Thirty-seven miles below Sans Sault rapid and twenty-one miles above Fort Good Hope, Beaver river joins on the west, but as Mr. Ogilvie continued only on the east side he saw only its mouth, which appeared to be about one hundred yards wide. An Indian with him said that it took its name from the number of beavers formerly found on it. This stream rises in the mountains, but does not seem to be of any importance. Somewhat less than two miles from Beaver river, and only a short distance above the Ramparts, a river flows into the Mackenzie on its west side. Mr. Ogilvie saw it only across the river, but it appeared to be about two hundred yards wide at its mouth. All he could learn about it at Fort Good Hope was that it came from far up in the mountains. THE RAMPARTS OF THE MACKENZIE. Mr. Ogilvie remarks in his report that in the more southwesterly part of the country the Ramparts would be called a “Cañon.” Here, for a distance of seven miles, the river runs between perpendicular and occasionally overhanging walls of rock. At the upper end they rise fifty or sixty feet above the water, but their height increases towards the lower end, at which point they are not less than one hundred and fifty feet above water. At the upper end the cañon is not more than half a mile wide, but its walls gradually expand three miles down, and the width gradually expands to nearly a mile at the lower end. Sir Alexander Mackenzie when passing through sounded at its upper end, and found three hundred feet of water, which accounts for the fact that, although the cañon is so narrow, the current is not perceptibly increased. According to Mr. McConnell’s description:—“The Ramparts form one of the most interesting features of the Mackenzie. For some distance above, the river is expanded beyond its usual size, but here suddenly contracts to about five hundred yards in width, and bending to the east runs for three or four miles between vertical walls of limestone and shale. At the upper end of the gorge the bounding cliffs are a hundred and twenty-five feet in height, but increase towards the lower end to about two hundred and fifty feet. The current is steady and runs at the rate of four or five miles an hour. In high water there is no sign of a rapid, but in low water a considerable fall occurs near the head, and it is only with difficulty that York boats are taken up. The Ramparts are frequently the scene of great ice jams in the spring and the dammed-back water is stated to have risen on one occasion over a hundred feet, and on its recession left a boat stranded on the heights above.” FORT GOOD HOPE.