hese apparently unguarded openings a strong body of uhlan
patrols advanced, riding southward until they reached Nogent, south of
Paris, and seemingly with the whole rich country of central France laid
wide open to a sharp and sudden attack. Among the many strange features
of this series of the battles of the Marne this must certainly be
reckoned as one. Though possessing an unequaled military organization,
though priding itself on its cavalry scouts, though aided by aerial
scouts, and though well supplied with spies, yet the Allied armies, with
the age-old device of a forest, were able to cloak their movements from
this perfectly organized and powerful invading army. Much of the credit
of this may be assigned to the French and English aircraft, which kept
German scouting aircraft at a distance. But the Allied generals were
astounded at the result of their maneuver, which, as they admitted
afterward, was merely a military precautionary measure against the
discovery of artillery sites, and a device to keep the enemy in general
ignorance.

On Saturday, September 5, 1914, at the extreme north of the line of the
two armies facing each other across the Ourcq, an artillery duel began.
The offensive was taken by the French, and though in itself it was not
more striking than any of the artillery clashes that had marked the
previous month's fighting, it was significant, for it marked the
beginning of the battles of the Marne. The plans of General Joffre were
complete, but the actual point at which the furious contest should begin
was not yet determined. In the northern Ourcq section, however, the
realization by the French that they were actually on the offensive at
last, that the long period of retreat was over, could not be
restrained. The troops were eager to get to work with the bayonet, and
greatly aided by their field artillery, in which mobility had been
sacrificed to power, they quickly cleared the hills to the westward of
the Ourcq. By nightfall of September 5, 1914, the country west of the
Ourcq was in French hands. But to cross that river seemed impossible.
General von Kluck's heavy artillery had been left behind to hold that
position, and every possible crossing was covered with its own blast of
death.

Here General von Kluck's generalship was successful. It might have been
regarded as risky to leave 100,000 men to guard a river confronted by
250,000 picked and reenforced French troops. But General von Kluck's
faith