June 3, 1805 entry by Meriwether Lewis

This morning early we passed over and formed a camp on the point formed by the junction of the two large rivers.    here in the course of the day I continued my observations as are above stated. An interesting question was now to be determined; which of these rivers was the Missouri, or that river which the Minnetares call Amahte Arz zha or Missouri, and which they had discribed to us as approaching very near to the Columbia river.    to mistake the stream at this period of the season, two months of the traveling season having now elapsed, and to ascend such stream to the rocky Mountain or perhaps much further before we could inform ourselves whether it did approach the Columbia or not, and then be obliged to return and take the other stream would not only loose us the whole of this season but would probably so dishearten the party that it might defeat the expedition altogether.