It was on the front of the Fourth Army, however, in the section from St. Quentin to Gouzeaucourt, that the heaviest blow was planned by the Commander-in-Chief. Here the "exceptional strength of the enemy's position made a prolonged bombardment necessary." So while the First and Third Armies were advancing, on the north, with a view to lightening the task of the Fourth Army, for forty-eight hours General Rawlinson maintained a terrible bombardment, which drove the defenders of the famous line underground, and cut them off from food and supplies. And on the morning of the 29th the Fourth Army attacked. But I have no intention of repeating in any detail the story of that memorable day. The exploit of the 46th Division under General Boyd, in swimming and capturing the southern section of the Canal below Bellenglise, will long rank as one of the most amazing stories of the war. Down the steep banks clambered the men, flung themselves into the water, and with life-belts, and any other aid that came handy, crossed the Canal under fire, and clambered up the opposite bank. And the achievement is all the more welcome to British pride in British pluck, when it is remembered that, according to the German document I have already quoted, it was an impossible one. "The deep canal cutting from the southern end of the canal tunnel ... with its high steep banks constitutes a strong obstacle. _The enemy will hardly attack here._" So writes the German officer describing the line. But it was precisely here that "the enemy" did attack!--capturing prisoners (4,000 of them by the end of the day, with 70 guns) and German batteries in action, before the German Command had had time to realise the direction of the attack.