the 9th. Maunoury's counter-attack on the left had compelled the
Germans to weaken their centre. Not only was Von Buelow's right
exposed, but a gap had been left between his left and Von Hausen's
right, possibly for troops which were detained at Maubeuge or had been
diverted to East Prussia. Nor was this all, for his centre was bogged
in the famous marshes of St. Gond. Foch struck hard at Von Buelow's
centre, right, and left, and by the morning of the 10th he had smashed
the keystone of the German arch. Meanwhile, on the 9th Maunoury had
cleared the Germans from the Ourcq, the British had crossed the Marne
at Chângis, and reached it at Château-Thierry, and D'Esperey farther
east. Von Kluck now received considerable reinforcements which Von
Buelow needed more, and the latter's rapid retreat made even
reinforcements useless for holding the Ourcq. It was equally fatal to
success against Langle and Sarrail, and on the 10th the German retreat
became general. By the end of the week the Germans were back on a line
running nearly due east from a point on the Oise behind Compiègne to
the Aisne, along it to Berry-au-Bac, and thence across Champagne and
the Argonne to Verdun. They had failed in Lorraine as well, where the
climax of their attack was from the 6th to the 9th. Castelnau then
took the offensive, and by the 12th had driven the Bavarians from
before Nancy beyond the Meurthe, and out of Lunéville and St. Dié.

The German right had fallen back thirty-five miles and the centre
nearly fifty; but the retreat was not a rout, and the losses in guns
and prisoners were meagre. The first battle of the Marne was important
by reason of what it prevented the Germans from doing, rather than by
reason of what the Allies achieved, and they had to wait nearly four
years for that precipitate evacuation of France which it was hoped
would follow upon the German repulse from the Marne in September 1914.
Nevertheless it was one of the decisive battles and turning-points of