To find the length of Fuzes for any Range.
The 13 and 10 inch fuzes of the same length burn so nearly equal, that one common length answers both, as do the 8 inch, 5¹⁄₂ and 4²⁄₅. Therefore, to find the length of fuze for any range, multiply the time of flight by 22 for the 13 and 10 inch, and by 24 for the 8, 5¹⁄₂ and 4²⁄₅; which is the decimal part of an inch a fuze burns in a second. Fuzes are thought to keep better by being painted; and for field service, are often marked off by black lines into seconds and ¹⁄₂ seconds.
G.
GABION, in fortification, is a kind of basket, made of ozier-twigs, of a cylindrical form, having different dimensions, according to what purpose it is used for. Some gabions are 5 or 6 feet high, and 3 feet in diameter: these serve in sieges, to carry on the approaches under cover, when they come pretty near the fortification. Those used in field-works are 3 or 4 feet high, and 2¹⁄₂ or 3 feet diameter. There are also gabions, about 1 foot high, 12 inches diameter at top, and from 8 to 10 at bottom, which are placed along the top of the parapet, to cover the troops in firing over it, they are filled with earth.
In order to make them, some pickets, 3 or 4 feet long, are struck into the ground, in form of a circle, and of a proper diameter, wattled together with small branches, in the manner of wattled fences. Batteries are often made of gabions. See [Battery].
Gabions.—Small gabions of 3 feet high, and 2 feet diameter, are made with least trouble, and are easiest carried. The pickets for them must be 1¹⁄₂ or 2 inches thick, and 4 feet long. Large gabions are 6 feet high, and 3 feet in diameter; and require two men to carry them. The smallest gabions or baskets are formed of pickets, 1 inch in thickness, and 1 foot long: they are 12 inches in diameter at top, and 10 at bottom. The small gabions have 7 or 8 pickets, the large ones 9 or 10.
To make them—The pickets are first to be fixed in the ground in a circle, the size or the bottom of the intended gabion; then a few twigs are to be wove through the upper ends, to keep them from flying out; afterwards the work must be begun at the bottom and continued upwards; and the whole being well driven down with a mallet, the edges must be secured by twigs, wattled up and down. The twigs of willow, birch, hazle, alder, poplar, and beech are proper for this purpose. The top of the gabion must be made very even, because that becomes the bottom when finished. Four men are usually employed on each gabion, with a billhook, a mallet, a spade, and two axes. Two collect the wood, while the other two form the gabion. A 3 foot gabion ought to be made in half an hour.
Stuft-Gabions, in fortification, are made in the same manner as the former: they are only filled with all sorts of branches and small wood, and are 4 or 6 feet long: they serve to roll before the workmen in the trenches to cover them in front against musquet-shot.
Gabion farci, Fr. a stuft gabion.
GABIONADE, Fr. a term made use of when a retrenchment is suddenly thrown up and formed of gabions, for the purpose of covering the retreat of troops, who may be obliged to abandon a work, after having defended it to the last extremity. Every parapet that is made of gabions is generally called gabionade.