of the operation of the Mississippi, at this time, upon its valley, is to fill up rather than to excavate; but it may be doubted whether this is equally, or even to any degree, the case with the Missouri. The aggregate mass of alluvion within the valley of the Missouri is, undoubtedly, moving downwards, with considerable rapidity; for the quantity of earthy matter carried into the Mississippi is, at all times, very great. In their descent the alluvial substances are alternately deposited and swept away, as by the variations in the direction of the current any particular point is, from time to time, either exposed to, or sheltered from, the action of the stream. About eighty-seven miles above Cow Island is the mouth of the Nodowa, a river of some importance, being about seventy yards wide, and navigable to some distance. It is not usually seen in passing, being {107} concealed by the island called the Great Nodowa, which is about five miles long, and covered with heavy forests. The lands on the Nodowa are of an excellent quality.[149] On the 1st of September, we were under the necessity of remaining encamped near the mouth of Wolf river,[150] that some repairs might be made to the steam engine. Here we sent out some persons to hunt, who after a short time returned, having taken a deer, a turkey, and three swarms of bees, which afforded us about half a barrel of honey. On the trees which margin the river, we frequently observed a fine species of squirrel, which possesses all the graceful activity of the common gray squirrel, as it leaps from bough to bough.[151] After our machinery was adjusted, we resumed our ascent, and had proceeded a short distance, when we were hailed from shore by Mr. Dougherty, who had accompanied Mr. Say's party across the country. We were not a little surprised at this unexpected meeting, and were apprehensive some disaster had befallen the detachment. Mr. Dougherty being received on board, informed us that Mr. Peale, Mr. Swift, Mr. Seymour, Chaboneau the Indian interpreter,[152] and one of the soldiers, were at a little distance in the rear, having accompanied him across the country, from Cow Island, where they had arrived five days after our departure. Mr. Say and Mr. Jessup had been left sick at Cow Island. We encamped immediately, to give those who were near an opportunity of joining us. It will now be necessary to return to the time of Mr. Say's departure from Fort Osage, and briefly to trace the progress of his detachment to the place where a rencontre with a war-party of Pawnees frustrated their design, and made it necessary for them to rejoin the steam-boat.