Here we found it necessary to adjust a tube to the boilers of our steam-engine, in order to form a passage, through which the mud might be blown out: the method heretofore adopted, of taking off one end for the purpose of admitting a man to clean them, proving too tedious when it was found necessary to repeat the operation daily. The expedient of the tube succeeded to our entire satisfaction. Dr. Baldwin found here a plant, which he considered as forming a new genus, approaching astragalus; {63} also the new species of rose, pointed out by Mr. Bradbury, and by him called Rosa mutabilis. This last is a very beautiful species, rising sometimes to the height of eight or ten feet. The linden tree[090] attains great magnitude in the low grounds of the Missouri; its flowers were now fully expanded. In ascending from Bellefontain to Charboniere, where we came to an anchor, on the evening of the 24th, we were opposed by a very strong current, and much impeded by sand-bars. On the upper ends of these sand-bars are many large rafts of drift wood; these are also frequent along the right hand shore. In several places we observed portions of the bank in the act of falling or sliding into the river. By this operation, numerous trees, commonly cotton-woods and willows, are overturned into the water. The forests, on the low grounds immediately in the vicinity of the Missouri, are remarkably dense; but in many instances, the young willows and poplars (which are the first and almost the only trees that spring up on the lands left naked by the river) have not attained half their ordinary dimensions, before, by another change in the direction of the current, they are undermined, and precipitated down, to be borne away by the river. The growth of the cotton-tree is very rapid, that of the salix angustata, the most common of the willows found here, is more tardy, as it never attains to great size. The seeds of both these trees are produced in the greatest profusion, and ripened early in the summer, and being furnished by nature with an apparatus to ensure their wide dissemination, they have extended themselves and taken root in the fertile lands along all the ramifications of the Mississippi, prevailing almost to the exclusion of other trees. {64} Charboniere[091] is on the right bank of the Missouri. This name was given it by the boatmen and the earliest settlers, on account of several narrow beds of coal, which appear a few feet from the water's edge, at the base of a high cliff of soft sandstone. The smell of sulphur is very perceptible along the bank of the river, occasioned doubtless by the decomposition of pyrites, in the exposed parts of the coal beds. Some small masses of sulphate of lime also occur, and have probably derived their origin from the same source.