s and commanding both banks. Mayence, Coblentz,
and Strasbourg, including Kehl, are true illustrations and models of
this kind. Places situated at the confluence of two great rivers command
three different fronts, and hence are of increased importance. Take, for
instance, Modlin. Mayence, when it had on the left bank of the Main the
fort of Gustavusburg, and Cassel on the right, was the most formidable
place in Europe, but it required a garrison of twenty-five thousand men:
so that works of this extent must be few in number.

4. Large forts, when encompassing populous and commercial cities, are
preferable to small ones,--particularly when the assistance of the
citizens can be relied on for their defense. Metz arrested the whole
power of Charles V, and Lille for a whole year delayed Eugene and
Marlborough. Strasbourg has many times proved the security of French
armies. During the last wars these places were passed without being
besieged by the invading forces, because all Europe was in arms against
France; but one hundred and fifty thousand Germans having in their front
one hundred thousand French could not penetrate to the Seine with
impunity, leaving behind them these well-fortified points.

5. Formerly the operations of war were directed against towns, camps,
and positions; recently they have been directed only against organized
armies, leaving out of consideration all natural or artificial
obstacles. The exclusive use of either of these systems is faulty: the
true course is a mean between these extremes. Doubtless, it will always
be of the first importance to destroy and disorganize all the armies of
the enemy in the field, and to attain this end it may be allowable to
pass the fortresses; but if the success be only partial it will be
unwise to push the invasion too far. Here, also, very much depends upon
the situation and respective strength of the armies and the spirit of
the nations.

If Austria were the sole antagonist of France, she could not follow in
the footsteps of the allies in 1814; neither is it probable that fifty
thousand French will very soon risk themselves beyond the Noric Alps, in
the very heart of Austria, as Napoleon did in 1797.[21] Such events only
occur under exceptional circumstances.

6. It may be concluded from what precedes,--1st, that, while fortified
places are essential supports, abuse in their application may, by
dividing an army, weaken it instead of adding to its efficiency; 2d,
t