The Dall River was full to overflowing, as the spring floods had not all come down, and, so far as the boy could see, it hardly looked like a river at all, but a large flat marsh, with a sluggish current. Over this the boats made good time, sometimes following a blind channel only marked by the trees sticking up out of the water, and sometimes making a short cut over the submerged land. Several times, in the doing of this, the canoes grounded, but the bottom was of mud and no harm was done, the men jumping into the icy water to pull them clear. Higher up the stream, however, the ground rose a little and these short cuts no longer became possible, so that the tortuous channel had to be followed, and as the valley of the Dall is extremely wide and the stream winds from side to side, a long day's traveling did not cause so great an advance. Twenty miles of this irregular going was rarely more than ten or twelve miles of progress, and the eighty-five miles between the mouth of the river and Coal Creek consumed an entire week. Here Rivers called a halt, as he desired to examine the lignite or soft coal of the region. Taking Roger with him, the geologist ascended Coal Creek for a little over a mile above its confluence with the Dall, and there they found a large outcrop of lignite, of which one half the thickness of the seam showed coal of a firm, bright quality. "I should think," said Roger, "that this ought to be more valuable than a gold mine, for Alaska would be all right to live in during the winter, if coal was cheap and easily obtained." "It would make an immense difference," his chief rejoined, "for coal will go further to build up the greatness of a country than any other factor. That was largely the cause of England's rise, and the United States would never be what they are to-day if it were not for the anthracite and bituminous beds of Pennsylvania. If we could lay bare a big anthracite field, Doughty, it would be better for Alaska than all the gold that's ever been struck, though the soft coking coals, used in steel-making, etc., also are extremely valuable." "Perhaps we may," suggested the boy, his eyes alight with the thought of a possible discovery. "I think not," was the conservative reply. "This is the only coal-bearing horizon, and though it does crop up all over the country it is a soft coal strata. You see anthracite is a coal much older and subjected to much greater pressure, so it does not usually occur in the same strata with soft coal." Returning to camp in time to complete the remaining five miles assigned for that day's trip, Rivers told the boy that they would spend the night in Dall City. When a couple of hours later the canoes stopped in front of three or four abandoned prospectors' cabins, the boy was correspondingly disappointed. "Is this Dall City?" he said aloud in disgust.