![]() ![]() 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. By the addition of further courses the fabric is raised to the required height. 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. When this first course has been placed in position and fastened together, another course is laid on top. 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. 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. “Gallic walls are always built more or less on the following plan. Others were fixed also a little above the bridge, so that if the natives tried to demolish it by floating down tree-trunks or beams, these buffers would break the force of the impact and preserve the bridge from injury.” In spite of the strength of the structure, additional piles were fixed obliquely to each pair of the original piles along the whole length of the downstream side of the bridge, holding them up like a buttress and opposing the force of the current. A series of these piles and transverse beams was carried right across the stream and connected by lengths of timber running in the direction of the bridge on these were laid poles and bundles of sticks. The pairs of piles being thus held apart, and each pair individually strengthened by a diagonal tie between the two piles, the whole structure was so rigid, that, in accordance with the laws of physics, the greater the force of the current, the more tightly were the piles held in position. The upper pair was kept at the right distance from the lower pair by means of iron braces, one of which was used to fasten each pile to the end of the beam. The two pairs were then joined by a beam two feet wide, whose ends fitted exactly into the spaces between the two piles forming each pair. Opposite these, forty feet lower down the river, another pair of piles was planted, similarly fixed together, and inclined in the opposite direction to the current. These he lowered into the river with appropriate tackle, placed them in position at right angles to the bank, and drove them home with pile-drivers, not vertically, as piles are generally fixed, but obliquely, inclined in the direction of the current. He took a pair of piles a foot and a half thick, slightly pointed at the lower ends and of a length adapted to the varying depth of the river, and fastened them together two feet apart. “The method he adopted in building the bridge was as follows. Moreover, when it began to blow hard and they were running before the wind, they weathered the storm more easily they could bring in to shallow water with greater safety, and when left aground by the tide had nothing to fear from reefs or pointed rocks – whereas to our ships all these risks were formidable.” We could not injure them by ramming because they were so solidly built, and their height made it difficult to reach them with missiles or board them with grappling-irons. ![]() In meeting them the only advantage our ships possessed was that they were faster and could be propelled by oars in other respects the enemy’s were much better adapted for sailing such treacherous and stormy waters. They used sails made of raw hides or thin leather, either because they had no flax and were ignorant of its use, or more probably because they thought that ordinary sails would not stand the violent storms and squalls of the Atlantic and were not suitable for such heavy vessels. The anchors were secured with iron chains instead of ropes. The cross-timbers, which consisted of beams a foot wide, were fastened with iron bolts as thick as a man’s thumb. ![]() Exceptionally high bows and sterns fitted them for use in heavy seas and violent gales, and the hulls were made entirely of oak, to enable them to stand any amount of shocks and rough usage. They were made with much flatter bottoms, to help them to ride shallow water caused by shoals or ebb-tides. “The Gauls’ own ships were built and rigged in a different manner from ours. ![]()
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