For nearly an hour they advanced at a fast rate of speed, Sandy and Dick changing off advance guard with Toma. Then they entered a long ravine, crested with spruce and jackpine. As yet no sign of the man who had shot the corporal appeared. Then, without warning, from the brow of the ravine, puffed the smoke of a rifle. A bullet fanned Dick’s cheek, and he paused and fired at the distant smoke at the top of the ravine.
“Mush! Mush!” shouted Sandy to the dogs, cracking the long whip.
The dogs responded nobly, drawing the sled, carrying the wounded officer, so fast that the boys could hardly keep up.
Again the hidden rifle cracked from the top of the ravine. This time one dog gave a sharp yelp, leaped into the air and fell kicking his last in a tangle of harness.
“He’s killed a dog!” cried Dick angrily. “Quick, get him out of the harness so we can go on.”
The three remaining huskies were growling and snarling in a mess, and it was some minutes before Sandy and Toma could straighten them out, cut the dead dog from his harness and start on again. Meanwhile Dick emptied his rifle at the brow of the ravine, taking a chance on hitting whoever was skulking there with such deadly intent.
On their way again, the fast moving sled proved an elusive target for the sharpshooter. He shot three times without effect. Swiftly they neared a point where the ravine widened out into a low walled valley, which was almost barren of vegetation. Once on this clear space they would be safe, for there was no cover within rifle range for the man who was dogging them.
Dick and Sandy were almost on the point of giving a shout of triumph when the hidden rifle cracked again and another dog dropped in the harness. The sled stopped, and once more the excited dogs got themselves in a bad mix-up. At the mercy of the mysterious and deadly rifle, the boys attacked the tangled harness and dogs.
CHAPTER XVIII
A HUNGRY PACK
Scarcely had they cut loose the fallen dog when the rifle sounded again and the lead dog dropped to his haunches, failing to rise again. Dick put the dog out of misery with a shot from his rifle, then turned to Toma and Sandy.