tory; but very grave errors will result, if we attempt to
apply in the armies of the present day the tactics of the ancients. This
fault has been committed by more than one man of merit, for want of
reflection upon the great difference between our missile weapons and
those of the ancients, and upon the resulting differences in the
arrangement of troops for combat." Our own military leaders have not
entirely avoided mistakes of this kind in the conduct of the present
war.

The treatise before us elucidates the general principles of strategy and
tactics, and applies them to the different classes of field--operations,
without entering into details, or describing the minor manoeuvres,
which belong more appropriately to another class of works.

The first chapter treats of bases and lines of operations, strategic
points, plans of offensive and defensive campaigns, and strategical
operations. Under the last head are embraced forward movements and
retreats, diversions, (combined movements and detachments,) the pursuit
of a defeated enemy, and the holding of a conquered country. The great
lesson of the chapter, prominent in almost every paragraph, is the
necessity of _concentration_. Divergent marches, scattering of forces,
unless ample facilities are secured for a speedy rally, when necessary,
to a common point, are among the most fruitful sources of disaster.

The organization of armies next receives attention. The explanation of
the composition of the army, its divisions and subdivisions, and the
adjustment of the relative proportions of the different classes of
troops, is brief and lucid. In the article on the formation of troops
the relative merits of formation in two ranks or three are discussed at
length.

Under the head of marches and manoeuvres are considered the rules by
which these movements should be conducted. These apply to the adjustment
of the columns, and the division, when necessary, of the forces upon
different roads in order to facilitate progress and make subsistence
more easy, the detailing of scouts and advance and rear guards, etc. The
adaptation of these rules to forward movements and battles leads to a
description of the order of march of the division, the precautions to be
observed in the passage of defiles, bridges, woods, and rivers, and when
the column has arrived in the presence of the enemy, and the conduct of
flank marches, marches in retreat, and the simultaneous movement of
several columns.