of white immigration to this region, the buffalo has existed on this side of the Rocky Mountain watershed. At present his furthest range reaches only within the lower line of ridges on the eastern slope of the system, individuals of the tribe being occasionally shot in the cañons of Colorado, but none having been known by the present inhabitants to pass the first snow-range. Several old hunters and trackers of large experience, whose acquaintance I formed in Colorado, believed in the existence of a separate species of bison, peculiar to the mountains, characterized by greater size than the Plains animal, and still further differing from those congeners in their stationary habits, remaining in the mountain fastnesses all the year round, instead of emigrating southward with the approach of winter. Furthermore, the habits of this supposed species were solitary. They were never met in herds, and in couples only during the marital season. At one time I was almost led by the accounts which I received into the belief that the animal described by hunters who had killed specimens in the range, was neither more nor less than a stray from that exceedingly interesting family which finds its usual habitat in the barrens of a much more northerly portion of our Continent; namely, that connecting link between the Bovidae (already, as represented by the bison, manifesting a wide departure from the typical bull in this same direction) and the sheep (as compromised toward the bison in the "Bighorn "), the musk-ox, or Ovibos Moschatus. Remains of this animal have been found in tertiary beds of the Continent much further south than Denver; but having no specimens, and only an unscientific report to proceed upon, I was obliged to abandon my

hypothesis in view of the fact that no living individual has been found within the memory of man further south than 60° lat. N. I know of no country where a given type of animals has its divisions shaded into each other by so complete a series of delicate gradations as prevails among the hollow-horned ruminants of North America, taking them in their order from the domestic sheep to the domestic cow, through the bighorn, the ovibos, and the bison. Indeed, either of these three suggests one type nearly as much as another.

The indications of the bison's former passage of the Rocky Mountains lie strewn over a wide area. In several places along our route within the Green River link, I observed skulls of this tribe in excellent preservation. In some instances the horns were as entire as on the day that the animal was killed; the apices being only slightly rounded. Some of them were in the argillaceous deposit of overflows from the tributaries of the Green; others projected out of sand dunes; and several lay entirely exposed to sight on the denuded and water-worn pebbles of the wide tract above referred to.

The fact of our gradual approach to Salt Lake was now indicated increasingly at every stage of our progress. We found in every spring the evidence of a former submersion of this entire tract beneath the waters of a stagnant inland sea. Salt Lake remains as the last vestige of a period when the vast estuary which set northwesterly from the present boundaries of the Gulf of Mexico to the plateau of Snake River, was caught by a sudden upheaval of transverse ranges which forever shut it up from its connection with tide-water, and cut it up, by a series of colossal walls

or dams, into a number of minor saline lakes, in all respects but size exactly corresponding to the present Great Salt Lake of Utah. The theory of this formation, fortunately for the student, has a perfect paradigm in that remarkable reservoir; and in the proper place I shall show how admirably, yet minutely, it explains itself and many neighboring tracts, which, but for its survival from the period when it was only one of many, might prove obstinate problems to the geologist and physical geographer.

At Rock Point we encountered, for the first time since leaving the Nebraska Plains, what in this region and at this season was an unusual phenomenon, a drenching shower of rain. I would have been glad to have caught some of the sky's bounty, had any receptacle been at hand, for the spring water found at long intervals on our route was exceedingly nauseous. The alkaline water on the eastern side of the mountains was bad enough, but this was many grades beyond. Much of the soda and potash in the former was drawn from vast beds of feldspar, a mineral which seems in this climate peculiarly susceptible to decomposition, and in many places may be seen rotting out of the granite formations into an impalpable pow

der.

The mineral constituents of the springs we now encountered were much more varied and abundant, embracing chloride of sodium, sulphur and sulphide of hydrogen, iron in the form of chromate and peroxide, carbonates of potash and soda, sometimes associated with bromine and iodine. The source of these was no contemporary decomposition, but the beds deposited through an unmeasured period by stagnant bodies of salt water, cut off from all means

of escape save evaporation and a gradual deposit from a super-saturated solution.

The night after leaving Rock Point was the wildest in which I ever travelled. The heavens were pitchy black, except in patches where now and then the moon succeeded in struggling through a thinner layer of clouds to flash on us an instantaneous view of our horrible surroundings, drowning in the midnight sea directly after, and leaving us to a worse mystery and dread. The wind blew from every point in the compass, and would have howled had there been anything to howl in, but trees there were none. Our way wound over a succession of bare, rocky ridges, like the perilous reefs of a sea suddenly drained dry. Some of these were two or three hundred feet above the general level, and as nearly perpendicular as they could be consistently with offering any possible foothold and passage to our horses. This part of the Overland road abundantly deserves its reputation of being the worst between the Missouri and Washoe. Like the boy in the song, I did not dare to sleep, and went, metaphorically, to walk the deck with the pilot. Bracing my feet against the dash-board, I saw that remarkable man at my side put his six-horse team (we were obliged to take an extra pair for this part of the route) over precipices where I should as soon have thought of driving over a wellcurb. Quintus Curtius at $50 a month! Even he acknowledged that he never drove this stage without expecting to break his neck. Frequently the valleys into which we dove were so narrow and abrupt (I say "valleys," though they were mere crevices of dislocation in perfectly bare rock) that our leaders were clawing their way up the slippery sandstone ledges,

while ourselves, our wheelers, and the middle team were rushing headlong with the weight of the wagon almost tumbling on them bodily. In one such place the descent was full sixty feet, with a 45° incline; and the road up the opposite wall of the chasm instead of lying in line with that we were descending, turned abruptly to one side nearly a full quadrant to avoid a precipice tenfold worse than that down which we were plunging. Talk of steeple-chases! A good horseman on his own trusty horse knows only the name of fear before any leap short of the eaves of a house; but cooped up with six in a box, he might well turn pale and be no coward. Save me henceforth from a steeple-chase in a wagon!

Soon after daylight broke we reached the Green River. The approach to it was through a picturesque cañon walled by perpendicular crags of red sandstone five or six hundred feet high. This formation was several miles in length, and abutted boldly upon the river, where its face was weathered into remarkable imitations of sculpture similar to that of the StoneCalvin Terrace, down whose giant staircase we had carefully crept to the last crossing of the Platte. At every turn some colossal profile of Indian, sphinx, helmeted warrior, or frowning Afrite projected from an outstanding vertical ledge. Often as I have had to refer to these strange mimicries of Nature's own carving, I cannot refrain from saying here that they always took us by surprise; and that for variety and number of profiles, no formation which we anywhere found marked by these strange freaks surpassed the present one.

A moment's glance at the Green River reveals the reason of its name, although its tinge tends rather