To the northward of Mackinac, Lake Superior discharges into Lake Huron through the Sault Sainte Marie Strait, the "Leap of St. Mary." This strait of St. Mary is a winding and most beautiful stream, sixty-two miles long, being a succession of expansions into lakes and contractions into rivers, dotted with pretty islands and having some villages on the banks. The chief attraction is the Sault, or "Leap," which is a rapid of about eighteen feet descent, the navigation being maintained through capacious modern systems of locks and ship canals provided by both the United States and Canada. To the westward is the great Lake Superior, the largest fresh-water lake on the globe, three hundred and sixty miles long and covering thirty-two thousand square miles, with a coast-line of about fifteen hundred miles. It is elevated about six hundred feet above the ocean level, and has a depth averaging one thousand feet. Nearly two hundred rivers and creeks flow into it, draining a region of a hundred thousand square miles. There are a few islands in the eastern and western portions, but all the centre of the lake is a vast unbroken sheet of water, and generally of a low temperature, the deeper waters being only 39° in summer. The early French missionaries, who were the first explorers, told their interesting story of Lake Superior in Paris in 1636, and in their published account speak of its coasts as resembling a bended bow, of which the north shore makes the arc of the bow, the south shore the chord, and the great Keweenaw Point, projecting far from the southern shore, represents the arrow. Superior has generally a rock-bound coast, displaying impressive beauties of scenery, particularly on the northern shore, where the beetling crags and cliffs are projected boldly into the lake along the water's edge. This northern coast is also much indented by deep bays, bordered by precipitous cliffs, back of which rise the dark and dreary Laurentian Mountains. There are also rocky islands scattered near this portion of the coast, some presenting vast castellated walls of basalt and others peaks of granite, elevated a thousand to thirteen hundred feet above the lake. Nowhere upon the inland waters of North America is there grander scenery.