Five seconds later there was a terrific explosion in the center of the listening post. Numa gave a nervous start and attempted to break away; but Tarzan held him and, leaping to his feet, ran forward, dragging Numa after him. At the edge of the post he saw below him but slight evidence that the position had been occupied at all, for only a few shreds of torn flesh remained. About the only thing that had not been demolished was a machine gun which had been protected by sand bags.
There was not an instant to lose. Already a relief might be crawling through the communication tunnel, for it must have been evident to the sentinels in the Hun trenches that the listening post had been demolished. Numa hesitated to follow Tarzan into the excavation; but the ape-man, who was in no mood to temporize, jerked him roughly to the bottom. Before them lay the mouth of the tunnel that led back from No Man's Land to the German trenches. Tarzan pushed Numa forward until his head was almost in the aperture, then as though it were an afterthought, he turned quickly and, taking the machine gun from the parapet, placed it in the bottom of the hole close at hand, after which he turned again to Numa, and with his knife quickly cut the garters that held the bags upon his front paws. Before the lion could know that a part of his formidable armament was again released for action, Tarzan had cut the rope from his neck and the head bag from his face, and grabbing the lion from the rear had thrust him partially into the mouth of the tunnel.
Then Numa balked, only to feel the sharp prick of Tarzan's knife point in his hind quarters. Goading him on the ape-man finally succeeded in getting the lion sufficiently far into the tunnel so that there was no chance of his escaping other than by going forward or deliberately backing into the sharp blade at his rear. Then Tarzan cut the bags from the great hind feet, placed his shoulder and his knife point against Numa's seat, dug his toes into the loose earth that had been broken up by the explosion of the bomb, and shoved.
Inch by inch at first Numa advanced. He was growling now and presently he commenced to roar. Suddenly he leaped forward and Tarzan knew that he had caught the scent of meat ahead. Dragging the machine gun beside him the ape-man followed quickly after the lion whose roars he could plainly hear ahead mingled with the unmistakable screams of frightened men. Once again a grim smile touched the lips of this man-beast.
"They murdered my Waziri," he muttered; "they crucified Wasimbu, son of Muviro."
When Tarzan reached the trench and emerged into it there was no one in sight in that particular bay, nor in the next, nor the next as he hurried forward in the direction of the German center; but in the fourth bay he saw a dozen men jammed in the angle of the traverse at the end while leaping upon them and rending with talons and fangs was Numa, a terrific incarnation of ferocity and ravenous hunger.
Whatever held the men at last gave way as they fought madly with one another in their efforts to escape this dread creature that from their infancy had filled them with terror, and again they were retreating. Some clambered over the parados and some even over the parapet preferring the dangers of No Man's Land to this other soul-searing menace.
As the British advanced slowly toward the German trenches, they first met terrified blacks who ran into their arms only too willing to surrender. That pandemonium had broken loose in the Hun trench was apparent to the Rhodesians not only from the appearance of the deserters, but from the sounds of screaming, cursing men which came clearly to their ears; but there was one that baffled them for it resembled nothing more closely than the infuriated growling of an angry lion.
And when at last they reached the trench, those farthest on the left of the advancing Britishers heard a machine gun sputter suddenly before them and saw a huge lion leap over the German parados with the body of a screaming Hun soldier between his jaws and vanish into the shadows of the night, while squatting upon a traverse to their left was Tarzan of the Apes with a machine gun before him with which he was raking the length of the German trenches.
The foremost Rhodesians saw something else—they saw a huge German officer emerge from a dugout just in rear of the ape-man. They saw him snatch up a discarded rifle with bayonet fixed and creep upon the apparently unconscious Tarzan. They ran forward, shouting warnings; but above the pandemonium of the trenches and the machine gun their voices could not reach him. The German leaped upon the parapet behind him—the fat hands raised the rifle butt aloft for the cowardly downward thrust into the naked back and then, as moves Ara, the lightning, moved Tarzan of the Apes.