cted several of these
changes; for in his bold invasions he was provided with new plans to
meet unforeseen events.

At the battle of Austerlitz, if defeated, he had resolved to adopt a
line of operations through Bohemia on Passau or Ratisbon, which would
have opened a new and rich country to him, instead of returning by
Vienna, which route lay through an exhausted country and from which the
Archduke Charles was endeavoring to cut him off. Frederick executed one
of these changes of the line of operations after the raising of the
siege of Olmutz.

In 1814 Napoleon commenced the execution of a bolder maneuver, but one
which was favored by the localities. It was to base himself upon the
fortresses of Alsace and Lorraine, leaving the route to Paris open to
the allies. If Mortier and Marmont could have joined him, and had he
possessed fifty thousand more men, this plan would have produced the
most decisive results and have put the seal on his military career.

13. As before stated, the outline of the frontiers, and the geographical
character of the theater of operations, exercise a great influence on
the direction to be given to these lines, as well as upon the advantages
to be obtained. Central positions, salient toward the enemy, like
Bohemia and Switzerland, are the most advantageous, because they
naturally lead to the adoption of interior lines and facilitate the
project of taking the enemy in reverse. The sides of this salient angle
become so important that every means should be taken to render them
impregnable. In default of such central positions, their advantages may
be gained by the relative directions of maneuver-lines, as the following
figure will explain. C D maneuvering upon the right of the front of the
army A B, and H I upon the left flank of G F, will form two interior
lines I K and C K upon an extremity of the exterior lines A B, F G,
which they may overwhelm separately by combining upon them. Such was the
result of the operations of 1796, 1800, and 1809.

[Illustration:
Fig. 4.

K
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F LLLLLLLLLLLLL G / \ A LLLLLLLLLLLLLL B
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