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.

Stand to your Arms! By permission of The Sphere.

The incident pictured above occurred when the Turcos were assailed by poison gas and fled from their trenches. When the first fugitives arrived on the outskirts of Ypres, some of our reserves gathered in groups, wondering what had happened and trying to find out what was the matter. Suddenly a staff officer rode up, shouting, "Stand to your arms!" and in a few minutes the troops had fallen in and were marching to the scene of the fight. "Nothing more impressive ran be imagined than the sight of our men falling in quietly and in perfect order amid the scene of wild confusion caused by the panic-stricken refugees who swarmed along the roads, striving to flee as quickly as possible from the German menace behind them."

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.

CHAPTER XXV.

THE BATTLE GLORY OF CANADA.

Every Briton may thank God that the Canadians were where they were when the cloud of poison gas sent the Turcos fleeing in panic to the rear. These sons of the eldest daughter of the Empire, who prior to the war knew little or nothing of the art and discipline of warfare, were now called upon to save the situation when all seemed lost. They, too, had been "gassed;" and though they had not suffered so severely as the French, many of them were already out of action. Against the 3rd Canadian Brigade four divisions of Germans now flung themselves. They were working round to the rear when General Turner threw back his left flank until his line ran roughly thus:—