"The tract of country above described, which lies north of the Aisne, is well adapted to concealment, and was so skilfully turned to account by the enemy as to render it impossible to judge the real nature of his opposition to our passage of the river or accurately to gauge his strength. But I have every reason to conclude that strong rearguards of at least three army corps were holding the passages on the early morning of the 13th. On that morning I ordered the British forces to advance and make good the Aisne."] [Footnote 124: _Vail._] [Footnote 125: _Brain._] [Footnote 126: _Kon-day´_ (_n_ nasal).] CHAPTER XXX. THE BATTLE OF THE AISNE. When Sir John French came to think over the operations of the day, he was uncertain in his own mind as to the intention of the enemy. Did they mean to make a great stand on the Aisne heights, or were they merely fighting a rearguard action in order to gain time in which to prepare for some new movement? It was most important that the Germans should be made to reveal their plans; so Sir John decided to put the matter to the test on the morrow by making a general advance. All night long the engineers were hard at work strengthening the new crossings and repairing the old bridges, so that they would bear the weight of heavy guns and lorries. The infantry were no less busy, digging themselves in on the ground which they had won the previous day. The real attack was to be made by the First Army Corps, under Sir Douglas Haig, and we will now follow the fortunes of his command. On September 13 he had fought his way northward for about two miles, and was now holding the hillsides and the woods around the village of Troyon, directly to the north of Bourg. You must not confuse this Troyon with Fort Troyon, which was mentioned in Chapter XXVII. Fort Troyon is an outlying fort of Verdun, on the right bank of the Meuse; the Troyon of which I am now speaking is a tiny village about three miles north of Bourg, on the Aisne. To the north of Troyon are steep wooded slopes, and to the west is an undulating and densely-wooded country, rising towards high hills. Dense woodlands lay between Troyon and the position which the First Corps now held.