[Illustration: FIG. 137.] 3. Commence and continue the digging as prescribed in the construction of the French gun-pit. The pockets _aa_ are for the reception of ammunition. 4. The ramp is laid out and completed after the pit is finished, or simultaneously with it, as may be most desirable. An ordinary gun detachment can construct this pit in one hour. THE AUSTRIAN GUN-PIT. A simple rectangular pit one and a half feet deep, with front epaulement and ramp. =Construction.=--Constructed similarly to the German, the earth from the pit being thrown to the front. It can be made in less than half an hour, and while affording no special cover to the cannoneers, as do the German and English, it can be made in half that time, and does not present a conspicuous target. [Illustration: FIG. 138.] It has the further advantage of very rapid cover, and of being capable of transformation into any desirable pit if there be time. THE ENGLISH GUN-PIT. This type is a true "gun-pit," the bottom being below the natural surface of the ground, sloping up at back of pit toward the rear. It affords excellent cover for the piece and its detachment, can be readily marked out, and constructed in a comparatively short time. The lateral trenches, if extended, would afford a covered way along the front of the battery. The defects in this pit are a contracted field of fire, the conspicuous mark which the embrasure gives the enemy, the lack of ammunition-pockets, and want of drainage. [Illustration: FIG. 139.] =Construction.=--1. Lay off 8 feet 6 inches on a line perpendicular to the probable direction of fire for the interior crest, and at the middle point of this line determine a perpendicular to it; on this perpendicular lay off from the interior crest distances of 6 feet, 10 feet, and 18 feet, and through their extremities determine lines parallel to the interior crest; on these lines find points that are 6 feet from the perpendicular on both sides of it, putting in a stake or sabre at each point so determined. Extend the parallels at 6 feet and 10 feet, 4 feet on each side, and mark the points thus established for the lateral trenches.