several army corps, or even of several divisions, operating under the
orders of one commander-in-chief. The army in this sense (distinguished
by a number or by a special title) varies, therefore, with
circumstances. In the American Civil War, the Army of the Ohio consisted
in 1864 only of the army staff and the XXIII. corps. At the other
extreme we find that the German II. Army in 1870 consisted of seven army
corps and two cavalry divisions, and the III. Army of six army corps and
two cavalry divisions. The term "army" in this sense is therefore very
elastic in its application, but it is generally held that large groups
of corps operating in one theatre of war should be subdivided into
armies, and that the strength of an army should not exceed about 150,000
men, if indeed this figure is reached at all. This again depends upon
circumstances. It might be advisable to divide a force of five corps
into two armies, or on the other hand it might be impossible to find
suitable leaders for more than two armies when half a million men were
present for duty. In France, organization has been carried a step
further. The bulk of the national forces is, in case of war, organized
into a "group of armies" under a commander, usually, though incorrectly,
called the _generalissimo_. This office, of course, does not exist in
peace, but the insignia, the distinctive marks of the headquarters flag,
&c., are stated in official publications, and the names of the
generalissimo and of his chief of staff are known. Under the
generalissimo would be four or five army commanders, each with three or
four army corps under him. Independent of this "group of armies" there
would be other and minor "armies" where required.