The daylight was growing apace. Step by step the dawn mounted in the heavens, the shadows fled from the valleys, and the bush became alive with the songs of thousands of birds.

And then they witnessed a tragedy such as neither ever wished to see again. The native sentry, who had fallen asleep upon his post, was led with trembling knees and shaking lips before the major in command, who, after a few savage questions, hurled at the man like scraps of meat to a dog, sentenced him to be shot. And then and there the sentence was carried out before their eyes.

After that the major gathered his men together and divided them into two parties, evidently with the idea of searching both ends of the ravine. And now occurred one of the most strangely dramatic things of which we have to tell.

The commanding officer was giving final instructions to his officers and sergeants. He stood upon a large boulder. His subordinates were listening to his words with silent respect. He spoke in a husky, guttural voice, from time to time shivering as if he suffered from fever. Suddenly, he flung both hands above his head and uttered a piercing cry. Simultaneously, there came the sharp report of a rifle from beyond the ravine, and the German major fell forward on his face.

[CHAPTER XII—The Mystery of the Running Man]

On the instant the greatest disorder prevailed. As at a stroke the iron discipline of Potsdam vanished, and despite his uniform and training, and the curses of the German non-commissioned officers, the Cameroon native became the untutored savage once again.

In the panic of the moment the native soldiers took to their heels, evidently under the impression that they had been surprised by a British force. And, as they ran, shots rang out repeatedly from somewhere in the midst of the shrubbery that grew on the farther side of the gorge.

There was no question that the invisible man who commanded the ravine from his hiding-place upon the mountain-side was a marksman of repute. He fired in haste at running figures, and more than once his bullets found their mark. The German-trained soldiers vanished as by a conjuring-trick, disappearing round an angle of the gorge.

All this had happened in the space of a few seconds. Harry, taking his field-glasses from their case, scanned the mountain that overtopped the ravine, endeavouring to discover the form of the mysterious and terrible marksman who had created such alarm.

Nowhere was any living soul to be seen. The mountain-side was as silent as the grave. In the forest itself, hundreds of birds welcomed the dazzling sunlight with the gladness of their songs.