Sarrail was called upon to deal 'with a new peril. Early in the afternoon of the 8th a message was received saying: " Fort Troyon violently bombarded this morning by heavy guns of large calibre." The despatch closed with the ominous state- ment that the state of affairs was critical, and that 48 hours was all the commandant expected to be able to hold out. The situa- tion of Gen. Sarrail was now exceedingly serious. Very violent attacks were in progress against his right and centre; his left was in danger of being rolled up; and now this new peril threatened his rear. Fort Troyon was a small work dating from 1879, of practically obsolete design, the armament of which consisted of four medium guns, twelve smaller, and a couple of mortars, while the garrison numbered some 350 of all ranks. The bom- bardment was to last for four days from the 8th to the izth and was then succeeded by a thrust which created the well- known St. Mihiel salient, destined to remain as a dent in the French line until it was flattened out by the Americans four years later. Here it is only necessary to say that the garrison of Fort Troyon put up a stout resistance, and that the fortifications, obsolete though they were, proved sufficient to keep the cas- ualties of the defenders surprisingly low. On the loth the place was relieved by the arrival of a French cavalry division from Toul; and although upon the following day the Germans re- newed their attacks upon it these had lost most of their signif- icance. From Verdun to Paris the five German armies were in full retreat in the centre, and on the right and on the left were manoeuvring to conform to the retirement. The great battle of the Marne had been fought and won.
So far in this narrative of the battle, beyond the mere mention of the retirement of the German right and centre, no reference has been made as to how, when and why the decision to break off the fight was arrived at. For long the matter was one of some perplexity, and rumours were circulated by the Germans that the Saxon III. Army, in the centre of the line, had failed, and by its failure had frustrated the efforts of the Prussians to the E. and W. Recent German literature has dispelled this unjust legend and has allowed the truth to be known. In the German army, so far back as 1870, liaison officers were a dis- tinctive feature of the Higher Command. These were not mere messengers; they were expected to explain orders, and even, within limits, to give orders in the name of the chief of the General Staff. During the battle of the Marne Supreme Head- quarters were over 100 m. in rear, and the slow working of the wireless apparatus brought it about that by the 8th von Moltke had completely lost his grip of the battle. In these circum- stances a liaison officer Lt.-Col. Hentsch was directed to visit the V., IV., III., II. and I. Armies, and to bring back a clear idea of the situation. Should he find that a retrograde movement had already been initiated on the right wing he was instructed to issue such orders as would close the gap between the II. and I. Armies. During the 8th Lt.-Col. Hentsch visited headquarters of the V., IV., and III. Armies, and spent the night at headquarters of the II. Army. During the forenoon of the following day Gen. von Billow was considerably discon- certed by the passage of British columns over the Marne, and came to the conclusion that a retreat on the part of the I. Army was now inevitable and that his own II. Army must also fall back if its right flank were not to be enveloped. Lt.-Col. Hentsch agreed with the conclusion, and proceeded then by motor-car to the headquarters of the I. Army at Mareuil. Gen. von Kluck was absent at the time, and it was his chief-of-staff, Gen. von Kuhl, with whom the liaison officer conferred. His view of the whole general situation was unfavourable, and he gave it as his opinion that the I. Army must fall back. Gen. von Kuhl pointed out the difficulty of breaking off the fight, and also argued that there was still a fair prospect of defeating the French troops on the Ourcq, but in face of the absolutely full powers of Lt.-Col. Hentsch there was nothing to be done but to break off the action and order the withdrawal of the I. Army towards the north. Gen. von Billow had meanwhile telegraphed to the III. Army on his left notifying his retirement, and that army had no option but to comply with the general retrograde
movement. Thus, by the late afternoon of the gth, the whole right and right centre of the German army was falling back. Supreme Headquarters, in ignorance of the fact, had meanwhile prepared instructions for a continuance of the offensive, but events were too strong for them. It was found necessary to bow to the inevitable, and orders were issued during the evening of the loth for the retreat of all five armies behind the line of the Aisne and Vesle. As to the necessity of renouncing the offensive at this stage opinions are, and will possibly ever remain, at variance. Historical unanimity will, however, probably be reached on two factors the ineptitude of higher " staff work " on the German side and the serious drawback caused by the absence of a general reserve by which the situation might have been restored upon Sept. 9.
The conduct of Gen. von Kluck had not apparently satisfied Supreme Headquarters, and his army was placed " until further orders " under the command of Gen. von Bulow. On the nth some considerable anxiety was felt upon the German side over the possibility of a French thrust against the centre, and a modi- fication was made to the orders issued the previous day, by which the line of the III., IV. and V. Armies was to be Thuizy- Suippes-St. Menehould and E. of the latter place. A new VII. Army was formed from the XV. Corps from the original army of that number in Alsace and the VII. Reserve Corps set free by the fall of Maubeuge. These units were due to reach the area St. Quentin-Sissy about midday on the I2th, and this army was, like the I., also placed under the orders of Gen. von Bulow. The German right wing fell back in good order but in consider- able haste, and on the i2th the J. Army was behind the Aisne on the line Attichy-Soissons-Vailly. The French VI. Army, following up through the forest of Compiegne, crossed the river on the following day, while farther E. of this sector an advanced guard of the British 4th Div. seized the bridge at Venizel and moved forward to the crest of the plateau beyond. On the following morning the battle of the Aisne opened for the British army, and the river line was attacked all along the British front. By nightfall all passages except that at Conde were secured and held, and during the hours of darkness all three corps had con- structed bridges, the crossing being completed in the face of considerable opposition during Sept. 14.
The gap which had existed between the German I. and II. Armies during the battle of the Marne was still unclosed when the position behind the Aisne was taken up by the German right. Once again the persistent British columns scared Gen. von Bulow; but, luckily for him, reinforcements were available, since the VII. Army was now coming to hand, and during the night of the izth and i3th units of the VII. Reserve Corps were hurried down from the neighbourhood of St. Quentin to fill the gap, achieving their object by the narrowest possible margin of time. This reinforcement, which had such an appreciable effect upon the battle of the Aisne, deserves something more than casual mention. On Sept. 9 the VII. Reserve Corps, leaving a detachment at Maubeuge, was ordered N. against the English reinforcements supposed to be advancing from the Flanders coast against Brussels or Antwerp; later in the day a counter order came for it to march S. towards La Fere, as the situation on the Marne was more strained than even that in the north. At 10 A.M. on the i2th, when near Guise, further orders came for the corps to turn off towards Laon at once. The intelligence that arrived from Gen. von Billow was so alarming that Gen. von Zwehl, the corps commander, marched his divisions on all through the night, rested from about 7 to 10 A.M. and then pressed on again. Thus he managed to arrive on the Chemin des Dames by 2.30 P.M. (British time), and little more than an hour later the leading infantry brigade of the British I. Corps was near Moulins, a mile short of the top of the ridge.
The Allied centre did not experience much opposition in the advance, but on the right the German V. Army gave more trouble. As the pivot of the great 'German wheel-back the r61e of the Crown Prince was to mark time, and the duty was carried out with some skill. By the i4th he was on his assigned position. In the temporary deadlock now brought about by the
