Gold Region." Laramie Plains are a level of similar interest. This level is a justification of the Spanish name of the system,- Sierra Madre, or Mother-Range. It is one of a group of mothers occurring along the axis of the Range, out of whose loins come the grand rivers which irrigate the Continent. From the Plains of the South Pass, and the vast ranges on whose summit the plateau is upborne, flow the Missouri and the Yellowstone to the easterly; the Snake, or principal fork of the Columbia, to the westward; and in a direction south by westerly the Green, or main branch of the Colorado River. Either by themselves or their cañons and valleys, which radiate towards one common centre in the Plains of the Pass, these rivers facilitate communication between the Mississippi and the Great Salt Lake basins, offering a series of nearly connected galleries or grades rather to the revision than to the reconstruction of the civil engineer. The Laramie Plains form another level, important for the same reasons, if not in the same degree. The level and its inclosing mountains form a reservoir for far less voluminous and extensive streams than those rising out of the South Pass plateau, but offer better opportunities for the study of the phenomena of the system than if their own were more complicated. The mountain mesa which has the Laramie Plains for its upper surface, is almost cinctured by the North Platte River. The South Platte has its origin in South Park; its net-work of tributaries may almost be said to inosculate on the north side with those running into Middle Park for the formation of the Blue Fork of the Colorado; the Blue Fork receives another system of tributaries running southerly from North Park, and this system again interpenetrates that of the tributaries

running northward to compose the North Platte in the area of the same Park. Behind that grim range of bare, black mountains which form the southern wall of the Laramie Plateau, the North Platte is winding in a general westerly direction out of the snowpeaks which nurture its infancy. Eighty miles west of the Laramie Plains summit level, it makes an abrupt bend to the north, and thence preserves this direction to the western butment of that noble range which forms the northern wall, taking in, near this corner, the Medicine Bow Creek, which has descended from a magnificent congeries of snow-peaks, to be climbed by us on the morrow, and has followed a higher terrace of the same slope as the North Platte across the entire west side of the mesa. A step further on, the North Platte receives the Sweetwater from the west, and, passing around a bastion of the Wind River system, turns nearly due east to enter the lower Plains near Fort Laramie, receiving en route innumerable further tributaries, all of which rise from the north slope of the Wind River system, excepting the Laramie River itself. This latter stream is formed by the junction of two forks, the Big and Little Laramie, both of which rise out of the Black Mountains, on the plateau's southern boundary, and traverse it completely from south to north, uniting nearly in its

centre.

- A careful examination of the best Government maps of this region will enable the reader to follow this description, and get an idea of the contour of the Laramie mesa, which may serve as the key to all other formations of the kind, including the Plains of South Pass and the three great parks south of Laramie. Upon such nodal points as these, all the internal

river systems of the Continent are centred. Their contour and position are the important facts of the range to the theoretical, the all-important ones to the practical student of physical geography.

Big and Little Laramie, where we crossed the Plain, flow nearly parallel and about fourteen miles apart. Their width, at the bridges maintained by the Overland Route, is about thirty or forty yards. Their banks, but especially those of the latter branch, are enameled with flowers of a brilliancy unequaled, but of titles unknown in my experience. One variety

was a scarlet vivid as flame, and at a distance resembled a salvia. The leguminaceae were represented by several plants bearing the richest mauve and purple blossoms; besides which I noticed some flowers seemingly allied to the larkspur, of a deep-blue shade, and sparingly interspersed among the profusion of the others. The sun was just on the western verge of the plateau as we reached Little Laramie; and the effect of his level rays upon the exquisite cool verdure of the grass, with all these brilliant flowers dashed in for the high tones, was something out of which to manufacture peaceful memories for a lifetime.

During the next seventeen miles the ground gradually grew less even; but the general characteristics of the plateau were preserved until twilight gave way to starlight, and we arrived at the station of Cooper's Creek. Here the moon rose, and revealed to us one of the loveliest little dells in all the Rocky Mountain scenery. Along the bottom of a shallow depression ran, crystal-clear and icy cold, a small stream, rising from the same Black range as the Laramie, and belonging to one of three classes which

abound in this immediate vicinity: the streams which lose themselves upon the Plain in "sinks," or lakes without outlet; those which penetrate the Black range to join the North Platte immediately; and those which flow thither indirectly, by emptying into Medicine Bow. For these three systems, the terrace including Cooper's Creek forms a nodal point on the small scale; to which of them the creek belongs, I am not positive. We ate our supper from the box of private stores, sitting dappled with the moon-shadow of the luxuriant cotton-woods which embowered the creek; and listening to its tuneful gurgling, or watching the silver flash of ripples break across an umber pool of shade, we could have forgotten that this was not the end of our wanderings.

The hoarse "All right!" of the driver startled us from our lotus margin. We had a great deal more before us; so we arose to shake the crumbs from our beards, and the romance from our souls. We turned back one lingering glance at the paradise of Laramie Plains. Far off we heard the shrill yelp of the coyote; and as far, a silver spark went shooting across the shadow of a grassy terrace, with that electric swiftness which denotes the antelope. The whole great level was powdered with silvery mist. The moonlight seemed to lie on the nearer grass in silvery globules. Moonlight was .tangled into the texture of the grossest things. The ragged cotton-wood bark by the creek looked like strips of silver foil; the bleak station-house was soaked in a solution of romance, and might have been let for a palace to Rasselas ; there was antiquity and a sort of Gothic strength about the company's stables; while the very mules of the new relay seemed touched by the divinity of

the hour, and became hallowed, or moon-mellowed mules, who might have walked into the traces out of some old Italian "Flight into Egypt," or " Adoration of the Magi."

With a sigh at turning our backs upon this lovely view, we drove across the creek, and immediately entered a rolling country. The transition between the general level of Laramie Plains and the intricately convoluted tract just west of Cooper's Creek, is almost as abrupt as the threshold of a door. The simple passage of a stream which does not wet our hubs, takes us at once into the view of an entirely new type of landscape. We are now, strictly speaking, out of the Laramie Plateau, and beginning to ascend toward Elk Mountain and the head of Medicine Bow, by the foot-hills of the range including them. We were entering the extremity of the Black range, which had imperceptibly swung round nearly a whole quadrant while we were crossing the Plains, to blend with the Elk Mountain range as we ascended. The evening had been bracing, but not unpleasantly sharp, upon the Plains. Ascending from an elevation of eight thousand feet, however, a man is not compelled to go very far for cold weather. We had not climbed an hour among the gray, cerebral convolutions of this tract, before the cold became intense enough, not only for overcoats, but for all the blankets we could wrap in. I was quite benumbed upon my favorite seat at the driver's side; and he himself suffered severely under a heavy-caped coachman's coat of pilot-cloth, his fingers aching and stiffening around the lines inside Indian mittens of thick buckskin. Yet we could scarcely have chosen a more favorable season to cross the range, and this