wall, the heavy, jarring crash of a Winchester roaring from the bush, to be repeated at close intervals which were as regular as the swing of a pendulum. A round, dark object popped up over the flat roof line and the cross-legged man on the ground threw a gun to his shoulder and fired, almost in one motion. The head dropped from sight as the marksman slid another cartridge into the magazine and waited, ready to shoot again or to exchange weapons with his kneeling friend.
The runner leaped on at top speed, but he automatically counted the reports behind him and a smile flashed over his face when the count told him that the second rifle was being used. He would have known it in no other way, for the spacing of the shots had not varied. Again the count told of the second change and a moment later another extra report confirmed his belief that the roof was being closely watched by his friends. A muffled shout came from the building and a spurt of fire flashed from the loophole, but toward the sky and he fancied he heard the sound of a falling body. Far to his left jets of flame winked along a straggling line, the reports at times bunched until they sounded like a short tattoo, while be hind him the regular crashing of an unceasing Winchester grew steadily more distant and flatter.
His breath was coming in gulps now for he had set himself a pace out of keeping with the habits of years and the treacherous sand made running a punishment. During the last hundred feet it was indeed well for him that Johnny shot fast and true, that the five-hundred grain bullets which now sang over his aching head were going straight to the mark. He suddenly, vaguely real-
