IF a supreme decision should lie in their defence and their attack, they place the assailant in an advantageous situation, for their wide extent is still more in opposition to all the requirements of a decisive battle than the direct defence of a river or a mountain range. Eugene's lines of Denain, 1712, are an illustration to the point here, for their loss was quite equal to a complete defeat, but Villars would hardly have gained such a victory against Eugene in a concentrated position. If the offensive side does not possess the means required for a decisive battle, then even lines are treated with respect, that is, if they are occupied by the main body of an army; for instance, those of Stollhofen, held by Louis of Baden in the year 1703, were respected even by Villars. But if they are only held by a secondary force, then it is merely a question of the strength of the corps which we can spare for their attack. The resistance in such cases is seldom great, but at the same time the result of the victory is seldom worth much.
The circumvallation lines of a besieger have a peculiar character, of which we shall speak in the chapter on the attack of a theatre of war.
All positions of the cordon kind, as, for instance, entrenched lines of outposts, etc., etc., have always this property, that they can be easily broken through; but when they are not forced with a view of going further and bringing on a decision, there is so little to be gained in general by the attack, that it hardly repays the trouble expended.