directions, and so abundantly in some places that they seemed to have filled whole valleys. In several places the openings of ancient craters were still to be distinguished. The argillaceous and volcanic strata of the mountains are generally horizontal; but in several places they hang perpendicularly, or else they are curved or wavy; often one might take them for artificial works.
On the 22d of July the camp came to Henry's lake, one of the principal sources of the Columbia; it is about ten miles in circumference. We climbed on horseback the mountain that parts the waters of two great rivers; the Missouri, which is properly speaking the main branch of the Mississippi and flows with it into the Gulf of Mexico, and the Columbia, which bears the tribute of its waters to the Pacific Ocean. From the elevated spot at which I was I could easily distinguish Mosquito lake," source of one of the main branches of the north fork of the Missouri, called Jefferson River.
The two lakes are scarce eight miles apart. I started for the summit of a high mountain, for a better examination of the fountains that give birth to these two great rivers; I saw them falling in cascades from an immense height, hurling themselves with uproar from rock to rock; even at their source they formed already two mighty torrents, scarcely more than a hundred paces apart. I was bound to get to the top. After six wearisome hours, I found myself exhausted; I think I must have climbed more than 5,ooo feet; I had passed snow drifts more than twenty feet deep, and still the mountain top was at a great height above me. I therefore saw myself compelled to give up my plan, and I found a place to sit down. The fathers of the Company who are in the missionary service on the banks of the Mississippi and its tributaries, from Council Bluffs to the Gulf of Mexico, came to my mind. I wept with joy
11 Le lac des Maringouins ; Red Rock lake. This lake is the most distant from the sea, by river channel, of any lake upon the globe. It is the ultimate source of the Missouri.