By the time that this work was completed the flames were within three miles of the camp. For a breadth of more than twice that distance the grass was blazing furiously. Lurid red tongues of flame licked the dark cloud of smoke that overhung the devouring elements. Already the air was reeking with pungent fumes. Grey ashes, caught by the strong wind, whirled past the anxious watchers or dashed lightly into their faces. Dark shapes, silhouetted against the red glare, tore madly from the advancing fire. They were the denizens of the grass lands flying for their lives. Undeterred by the water the panic-stricken animals plunged into the river, some of them in their terror frantically pawing the sides of the anchored boats. "Dash it all!" muttered Denbigh. "Wish to goodness I'd cleared another hundred yards of the scrub. We'll be shrivelled up with the heat. There's still time." Calling to his handful of men the sub ran into the open. This time, since the inner circle offered no grip to the flames, they could work without fear of the fire getting the upper hand. In the midst of their preparations Denbigh heard a hoarse shout. Stumbling towards him, half-enveloped in the haze that was the forerunner of the roaring furnace, were two men. One fell, picked himself up, and staggered after his companion. Outlined as they were against the ruddy glare it was impossible to distinguish them, but as the British seamen ran forward to bear them into safety the men raised their arms appealingly. "Help, kamarade, help!" they cried. "Germans!" ejaculated Armstrong. "Where are our fellows?" Denbigh could not give an answer. A glance in the direction of the wall of fire, now less than a quarter of a mile distant, told him that life was impossible in front of that barrier unless the fugitives were already in sight. But they were not The sub set his jaw tightly. "Where are the others--and the British seamen?" he asked in German of one of the men. The other was beyond speech. "All gone! All gone!" replied the German. "There's another, sir!" exclaimed a petty officer. "Come on, stick it!" shouted half a dozen lusty voices in encouragement. The third man was evidently in the last stages of exhaustion. He was gasping for breath as he ran, but the hot acrid air was fast choking him. He flung his arms above his head and pitched upon his face, with the burning embers dropping all around him. A cloud of eddying smoke enveloped him. Then a gust of wind cleared the pall of vapour. The wretch was writhing. His clothes were smouldering as he lay helpless in the withering grass. With a bound Denbigh cleared the shallow trench, and bending low rushed through the smoke. Burning ashes stung his face. What air he took in through his nose felt pungent and suffocating. The heat seemed to gnaw into his eyes.