ccess depending
entirely upon a good system of marches.

On this subject, General Jomini, the great military historian of the
wars of the French Revolution, remarks that "we should depend entirely
upon neither organized masses, nor upon material obstacles, whether
natural or artificial. To follow exclusively either of these systems
would be equally absurd. The true science of war consists in choosing a
just medium between the two extremes. The wars of Napoleon demonstrated
the great truth, that distance can protect no country from invasion, but
that a state, to be secure, must have a good system of fortresses, and a
good system of military reserves and military institutions."

In all military operations _time_ is of vast importance. If a single
division of an army can be retarded for a few hours only, it not
unfrequently decides the fate of the campaign. Had the approach of
Blucher been delayed for a few hours, Napoleon must have been victorious
at the battle of Waterloo. An equilibrium can seldom be sustained for
more than six or seven hours between forces on the field of battle; but
in this instance, the state of the ground rendered the movements so
slow as to prolong the battle for about twelve hours; thus enabling the
allies to effect a concentration in time to save Wellington.

Many of Napoleon's brilliant victories resulted from merely bringing
troops to bear suddenly upon some decisive point. Rivoli in 1796-7,
Marengo in 1800, Ulm in 1805, Jena in 1806, Ratisbon in 1809, Brienne in
1814, and Ligny in 1815, are familiar examples. But this concentration
of forces, even with a regular army, cannot be calculated on by the
general with any degree of certainty, unless his communications are
perfectly secure. And this difficulty is very much increased where the
troops are new and undisciplined. When a country like ours is invaded,
large numbers of such troops must suddenly be called into the field. Not
knowing the designs of the invaders, much time will be lost in marches
and countermarches; and if there be no safe places of resort the
operations must be indecisive and insecure.

To a defensive army fortifications are valuable as points of repose,
upon which the troops, if beaten, may fall back, and shelter their sick
and wounded, collect their scattered forces, repair their materials, and
draw together a new supply of stores and provisions; and as rallying
points, where new troops may be assembled with safety, and t