A gabion is an open cylinder made of brushwood, canvas, wire-netting, or iron bands used in fortification.…