about 700 feet above the present river level. A part of this sharply defined terrace along the south side of the river, above and below the mouth of Woodchopper Creek, is shown in Plate 1, C. A similar bench at the mouth of Washington Creek is shown in Plate 1, B. In general, the plateau province of interior Alaska has not been glaciated, but locally in some of the higher mountain groups alpine glaciation on a small scale has occurred. In the headwaters of the Charley River, for example, within the limits of the area shown on the accompanying map, Prindle and the writer in 1911 mapped two small areas of morainal deposits. Other areas in the valleys of the Charley and Salcha Rivers were also mapped, and detailed work would doubtless reveal many others. These areas of glaciation are confined principally to the granitic rocks, which constitute the country rock on and near the Yukon-Tanana watershed. One of the best examples of this local alpine glaciation may be seen near the head of the Charley River, in the valley of a creek called by Prindle and the writer Moraine Creek. This creek heads against a mountain 6,284 feet high that lies between two forks of the Charley River and somewhat north of the main Yukon-Tanana divide. The valley has the typical U-shaped glacial form, with a floor about 500 feet wide. At its lower end is a terminal moraine about 400 feet thick, which extends downstream 114 miles into the main valley of the Charley River, where it thins gradually to 100 feet. Here the morainal material extends downstream to an altitude of somewhat less than 3,000 feet. The glaciated valley of Moraine Creek, the confluence of this creek with the main fork of the Charley River, and the morainal material from Moraine Creek that has nearly filled the main valley are shown in Plate 2, A. SETTLEMENTS AND POPULATION The two principal settlements within this district are Eagle and Circle, both on the southwest bank of the Yukon River, the former a few miles west of the international boundary and the latter about 120 miles in an air line downstream. Eagle is a picturesque little settlement built upon a terrace that is well above the high-water level of the Yukon even at times of severe flooding after the spring break-up. It undoubtedly occupies the best town site of the upper Yukon in that it is safe from floods and yet is located alongside a deep channel of the river, which favors the landing and departure of river craft. Eagle is the supply point for the Fortymile, Seventymile, and American Creek mining districts and is also the port of entry in coming downstream from Yukon Territory. The permanent Prindle, L. M., A geologic reconnaissance of the Circle quadrangle, Alaska: U. S. Geol. Survey Bull. 538, pp. 34-35, 1913. summer white population is perhaps 40 people, but the winter population is larger, owing to the fact that some of the miners from the near-by mining districts spend the winter in Eagle. On the Seventymile River and on American Creek, adjacent to Eagle, there are 20 to 30 people engaged in mining, and just upstream from Eagle is a settlement of natives. Circle is at the upper end of the Yukon Flats, upon a great river flood plain. It is the supply point for the Birch Creek mining district, to the south. It has at present a summer population of less than a score of white people, but, like Eagle, it has an augmented winter population, which is derived from the near-by Birch Creek mining district. There are also a considerable number of natives living permanently at and near Circle. Between Eagle and Circle are two smaller settlements, Nation and Woodchopper, the former on the southwest bank of the Yukon about 2 miles below the mouth of the Nation River and the latter on the same side of the river just above the mouth of Woodchopper Creek. Only two men live permanently at Nation, but 8 or 10 others are engaged in mining on the near-by Fourth of July Creek. Similarly at Woodchopper the population consists mainly of the 15 or 20 men engaged in mining and prospecting on Woodchopper, Coal, and Sam Creeks. A few trappers and prospectors also live along the river between Eagle and Circle, but the total white population of this district immediately contiguous to the Yukon, not including the Fortymile and Birch Creek mining districts, is probably less than 100. TRAILS AND TRANSPORTATION The Yukon River is the arterial highway of this region, being traversed by river craft in summer and by dog sleds in winter. Few summer roads have yet been made in this part of Alaska. A wagon road connects Eagle with American Creek and extends on southward as a pack trail to the Fortymile district, another extends out from Circle to the Birch Creek mining district, and during the summer of 1925 a short road was being constructed from Nation up Fourth of July Creek. Much of the freighting is done in winter by horse and dog sleds, but these winter trails are of little use for summer transportation. Supplies for this region, including the Fortymile and Birch Creek districts, are received mainly by way of Skagway and Whitehorse and thence down the Yukon through Canadian territory by river boats. The Alaska Railroad does not serve the upper Yukon region, and the costs of passenger and freight transportation are high. A new summer road has recently been built to connect Fairbanks with summer white population is perhaps 40 people, but the winter population is larger, owing to the fact that some of the miners from the near-by mining districts spend the winter in Eagle. On the Seventymile River and on American Creek, adjacent to Eagle, there are 20 to 30 people engaged in mining, and just upstream from Eagle is a settlement of natives. Circle is at the upper end of the Yukon Flats, upon a great river flood plain. It is the supply point for the Birch Creek mining district, to the south. It has at present a summer population of less than a score of white people, but, like Eagle, it has an augmented winter population, which is derived from the near-by Birch Creek mining district. There are also a considerable number of natives living permanently at and near Circle. Between Eagle and Circle are two smaller settlements, Nation and Woodchopper, the former on the southwest bank of the Yukon about 2 miles below the mouth of the Nation River and the latter on the same side of the river just above the mouth of Woodchopper Creek. Only two men live permanently at Nation, but 8 or 10 others are engaged in mining on the near-by Fourth of July Creek. Similarly at Woodchopper the population consists mainly of the 15 or 20 men engaged in mining and prospecting on Woodchopper, Coal, and Sam Creeks. A few trappers and prospectors also live along the river between Eagle and Circle, but the total white population of this district immediately contiguous to the Yukon, not including the Fortymile and Birch Creek mining districts, is probably less than 100. TRAILS AND TRANSPORTATION The Yukon River is the arterial highway of this region, being traversed by river craft in summer and by dog sleds in winter. Few summer roads have yet been made in this part of Alaska. A wagon road connects Eagle with American Creek and extends on southward as a pack trail to the Fortymile district, another extends out from Circle to the Birch Creek mining district, and during the summer of 1925 a short road was being constructed from Nation up Fourth of July Creek. Much of the freighting is done in winter by horse and dog sleds, but these winter trails are of little use for summer transportation. Supplies for this region, including the Fortymile and Birch Creek districts, are received mainly by way of Skagway and Whitehorse and thence down the Yukon through Canadian territory by river boats. The Alaska Railroad does not serve the upper Yukon region, and the costs of passenger and freight transportation are high. A new summer road has recently been built to connect Fairbanks with |