theaters of the campaigns of Marengo, Ulm,
and Jena, we find the same three zones, with this difference, that in
those campaigns the central direction was not the best. In 1800, the
direction of the left led straight to the left bank of the Po, on the
line of retreat of Melas; in 1805, the left zone was the one which led
by the way of Donauwerth to the extreme right, and the line of retreat
of Mack; in 1806, however, Napoleon could reach the Prussian line of
retreat by the right zone, filing off from Bamberg toward Gera.

In 1800, Napoleon had to choose between a line of operations on the
right, leading to the sea-shore toward Nice and Savona, that of the
center, leading by Mont-Cenis toward Turin, and that of the left,
leading to the line of communications of Melas, by way of Saint-Bernard
or the Simplon. The first two directions had nothing in their favor, and
the right might have been very dangerous,--as, in fact, it proved to
Massena, who was forced back to Genoa and there besieged. The decisive
direction was evidently that by the left.

I have said enough to explain my ideas on this point.

The subject of battles is somewhat more complicated; for in the
arrangements for these there are both strategical and tactical
considerations to be taken into account and harmonized. A position for
battle, being necessarily connected with the line of retreat and the
base of operations, must have a well-defined strategic direction; but
this direction must also depend somewhat upon the character of the
ground and the stations of the troops of both parties to the engagement:
these are tactical considerations. Although an army usually takes such a
position for a battle as will keep its line of retreat behind it,
sometimes it is obliged to assume a position parallel to this line. In
such a case it is evident that if you fall with overwhelming force upon
the wing nearest the line of retreat, the enemy may be cut off or
destroyed, or, at least, have no other chance of escape than in forcing
his way through your line.

I will here mention as illustrations the celebrated battle of Leuthen
in 1757, of which I have given an account in the history of Frederick's
wars, and the famous days of Krasnoi, in the retreat from Moscow in
1812.

[Illustration: Fig. 40.]

The annexed figure (40) explains the combination at Krasnoi. The line A
A is Napoleon's line of retreat toward C. He took the position B B to
cover his line. It is evident th