The moss-plains of the Arctic slopes, brilliant with wild flowers and fragrant with heather and gorse, which surround the Polar Seas the world around, come almost first in the list of objectionable travel. Even in the blazing heat of a summer where the sun shines for twenty-two hours out of twenty-four and the heat is nothing short of tropical, two feet below the surface the spade would touch perpetual frost, a factor of no importance to the branching-rooted tundra moss. Centuries of centuries of growth and decay have created a network of roots, rotten, spongy, and wet, so that walking over it resembles treading on soaked sponges two feet deep. But that nothing may remain to be thought of in the viciousness of that footing, every six or eight inches apart, tufts of grass and moss, known as "niggerheads," hard and round, stick up a foot high. If the unwary traveler decides to walk on these as on the stones of a ford crossing, he finds them slippery and insecure, they turn under his foot, and give him the experience of a twisted ankle; while, on the other hand, if he should endeavor to walk between them he runs a fair chance of tripping upon those hummocks and falling headlong in the oozy moss. Indeed, he can hardly walk at all. [Illustration: THUS FAR WITH THE BOATS, AND NO FARTHER! The beginning of a portage at the summit of a divide; often a road must be cut through the brush. _Photograph by U.S.G.S._] The portage took two days, Rivers making a forced march, and the cook was left at the new camp with the first day's supplies, the carry being to Cache Lake, a large slough which forms the headwaters of the Anaktuvuk River. Early the next morning the rest of the party returned to the old camp, where they had left the canoes, to bring them over to the Lake for their trip down to the Arctic Ocean. Towards evening, as they were returning, and had just ascended a little knoll, Roger hurried up to the chief of the party. "Mr. Rivers," he said, "there seems to be a lot of smoke over there, in the direction of the camp." The geologist looked up sharply and then turned. "Quick, boys," he said, "take the boats to that pond"--the tundra was dotted with small stretches of water--"and anchor them in the middle. The tundra is on fire, and if it's going to spread the boats must be saved. Harry, you go ahead to the camp." He dropped his pack and broke into a run. Bulson, grasping the situation, stuck one of the punting poles deep into the shallow bottom and made fast the canoes to it in the middle of the slough. Then, with the rest of the men he followed the Indian and the chief for the camp. Roger's light weight and his training on the track had made him a good runner, but he did not try to outdistance the other men, and of course Harry was out of sight.