I think of myself as being upon the locomotive, for a run from the lakes to the western ocean. Our starting-point on the lake is 600 feet above the sea. We gain the height of land between the lake and the Mississippi by a gentle ascent. Thirty-one miles out from Duluth we find the waters trickling westward to the Mississippi. There we are 558 feet above Lake Superior. It is almost a dead level, as the engineers say, from that point to the Mississippi, which is 552 feet above the lake at Crow Wing, or 1,152 feet above tide-water. The distance between the lake and Crow Wing is about a hundred miles, and the country is so level that it would be an easy matter to dig a canal and turn the Mississippi above Crow Wing eastward into the waters that reach the sea through the St. Lawrence. The Leaf Hills are 267 feet higher than the Mississippi, and the ascent is only seven feet to the mile,--so slight that the engineers on the locomotive reckon it as level grade. These hills form the divide between the Mississippi and the Red River. Straight on, over the level valley of the Red River, westward to the summit of the rolling prairies between the Red River and the Missouri, the locomotive speeds its way. Gradually we rise till we are 2,400 feet above tide-water,--the same elevation that is reached on the Union Pacific 250 miles west of Omaha. A descent of 400 feet carries us to the Missouri. We wind up its fertile valley to the richer bottom-lands of the Yellowstone, over a route so level that at the mouth of the Big Horn we are only 2,500 feet above tide-water. The Yellowstone flows with a swifter current above the Big Horn. We are approaching the mountains, and must pass the ridge of land that separates the Yellowstone from the upper waters of the Missouri. It lies 950 miles west of Lake Superior, and the summit is 4,500 feet above the sea. Through the entire distance, thus far, there have been no grades greater than those of the Illinois Central and other prairie railroads of the West. Crossing the Missouri we are at the back-bone of the continent, depressed here like the vertebra of a hollow-backed horse. We may glide through the Deer Lodge Pass by a grade of fifty feet, at an altitude of only 5,000 feet above tide-water. Mr. Milnor Roberts, civil engineer, approached it from the west, and this is his description of the Pass:--