A mortar battery will not require any long fascines for the lining of the embrazures. The simplest method of ascertaining the number of fascines for a mortar battery, or for any other plain breast work, is to divide the length of work to be fascined in feet, by the length of each fascine in feet, for the number required for one layer, which being multiplied by the number of layers required, will of course give the number of fascines for facing the whole surface. If a battery be so exposed as to require a shoulder to cover it in flank, about 50 fascines of 9 feet each will be required for each shoulder. Each fascine of 18 feet will require 7 pickets. ” ” ” 9 feet ” ” 4 ” 12 workmen of the line, and 8 of the artillery, are generally allotted to each gun. If to the above proportion of materials, &c. for a battery of two guns, there be added for each additional gun, 30 fascines of 9 feet, and 10 of 18 feet, with 12 workmen, the quantity may easily be found for a battery of any number of pieces. The workmen are generally thus disposed; one half the men of the line in the ditch at 3 feet asunder, who throw the earth upon the berm; one fourth upon the berm at 6 feet asunder, to throw the earth upon the epaulment, and the other quarter on the epaulment, to level the earth, and beat it down. The artillery men carry on the fascine work, and level the interior for the platforms. This number of workmen may complete a battery in 36 hours, allowing 216 cubic feet tn be dug and thrown up, by each man _in the ditch_ in 24 hours. _Tools for the Construction of a Battery._ _Intrenching_—1½ times the number of workmen required; half to be pick axes, and half shovels or spades, according to the soil. _Mallets_—3 per gun. _Earth Rammers_—3 per gun. _Crosscut Saws_—1 to every two guns. _Handbills or Hatchets_—2 per gun. This estimate of tools and workmen, does not include what may be required for making up the fascines, or preparing the other materials, but supposes them ready prepared. For these articles, see the words _Fascine_, _Gabion_, _Platform_, &c. and for the construction of field magazines for batteries, see the word _Magazine_. NOTE. The following estimate of the quantity of earth which may be removed by a certain number of workmen in a given time, may serve to give some idea of the time required to raise any kind of works. 500 common wheel barrows will contain 2 cubic toises of earth, and may be wheeled by one man, in summer, to the distance of 20 yards up a ramp, and 30 on a horizontal plain, in one day. In doing which he will pass over, going and returning, about 4 leagues in the first case, and 6 in the last. Most men, however, will not wheel more than 1¾ toise per day. Four men will remove the same quantity to four times the distance.