operations of war--of
command-in-chief--can be stored, is by far the most comprehensive and
thorough; for while utility cannot be denied to annual manoeuvres, and
to the practice of the sham battle, it must be remembered that these,
dealing with circumstances limited both in time and place, give a very
narrow range of observation; and, still more important, as was
remarked by the late General Sherman, the moral elements of danger and
uncertainty, which count for so much in real warfare, cannot be
adequately reproduced in mimic. The field of military history, on the
other hand, has no limit short of the military experience of the race;
it records the effect of moral influences of every kind, as well as of
the most diverse material conditions; the personal observation of even
the greatest of captains is in comparison but narrow. "What
experience of command," says one of the most eminent, "can a general
have, before he is called to command? and the experience of what one
commander, even after years of warfare, can cover all cases?"
Therefore he prescribes study; and as a help thereto tells the story
of one of his most successful campaigns, accompanying it with a
commentary in which he by no means spares himself. Napoleon abounds in
the same sense. "On the field of battle the happiest inspiration is
often but a recollection,"--not necessarily of one's own past; and he
admitted in after years that no finer work had been done by him than
in his first campaign, to which he came--a genius indeed, but--with
the acquisitions chiefly of a student, deep-steeped in reading and
reflection upon the history of warfare.

The utility of such study of military history to the intending warrior
is established, not only by a few such eminent authorities, but by a
consensus among the leading soldiers and seamen of our own day,
whether they personally have, or have not, had the opportunity of
command in war. It may be asserted to be a matter of contemporary
professional agreement, as much as any other current opinion that now
obtains. In such study, native individual capacity and individual
temperament will largely affect inference and opinion; not only
causing them to differ more or less, but resulting frequently in
direct opposition of conclusion. It cannot be otherwise; for, like all
other callings of active life, war is a matter, not merely of
knowledge and of general principles, but of sound judgment, without
which both information and