Palisades
Palisades (from Lat. palus, stake), strong, 3–4 m long stakes with pointed tops, frequently used as an obstacle in the art of fortification, especially in conjunction with gates, where they were placed with minimal intervals, buried 1 m deep into the ground and firmly secured to each other. Defensive palisades, which allow infantry to fire from them (as opposed to the obstacle palisades), were often used to fortify open gorge lines, but are no longer applicable in the face of modern firearms. Palisades are easiest to remove by blasting. In the modern fortification, palisades have been replaced by iron palisade fences typically set in concrete foundations. In the Orient, one frequently encounters fortified towns where palisades form the outer slope of the parapet and earth is piled up behind them as the rampart (Palankas).
Source: Meyers Großes Konversations-Lexikon, 6. Auflage 1905–1909
Palisades, used as obstacles both in field fortifications and fortresses, and are therefore of different types, just as they are used in different ways. They are strong wooden stakes with pointed tops, and embedded in the ground, to make it difficult for an enemy to storm an earthwork or other fortification. They are planted close together; their length depends on the location where are to be used; they are usually 9 to 10 feet long and 4 to 6 inches thick. Free-standing palisades can only be used where they are not exposed to enemy artillery fire, and do not block our own fire; this would be the case on a high hill with gradual slopes for example, and in this case they would be pointed towards the enemy, set 2 to 3 feet into the ground, and 6 to 8 feet above ground; they will be held in place more securely by battens nailed against them 2 feet below the points and just above ground level. In conjunction with earthworks in open ground, they are planted vertically in case of a very narrow ditch, and obliquely in the case of a wider one, s0 that, they stand 7 feet tall in a 9 foot ditch; these palisades, too, are further secured by battens. The stronger they are, the more difficult they are to cut down; s. Fig. 33. Given enough time and timber, and if the bottom of the ditch is considerably wide, two rows of palisades may be planted in the ditch, in which case the front row is set vertically, and the rear row obliquely. Fig. 34.
In all other locations, palisades are not recommended for field fortifications, and even the ones mentioned here are easily demolished by a courages and determined enemy, because the palisades themselves provide cover for the most part of his work. To benefit from the amount of effort put into the palisade, it is therefore essential that the outer perimeter of the earthworks be designed such that the ditch, and the space beyond the palisade is enfiladed by flanking fire. In that case, the enemy will be shot dead as soon as they reach the palisade. Note that palisades are easier to cut down or pull down if they have gaps between them, and if they are planted less then 2 feet deep in the ground.
A special kind are those that are driven into the scarp, either horizontally or slanting down, and are named storm-poles (German Sturmpfähle, French fraises). Palisades are also used as a parapet, and occasionally as perimeter fencing at the entrances of earthworks, in which case they are usually given the name tambours. If they are to withstand enemy artillery, they must be one foot thick or even stronger. They are placed close to each other, 3 feet deep in the ground, and are usually secured, above and below, by strong cross members. Loopholes are cut six feet above ground, facing the enemy, and a banquette (fire-step) thrown up behind the palisade. If a ditch has been dug behind the banquette, loopholes are also cut immediately above the banquette, thereby creating a second firing line. Alternatively, two rows of palisades are emplaced, with 3 inch intervals, one row behind the other, but in such a way that the rear row, which is 2 feet shorter, closes the intervals of the front row; thereby creating embrasures. Palisades are used in a similar way for the fortification of buildings, for connecting individual parapet lines, anchoring flanks on steep terrain and slopes, creating caponiers across the ditch, etc. with good success.
When palisades are to be planted, a ditch is dug of the required depth, namely 2 feet in good soil, and 3 feet in bad. In this ditch, 2 palisades are placed 20 feet apart from each other, aligned, a line strung between them, and the remaining palisades placed along this line. If the palisades are set obliquely, in which case, by the way, the perpendicular height remains the same, a threshold is laid on the overhanging side, to which each palisade is attached, and which lies just above ground level; another is attached to the ends of the palisades below ground. The lower batten may be dispensed with in the case of vertical palisades, if one is attached at the top, provided that the soil is good; in bad soil, two battens are a must. One man can make about 3 to 5 palisades in an hour, and 24 to 40 in a day, once the timber has been obtained; if 10 men are detailed, 3 men cut wood, 2 saw and trim it, 2 split, and 3 sharpen the palisades and trim them. 3 men are able to place more than 56 palisades in a day.
