 out, at any rate in theory. In this working out we provided for the eventuality that our operation at St. Quentin would compel the enemy's leaders to withdraw large reserves from the group in Flanders to meet our breakthrough there.
This eventuality had materialized by the end of March. As soon as we saw that our attack to the west must come to a standstill, we decided to begin our operations on the Lys front.
An inquiry addressed to the Army Group of the Crown Prince Rupprecht elicited the reply that, thanks to the dry spring weather, the attack across the valley of the Lys was already feasible.
The enterprise was now taken in hand by the Army Headquarters Staff and the troops with amazing energy.
On April 9, the anniversary of the great crisis at Arras, our storm troops rose from their muddy trenches on the Lys front from Armentieres to La Bassee.
Of course they were not disposed in great waves, but mostly in small detachments and diminutive columns which waded through the morass which had been upheaved by shells and mines, and either picked their way towards the enemy lines between deep shell-holes filled with water or took the few firm causeways.
Under the protection of our artillery and trench-mortar fire, they succeeded in getting forward quickly in spite of all the natural and artificial obstacles, although apparently neither the English nor the Portuguese, who had been sandwiched in among them, believed it possible.
Most of the Portuguese troops left the battlefield in wild flight, and once and for all retired from the fighting.
It must be admitted that our exploitation of the surprise and of the Portuguese failure met with the most serious obstacles in the nature of the ground. It was only with the greatest difficulty that a few ammunition wagons were brought forward behind the infantry.
Yet the Lys was reached by the evening and even crossed at one point. Here again the decision was to be expected only in the course of the next few days. Our prospects seemed favourable.
On April 10th Estaires fell into our hands and we gained more ground north-west of Armentieres. On the same day our front of attack was extended to the region of Wytschaete. We again stormed the battered ruins of the much-fought-for Messines.
The next day brought us more successes and fresh hopes. Armentieres was evacuated by the enemy and we captured Merville. From the south we approached the first terrace of the great group of hills from which our opponent could see our whole attack and command it with his artillery.
From now on progress became slower. It soon came to a stop on our left wing, while our attack in the direction of Hazebrouck was slowly becoming paralysed. In our centre we captured Bailleul and set foot on the hills from the south. Wytschaete fell into our hands, but then this first blow was exhausted.
The difficulties of communication across the Lys valley which had to be overcome by our troops attacking from the south had been like a chain round our necks. Ammunition could only be brought up in quite inadequate quantities, and it was only thanks to the booty the enemy had left behind on the battlefield that we were able to keep our troops properly fed.
Our infantry had suffered extremely heavily in their fight with the enemy machine-gun nests, and their complete exhaustion threatened unless we paused in our attack for a time.
On the other hand, the situation urgently exacted an early decision. We had arrived at one of those crises in which the continuation of the attack is extremely difficult, but when the defence seems to he wavering. The release from such a situation can only come from a further attack and not by merely holding on.
We had to capture Mount Kemmel. It had lain like a great hump before our eyes for years. It was only to be expected that the enemy had made it the key to his positions in Flanders.
The photographs of our airmen revealed but a portion of the complicated enemy defence system at this point. We might hope, however, that the external appearance of the hill was more impressive than its real tactical val