army have been properly denominated its _impedimenta_, and
their movement and protection is one of the most difficult incidental
operations of warfare--particularly in a country like Virginia, where
the art of road making has attained no high degree of perfection, and
where the forests swarm with guerillas.

To an unaccustomed observer the concourse of the trains of an army, in
connection with any rapid movement, would give the idea of inextricable
confusion. It is of course necessary to move them upon as many different
roads as possible, but it will frequently happen that they must be
concentrated in a small space, and move in a small number of columns.
During the celebrated 'change of base' from Richmond to Harrison's
Landing, the trains were at first obliged to move upon only one
road--across White Oak Swamp--which happened fortunately to be wide
enough for three wagons to go abreast. There were perhaps twenty-five
hundred vehicles, which would make a continuous line of some forty or
fifty miles. While the slow and toilsome course of this cumbrous column
was proceeding, the troops were obliged to remain in the rear and fight
the battles of Savage Station and White Oak Swamp for its protection. A
similar situation of trains occurred last fall when General Meade
retired from the Rappahannock, but fortunately the country presented
several practicable routes. It is on a retreat, particularly, that the
difficulty of moving trains is experienced, and thousands of lives and
much valuable material have been lost by the neglect of commanding
officers to place them sufficiently far in the rear during a battle, so
as to permit the troops to fall back when necessary, without
interruption.

A march being ordered, supplies according to the capacity of the trains,
are directed to be carried. The present capacity of the trams of the
Army of the Potomac is ten days' subsistence and forage, and sixty
rounds of small-arm ammunition--the men carrying in addition a number of
days' rations, and a number of rounds, upon their persons. When the
wagons reach camp each evening, such supplies as have been expended are
replenished from them. As a general rule the baggage wagons camp every
night with the troops, but the exigencies are sometimes such that
officers are compelled to deny themselves for one or even two weeks the
luxury of a change of clothing--the wagons not reaching camp, perhaps,
till after midnight, and the troops resuming thei