possess a quick eye, because
his especial duty is to note the disposition of the troops immediately
facing him, the placing of the artillery, and any local movements of the
forces that may be in progress. Consequently the aviator engaged on
this service may be absent from his lines for only a few minutes,
comparatively speaking; the intelligence he acquires must be speedily
communicated to the force to which he is attached, because it may
influence a local movement.

The strategical reconnaissance, on the other hand, affects the whole
plan of campaign. The aviators told off for this duty are attached to
the staff of the Commander-in-Chief, and the work has to be carried out
upon a far more comprehensive and elaborate scale, while the airmen
are called upon to penetrate well into the hostile territory to a point
thirty, forty, or more miles beyond the outposts.

The procedure is to instruct the flier either to carry out his
observations of the territory generally, or to report at length upon a
specified stretch of country. In the latter event he may fly to and
fro over the area in question until he has acquired all the data it is
possible to collect. His work not only comprises the general disposition
of troops, defences, placing of artillery, points where reserves are
being held, high-roads, railways, base camps, and so forth, but he is
also instructed to bring back as correct an idea as possible of what
the enemy proposes to do, so that his Commander-in-Chief may adjust
his moves accordingly. In order to perform this task with the requisite
degree of thoroughness it is often necessary for the airman to remain in
the air for several hours continuously, not returning, in fact, until he
has completed the allotted duty.

The airman engaged in strategical aerial reconnaissance must possess,
above all things, what is known as a "military" eye concerning the
country he traverses. He must form tolerably correct estimates of the
forces beneath and their character. He must possess the ability to
read a map rapidly as he moves through the air and to note upon it all
information which is likely to be of service to the General Staff.
The ability to prepare military sketches rapidly and intelligibly is
a valuable attribute, and skill in aerial photography is a decidedly
useful acquisition.

Such men must be of considerable stamina, inasmuch as great demands
are made upon their powers of endurance. Being aloft for several hours