Gallic walls are always built more or less on the following plan. Balks of timber are laid on the ground at regular intervals of two feet along the w… - Gaius Julius Caesar

" "

Gallic walls are always built more or less on the following plan. Balks of timber are laid on the ground at regular intervals of two feet along the whole line on which the wall is to be built, at right angles to it. These are made fast to one another by long beams running across them at their centre points, and are covered with a quantity of rubble; and the two-foot intervals between them are faced with large stones fitted tightly in. When this first course has been placed in position and fastened together, another course is laid on top. The same interval of two feet is kept between the balks of the second course, but they are not in contact with those of the first course, being separated from them by a course of stones two feet high; thus every balk is separated from each of its neighbours by one large stone, and so held firmly in position. By the addition of further courses the fabric is raised to the required height. This style of building presents a diversified appearance that is not unsightly, with its alternation of balks and stones each preserving their own straight lines. It is also very serviceable and well adapted for defending a town: the masonry protects it from fire, the timber from destruction by the battering-ram, which cannot either pierce or knock to pieces a structure braced internally by beams running generally to a length of forty feet in one piece.