Gunpowder is assumed to be roughly tamped with sand-bags, guncotton untamped. If the guncotton is tamped, the charges may be reduced one half. Charges of guncotton must be equal in length to the breach which is to be made.
| Object Attacked. | Gunpowder. | Guncotton. | Remarks. | |||
| Brick arch. |  | 3/2BT2 |  | ¾BT2 | | The length of breach, B, should not be less than the height of the wall to be brought down. |
| Brick wall 2 ft. or less. | 2 lbs. per foot run | |||||
| Brick wall over 2 ft. | ½BT2 | |||||
| Brick piers. | ⅔BT2 | |||||
| Hard wood in any form, stockade, palisade, single timbers, trees, etc. | 40 to 100 lbs. for stockade | 3BT2 | In a concentrated charge, or for trees not over 12 in. in diameter in a necklace. | |||
| Do., do | ⅜T2 | In auger-hole; when the timber is not perfectly round, T smaller axis. | ||||
| Soft wood | Half the charges for hard wood | |||||
| Breastwork of horizontal balks, or earth between sleepers up to 3½ ft. thick. | 60 to 80 lbs. per 5 feet | 4 lbs. per foot | ||||
| Heavy rail stockade. | 7lbs. per ft. | |||||
| Fortress gate | 200 lbs. | 50 lbs. | ||||
| Iron plate | 3/2Bt2 | |||||
| Field- or siege-guns. | 1½ lbs. | On chase near muzzle. | ||||
| Heavier guns | 4 lbs. | In bottom of bore, tamped with water or sand. | ||||
| First-class iron rail | ⅔ lb. | Touching web of rail and near a chair. | ||||
| First-class steel rail | 4 oz. | Four rails placed around the charge will be cut simultaneously by it. | ||||
In the presence of an enemy increase above charges 50% to allow for contingencies.
House with Moderately Thick Walls.—Attack portions of walls between the windows, the charges being tamped, and inside the house if possible. Otherwise place outside, or one or two large charges inside untamped.
To demolish a building, a sufficient height of wall must be brought down to insure the arches over the doors and windows falling. The length of breach must be equal to this height. With very thick walls cut grooves.
To Cut Down Trees.—Place charge in an auger-hole bored horizontally into the tree at desired height. If tree be 1½ to 2 feet in diameter, use two holes. With a little care they can be bored so as to meet in the centre, in which case one detonator will suffice to fire the charge; with plenty of detonators it may be better to fire one hole first and then a second hole in the uninjured part of the tree, and so on.
The tree may be made to fall in any required direction by attaching a rope to the upper branches, and taking the strain on it before firing.
The guncotton may be hung around the tree, but this often fails with trees over 12 inches in diameter.
A hole may be dug under the roots. Dig down by the side of the tree and then horizontally under the bottom close to the wood, the hole being just large enough for the cartridge.