The walls of the cañon are nearly a mile in length and are perpendicular columns of rock. The center of this cañon expands into a large basin full of whirlpools and eddies. The waters, white with foam, tear through this narrow passage of rock at the rate of six or seven miles an hour, with a roaring that can be heard at a great distance. At the northern end of the cañon the rushing river widens again, but for four miles it seethes, foams, and falls in cascades. The luggage was sent round by portage, and Schwatka prepared to shoot his raft through the rapids. Once started, the men could not control or guide the raft at all, but left it to work its own way. This it did very successfully, though many times they thought it would surely be dashed in pieces. After the rapids were passed, the men drew the sturdy raft ashore, and found that it needed but few repairs. While some of the men were engaged in mending the raft, the others fished. Schwatka found this the best fishing ground on the entire river; in a short time between four and five hundred fine grayling were caught with rod and fly. The raft was ready for use again by July 5, and on that day Schwatka and his party started once more down the Yukon, and soon passed through the last lake they were to encounter. After this the river became wider and was dotted with islands; then the site of old Fort Selkirk came into view. [Illustration: TANANA STATION, RIVER YUKON, IN WINTER.] Fort Selkirk was built in 1850 by the Hudson Bay Trading Company for a trading post with the Indians. But the Chilkats wanted the furs from the interior for themselves; so they gathered a war party together, descended the Yukon river to Fort Selkirk, burned the building, and carried off the goods. Now all that remains of Fort Selkirk is a group of three old chimneys. Schwatka camped at this spot several days. Near the river bank he came upon a burial ground of the Ayan Indians, who inhabit this part of the country. A fence of rough boards, bound together by willows, is built around each grave. Above the grave there stands a long, light pole about twenty feet high, with a piece of colored cloth hanging from the top. Near the grave, but outside the inclosure, stands another pole of about the same height. To the top of this second pole is fastened a rude carving of a fish, duck, goose, bear, or some other animal or bird. These poles are called totems. They represent the most clever workmanship of these Indians, and are collected and sold as curiosities. Some of the carvings are very old and display remarkable skill. No one knows exactly what these totem poles mean, as the Indians are unwilling to talk about them, but they are supposed to indicate in some way the history of the buried person or of his tribe. The Indians do not make totem poles any more, but they carefully preserve those which they already have.