In fortresses, they are mostly placed at the exits through the glacis, or on the banquette of the covered way, as in l’ Fig. 82 or qr Fig. 73, where they are placed along this line and closely together, so that only the muzzle of a shoulder arm may be put through; they are connected by strong battens at the top, and extend 3 feet above the crest of the glacis. If a second row of palisades is placed between each traverse of the covered way e’v oder xf’, Fig. 81, such as mn, Fig. 73, and behind it a second banquette, like m, Fig. 82, this is called a double-palisading. Palisades are also used in a dry ditch of the fortress, in different directions, as shown in Figs. 82 and 85; as well as in caponiers and other works; they could even be advantageous behind the cunettes.
Palisades in fortresses are usually made in three lengths; 8 feet for the covered way, in the dry ditches etc., where they are set 3 feet deep in the ground; 11 feet for the passages at the traverses; finally 6 feet, when they are used as storm-poles for the parapets, as in h Fig. 82 for example – A special type, suggested by Coehoorn, but which has not been employed yet, because of its inadequacy, consists of the mobile, or so-called rotating palisades.
Source: Rumpf, H. F.: Allgemeine Real-Encyclopädie der gesammten Kriegskunst (Berl. 1827)
Of Palisades
Palisades are stakes of a prismatic form (fig. 35 and fig. f). Their section, whose periphery is about 1½ feet, is usually an equilateral triangle. They are inserted 3 feet into the earth. Two workmen can make 80 a day; and three workmen will place 60 at least.
Palisades are either placed vertically, or very much inclined to the horizon, in which latter case they are usually called fraises; and an entrenchment is said, in the one case, to be palisaded, and in the other to be fraised.
To plant a palisade, a trench must be dug in the ground 3 feet deep, and 1½ feet wide, in which the palisades are to be set about 3 inches apart. Several of them are then fixed in the alignment by means of a cord, and the others successively brought to it after they have been well settled at the bottom by throwing in earth. Nothing then remains but to fasten them at top.
This is done by nailing or spiking them to a horizontal lath at the usual breast height, (4 feet 6 inches,) to which each palisade is fastened. This lath is at least 6 inches wide and 2 inches thick, a spike with two points is sometimes placed upon the lath, at each interval of the palisade, to prevent the enemy from setting his foot upon it to leap into the work, which may happen when they line a covered way. In this case, the horizontal piece is not more than 3 inches below the crest of the glacis.
“In order to place a fraise, its position, and the inclination to shelter it from the fire of cannon being determined, a course of small rests called the coussinet, is first placed horizontally in the body of the earth. Upon this the fraises are placed in a straight line; they are then fixed to the coussinet by nails or spikes. As soon as the work is completed, the earth is replaced above the coussinet. Fraises project usually 6 or 7 feet.” (Savart).
A row of palisades is placed either at the bottom of the ditch, in its middle, or at the foot of the counterscarp. Sometimes, but improperly, at the foot of the scarp. They are also planted in front of the counterscarp at the foot of the glacis; they are then defended by the direct fires of the entrenchment. Some engineers are opposed to this method of placing a palisade upon the covered way, because it prevents the troops from sallying out in order of battle. Without deciding this question, I believe that it is better not to use palisades, upon the curtains of the entrenchments of camps, and other works from which it is necessary to advance in order of battle: but there are also cases where the covered way must be palisaded.
There are several methods for placing fraises; upon the berm, perpendicular to the scarp or to the counterscarp, etc. Upon the berm or scarp they are more exposed to howitzers and other projectiles. When a fraise is placed on the berm, it is usually set horizontal at the natural level of the earth, or even dipping a little; it is thus charged with the whole weight of the parapet. Some engineers place it 4½ feet below the edge of the counterscarp. (fig. 35)
In all cases, attention must be paid, that they do nor rise above the level of the plunging fire of the parapet, and to hide them from cannon firing point blank, or from the view of the enemy.
Source: Lallemand, Henri Dominique: A Treatise on Artillery (New York 1820)