But it was the tanks which cleared the way, which flattened the wire, and beat down the skill and courage of the German machine gunners, who have taken such deadly toll of British life during the war.

And behind the tanks, protected also by that creeping barrage of the great guns, which was the actual invention of that famous Army Commander with whom I had spent an evening at Valenciennes, came the infantry lines, those now seasoned and victorious troops, for whose "stubborn greatness in defence," no less than their "persistent vigour" and "relentless determination" in attack, General Haig finds words that every now and then, though very rarely, betray the emotion of the great leader who knows that he has been well and loyally served.
There is even a certain jealousy of the tanks, I notice, among the men who form the High Command of the Army, lest they should in any way detract from the credit of the men.

"Oh, the tanks--yes--very useful, of course--but the _men_!--it was the quality of the infantry did it." All the same, the tanks--or rather these tell-tale marks beside this front trench of the Hindenburg line, together with that labyrinth of trenches, cut by the Canal du Nord, which fills the whole eastern scene to the horizon--remain in my mind as somehow representative of the two main facts which, according to all one can read and all one can gather from the living voices of those who know, dominated the last stage of the war.
For what are those facts?
First, the combination in battle after battle, on the British front, of the strategical genius, at once subtle and simple, of Marshal Foch, with the supreme tactical skill of the British Commander-in-Chief.
Secondly, the decisive importance to the ultimate issue, of this great fortified zone of country lying before my eyes in the winter twilight; which stretches, as my map tells me, right across Northern France, from the Ypres salient, in front of Lille and Douai, through this point south-west of Cambrai where I am standing, and again over those distant slopes to the south-west over which the shades are gathering, to St.Quentin and St.Gobain.These miles of half-effaced and abandoned trenches, with all those scores of other miles to the north-west and the south-east which the horizon covers, represent, as I have said, the culminating effort of the war; the last effective stand of the German brought to bay; the last moment when Ares, according to Greek imagination, "the money changer of war," who weighs in his vast balance the lives of men, still held the balance of this mighty struggle in some degree uncertain.

But the fortress fell; the balance came down on the side of the Allies, and from that moment, though there was much fighting still to do, the war was won.
As to the actual meaning in detail of the "Hindenburg" or "Siegfried" line, let me, for the benefit of those who have never seen even a yard of it, come back to the subject presently, helped by a captured German document, and by a particularly graphic description of it, written by an officer of the First Army.
But first, with the scene still before me--the broken bridge, the ruined lock, the splendid trench at my feet, and those innumerable white lines on the far hill-side--let me recall the great story of the six months which preeceded the attack of Sir Julian Byng's Third Army on this bank of the Canal du Nord.
It was on Monday, March 25th, that at Doullens, a small manufacturing town, lying in a wooded and stream-fed hollow not far from Amiens, there took place the historic meeting of the leading politicians and generals of the war, which ended in the appointment of Marshal Foch to the supreme military command of the Allied forces in France.

I remember passing Doullens in 1917, dipping down into the hollow, climbing out of it again on to the wide upland leading to Amiens, and idly noticing the picturesqueness of the place.