4. For this reason, we must never post one of our own batteries so that the enemy's guns will take it _obliquely_, or _in flank_; unless, indeed, by doing so, we may probably obtain some important and decisive effect before it can be destroyed, or made unserviceable. 5. Batteries should be so placed as to _command the whole ground in our front_, even almost up to our bayonets, and so as to be able to direct their fire towards every point; at all events, so that a fire can be kept up on the enemy till he is within short musket-range. It is manifest that the best position for a battery, to enable it to effectually cover the entire ground in our front, would not be in our line of battle, but in advance of one of its flanks, from which it could take the enemy's troops advancing over it, in enfilade. 6. Artillery fire from _an unexpected quarter_ always has a powerful moral effect. Two guns, even, hoisted up to a place where the enemy does not dream of there being any, may have a decisive effect. IV.--Posting of Batteries and of Pieces as between themselves. 1. The best mode of posting batteries is in the form of a crescent, its horns pointing towards the enemy, or forming the sides of a re-entering angle; for this gives a _convergent fire_ to the enemy's divergent one. Its inconvenience is, the exposure of its flanks to attack, or to enfilade. Therefore, when such a position is adopted, its flanks must be protected by natural obstacles or by artificial defences. 2. Batteries, or parts of batteries, should be at _supporting distances_ from each other; that is, not over six hundred yards apart, so as to effectually cover the whole ground between them, in case of need, with grape and canister. When rifled guns are used, this distance may be increased. 3. _A long line of guns_ in our line of battle is objectionable; for, if it should become necessary to withdraw them, they would leave a dangerous interval. 4. It is dangerous to collect _a great many pieces in one battery_, especially in the beginning of an action, when the enemy is fresh, for it strongly tempts him to capture it. When used, such a battery should have powerful supports to protect it, or should be sheltered by a village, a defile, or other cover, occupied beforehand. 5. Although, to be used offensively, guns should be in strong masses, in order to strike a decisive blow on some single point; this is by no means the case when _used defensively_; for, (1.) It is only when guns are more or less scattered over different parts of the field, that they can be made to give a cross-fire on the enemy's advancing columns, or on any part of his line. (2.) If the position where they are massed does not happen to be attacked, they become useless, while stripping the rest of the line. (3.) If they are captured, all the artillery is lost at once, as happened to the Austrians at the battle of Leuthen, causing their defeat.