They here met a party from the Hudson Bay Company, led by a Mr. McCoy. Carson and five of his companions accepted the offer he made them, and went with him to the Humboldt river, trapping with little success from its source to the desert where it loses itself, and where the termini of several other large rivers are all within a day's ride, according to the statement of residents at this point. Capt. McCoy said to Carson, as he and two of the company started off upon the desert, "Do not be gone longer than to-morrow night, and if you strike a stream where there is beaver--there must be water between here and those snow mountains--we will trap a few days longer." On they rode over the artemisia plain till the lake was out of view from an eminence which Carson climbed; then struck a tract of country entirely destitute of every sign of animal or vegetable life, with surface as smooth as the floor for miles in extent, then broken by a ridge a few feet high, like the rim to a lake, whose bottom they had passed, to plunge immediately upon another like it, with perhaps a white and glistening crystalization spread thinly over it. Carson knew he must be upon the celebrated Mud Lakes of which he had heard, and of which he had seen miniature specimens further east. Over these lake bottoms of earth, that broken, seemed like mingled sand and ashes, but which bore the tread of their horses, and over which they seemed to fly rather than to step, so fragrant and exhilarating was the atmosphere, they traveled thirty miles, then struck the artemisia plains again, only there was less of even this worthless production for the next ten miles than he had seen before for long a distance. Through a heavy sand, the weary horses plod, for they had come forty or fifty miles beneath a burning sun without food and without water. On they ride, for rest and refreshment to themselves was not to be thought of till they have it for the animals. The river is gained! a broad, deep current of water, muddy like that of the Platte, supplies the moisture to the trees, whose tops ascend only a few feet above the desert level, and whose trunks rise from green meadows but little above the surface of the water. The bottom lands are narrow, and the abrupt bank descends to the water perpendicularly twenty feet or more, seemingly of clayey earth, so soft, the water constantly wore upon it, and evidently the river channel was settling, as the years advanced. There were no signs of beaver, and, from the nature of the banks, there could be none, unless high up on the stream. CHAPTER XII.