This was the position of the French army at the famous battle of
Leipzig, which terminated the campaign of 1813 so fatally for Napoleon;
for the battle of Hanau was of no consequence, comparatively, in the
desperate situation of that army.
It strikes me that, in a situation like that of the French army
previous to the battle of Leipzig, a general should never calculate
upon any of those lucky chances which may arise out of a return to the
offensive, but that he should rather adopt every possible means to
secure his retreat. With this view, he should immediately cover himself
with good entrenchments, to enable him to repel with inferior numbers
the attack of the enemy, while his own equipments are crossing the
river. As fast as the troops reach the other side, they should occupy
positions to protect the passage of the rear guard, and this last
should be covered by a _tête de pont_ as soon as the army breaks up its
camp. During the wars of the Revolution, too little regard was paid
to entrenchments; and it is for this reason we have seen large armies
dispersed after a single reverse, and the fate of nations compromised
by the issue of one battle.