CHAPTER XXIV.

THE POISONOUS CLOUD.

While the Germans were fiercely shelling Hill 60 the tide of war rolled along the Ypres Salient, which has so often figured in these pages. The Gaspipe Officer already quoted says: "The old Ypres salient was such a silly thing. Imagine for a moment one of those old Greek theatres, semicircular. All the way round the Germans were on the top row of seats, and we were only halfway up. They could see everything that we were doing, while we, hemmed in, had to trust to aeroplanes. And down on the floor of the theatre stood Ypres, through which, or by which, nearly every road to the salient passed."

If you look at the diagram on page 189, you will see how we were holding the salient on the morning of 22nd April. Our lines ran in a semicircle from Steenstraate, on the Yser canal, about four and a half miles to the north of Ypres, right round to the Ypres-Comines canal, about two miles south of the city. Nowhere was the salient more than four and a half miles across; every part of it, including Ypres itself, was, therefore, within range of the enemy's big guns. As the Gaspipe Officer tells us, the Germans held the higher ground, and were thus in a very favourable position for sweeping all parts of the salient with their fire. All the roads to the outer rim of the salient spread out from Ypres like the spokes of a wheel. Our supply and ammunition columns were, therefore, under fire the moment they entered or passed by the city.

The British forces had greatly increased since those days of terrible trial in the preceding October and November, when, with never more than 150,000 men, we had beaten back the furious onrush of at least half a million Germans, and had blocked for ever the coveted road to Calais. We had now some 500,000 men at the front, and we felt, after our great assault at Neuve Chapelle, that we had the upper hand of the enemy, and that henceforth the attack was with us and the defence lay with him. Before, however, he sank into this secondary position he meant to make another desperate effort to reach the Channel ports. This long and fierce struggle, which I am now about to describe, is known as the Second Battle of Ypres.

Look again at the diagram. The Allied line from Steenstraate to Langemarck was held by Turcos and Spahis, French colonial troops from Algeria. Continuing the curve for 5,000 yards was the Canadian Division, consisting of three infantry brigades, in addition to artillery brigades. The first infantry brigade was in reserve, the second (8th and 5th Battalions) lay on the right, and the third (13th and 14th Battalions) on the left, next to the French. The whole division was commanded by General Alderson; Brigadier-General Turner commanded the 3rd Brigade, and Brigadier-General Curry the 2nd Brigade. The trenches, which the Canadians had taken over from the French, were badly made and very wet, and could only be improved with difficulty, as the dead had been buried in the bottoms and the sides. The 28th Division continued the line to the south-east corner of Polygon Wood, where Princess Patricia's Own were stationed. From the wood to Hill 60 the remainder of the salient was manned by the 27th Division.

Though the salient was well known to be a source of weakness, it was not strongly held by the Allies at this time. Probably the Germans were aware of the fact, for suddenly they launched a furious and determined attack against the forces holding it. The only warning which the Allies received was on the 20th, when the guns of the enemy began to bombard Ypres. Huge shells from the heaviest of guns fell in the streets, which were then thronged with citizens and our own reserves. Fifteen little children were killed at their play, and a number of the townsfolk perished amidst the ruins of their houses. Our generals understood at once the meaning of this bombardment. It was meant to block the roads to our lines on the salient, and make the work of sending forward supplies and ammunition very difficult, if not impossible. It was not meant to embarrass us at Hill 60, for we had free roads leading to that position from the west. It could only be the forerunner of an attack on that part of the salient extending from the Yser Canal to the Menin road--that is, on the portion held by the French Colonials, the Canadians, the 28th Division, and Princess Pat's. Our generals viewed the bombardment with anxiety; they knew that we were ill prepared to meet the attacks which were soon to follow.

Thursday, 22nd April, was a peaceful day, warm and sunny. A light, steady wind was blowing from the north-east. About five in the evening an aviator reported that he had seen a strange green cloud, higher than a man, surging across the open ground from the German lines towards the French trenches. It was the deadly poison gas chlorine, which when taken into the lungs sets up acute bronchitis and causes its victims to die in horrible agony. At every fifty feet or so along the German front a battery of twenty retorts had been established. The gas from these retorts had been pumped at high pressure into huge reservoirs from which pipes ran to the front trenches. When the nozzles were turned on, the deadly gas rushed out, and was carried by the wind towards the French lines. Special respirators had been served out to the German soldiers, who were waiting in readiness to take advantage of this foul blow. Never before had poison gas been used in this manner on the battlefield. The Germans were about to sound the deepest depths of their infamy and try to poison those whom they could not beat in fair fight.

Onward rolled the greenish-white cloud, across fields, through woods, and over hedgerows. Soon the Turcos in their trenches were gasping and choking and suffering unspeakable tortures. They were brave men; there was no mortal foe they were not ready to engage; but this creeping cloud that struck them down in agony was a devilish magic which they could neither understand nor resist. A horrible, unreasoning terror took possession of them, and they ran. Back they fled through the dusk, a coughing, blinded crowd, leaving behind them hundreds of their comrades gasping out their lives or lying dead with blue faces and frothy lips. Some of them fled due south towards the Langemarck road, and in the early darkness came upon the reserve battalions of the Canadians, who gazed in amazement upon their wild dark faces, their heaving chests, and speechless lips. Soon the Canadians began to feel the effects of the gas, and many of them were afflicted by a deadly sickness.

A great breach, four miles wide, now yawned between Steenstraate and Langemarck. On the left of the Canadians there was a huge rent, through which the Germans were preparing to advance, while their artillery pitilessly whipped the fugitives onward. The situation was dangerous in the extreme. Ypres appeared to be within the Kaiser's grasp. The Canadians were unsupported on their left; the French trenches were choked with dead and dying; and fifty French guns were in the hands of the enemy. In vain the officers strove to rally the fleeing Turcos. Meanwhile a great mob of Germans pushed through the wall of gas which was now breaking up into patches behind them, and rushed on towards Ypres. Only two miles of open country now separated them from the city of their desire.