the German lines.  In front of the British forces, writes an officer of the First Army, before the capture of the Drocourt-Queant portion of the line, ran “line upon line, mile upon mile, of defences such as had never before been imagined; system after complicated system of trenches, protected with machine-gun positions, with trench mortars, manned by a highly-trained infantry, and by machine-gunners unsurpassed for skill and courage.  The whole was supported by artillery of all calibres.  The defences were the result of long-trained thought and of huge work.  They had been there unbroken for years; and they had been constantly improved and further organised.”  And the great canals—­the Canal du Nord and the Scheldt Canal, but especially the latter, were worked into the system with great skill, and strongly fortified.  It is evident indeed that the mere existence of this fortified line gave a certain high confidence to the German Army, and that when it was captured, that confidence, already severely shaken, finally crumbled and broke.  Indeed, by the time the British Armies had captured the covering portions of the line, and stood in front of the line itself, the morale of the German Army as a whole was no longer equal to holding it.  For our casualties in taking it, though severe, were far less than we had suffered in the battle of the Scarpe; and one detects in some of our reports, when the victory was won, a certain amazement that we had been let off—­comparatively—­so lightly.  Nevertheless, if there had been any failure in attack, or preparation, or leadership, we should have paid dearly for it; and a rally on the Hindenburg line, had we allowed the enemy any chance of it, might have prolonged the war for months.  But there was no failure, and there was no rally.  Never had our tried Army leaders, General Horne, General Byng, and General Rawlinson carried out more brilliantly the general scheme of the two supreme Commanders; never was the Staff work better; never were the subordinate services more faultlessly efficient.  An American officer who had served with distinction in the British Army before the entry of his own country into the war, spoke to me in Paris with enthusiasm of the British Staff work during this three months’ advance.  “It was simply marvellous!—­People don’t understand.”  “Everything was ready,” writes an eye-witness of the First Army.[7] The rapidity of our advance completely surprised the enemy, some of whose batteries were captured as they were coming into action.  Pontoon and trestle bridges were laid across the canal with lightning speed.  The engineers, coming close behind the firing line, brought up the railways, light and heavy, as though by magic—­built bridges, repaired roads.  The Intelligence Staff, in the midst of all this rapid movement “gathered and forwarded information of the enemy’s forces in front, his divisions, his reserves, his intentions.”  Telephones and telegraphs were following fast on the advance, connecting every department, whether stationary or still on the move.  News was coming in at every moment—­of advances, captures, possibilities in new country, casualties, needs.  All these were being considered and collated by the Staff, decisions taken and orders sent out.