to retreat; but it may certainly cause him to do so by threatening his line of retreat, and, therefore, it may have the same effect as the action against the line of communication, by working as a demonstration. But as already said, none of these effects are to be expected from the mere turning which has been effected, from the mere geometrical form given to the disposition of the troops, they only result from the conditions suitable to the same.
In order to learn more distinctly these conditions, we shall separate completely the two actions against the flank, and first consider that which is directed against the communications.
Here we must first establish two principal conditions, one or other of which must always be forthcoming.
The first is, that the forces used for this action against the flank of the enemy must be so insignificant in numbers that their absence is not observed in front.
The second, that the enemy’s