_The Rear-trench Party._--This party excavates to a width of 7' 6" the rear trench and the communications with the parallel or approach. Each digger has a task 4' wide, 7' 6" long, and 3' 6" deep. The two directly in rear of each gun portion throw the earth to the rear, the others throw it to the front, leaving a berm of 4' 6" at the rear of the traverse. The men of the _reserve_ who are not otherwise occupied fill sand-bags from the earth thrown to the rear, and cut a ramp 8 feet wide and not steeper than 1/4, in rear of each gun-portion, when needed. It is essential that the excavation of the gun-portion be finished by the first relief, so that the platforms may be laid by the second relief in time to allow the guns to be placed before daylight. The first relief leaves in the battery the tools required by the second and carries the rest back to the depot. _The second relief_ is divided into three parties and a strong reserve of one quarter or one fifth of its strength. The first, or _front-ditch party_, works in the front ditch, widening it 6 feet and throwing the earth back to form the front of the parapet. The shovellers, one to each two diggers, spread and level it. The task of a digger is 5' wide, 6' long, and 3' 6" deep. The second, or _platform party_, places the platforms and gives way to the gun detachments. The third, or _rear-trench party_, widens the trench 3' towards the front by cutting off the rear of the traverses. The _reserve_ completes any work left unfinished by the first relief, fills sand-bags and places them around the gun portions, digs ditches and drainage-pits when needed, and does any other work necessary for the completion and arming of the battery. When a tramway is laid in the trench for bringing up the guns and carriages, the ramps in rear need not be cut. =51.= =Alternative Construction in Position Very Much Exposed.=--When the earth thrown up in making the splinter-proofs cannot be concealed, it may attract such a severe fire from the defence as to make the above-described construction impossible. In this case the battery is traced as above described, the balks for covering the splinter-proofs are placed in position resting on bearing-planks, and the construction of the front ditch, gun portions, and rear trench are commenced at once; and the battery is as nearly finished as time allows, and armed if possible. The splinter-proofs are subsequently mined out and the remaining necessary details finished before opening fire.