e he is covering. But his action in _protecting_ the Main Body is
unfettered by any considerations of prudence, and must ever be vigorous
and resolute, any risks being taken that ensure the safety of the Main
Body. On the morning of the _Battle of Nachod_ (June 27, 1866) the
Advanced Guard of General Steinmetz's V. Corps (of the Army of the
Crown Prince of Prussia) was in bivouacs on a plateau, after emerging
from a long and narrow defile through which the Main Body must march to
the open country beyond. About 8 a.m. the cavalry of the Vanguard was
checked by the advanced troops of the VI. Austrian Corps. It was
imperative that the Prussian Advanced Guard should hold the plateau
until the Main Body had extricated itself from the defile. By the
rapid and accurate fire of the infantry and horse artillery, and the
co-operation of the cavalry against the Austrian squadrons, the thin
line was maintained for more than three hours. Less than 7 battalions
of infantry, with 13 squadrons of cavalry and 3 batteries of light
artillery, kept in check 21 battalions, 11 squadrons, and 4 batteries.
Had the Advanced Guard suffered itself to be driven back on the Main
Body in the defile a disaster could scarcely have been avoided, and
owing to the steadfast endurance of the Advanced Guard the Main Body
was able to drive the Austrian Corps from the field.

ADVANCED GUARD PROBLEMS.--The Advanced Guard commander must be able to
appreciate without delay {111} the situation which confronts his force,
and to solve the problem before him with regard solely to the interests
of the force he is covering.

(a) If the Vanguard is held up by the enemy who is ascertained to be
inferior in strength to the Advanced Guard, the commander will transmit
information to the Main Body and will attack vigorously to disperse the
enemy, in order that the movements of the Main Body may not be delayed.
A fire attack would be organised on the front of the enemy, supported
by close-range artillery fire, and a turning movement with Lewis guns
and rifles on one or both flanks. If the enemy held to a covered
position they could be ejected by rifle bombers or light mortars from a
flank, while artillery and machine guns prevented aimed fire at the
attacking force.

(b) If fire is opened on the Vanguard and definite information as to
the strength and dispositions of the enemy cannot be ascertained, such
information as had been gained would be transmitted and a bol