appreciate its importance in the scale of territorial acquisitions, or which may serve to enlarge the sphere of national science. It is not to be expected that officers detached upon the duties can enter into the detail of such subjects in a manner which their importance would render desirable. But the most superficial observer may add something to the general stock; and to point their inquiries to specific objects, may be the means of eliciting facts, which in other hands may lead to important results. The most important tributary stream of the Upper Mississippi is the Saint Peter's. The commanding officer at the mouth of that river might be directed to form an expedition for exploring it. It is the opinion of Captain Douglass, and it is strongly fortified by my personal observation, and by the opinion of others, that Lieut. Talcott, of the Engineers, now at the Council Bluffs, would conduct a party upon this duty in a very satisfactory manner. He might ascend the St. Peter's to its source, and from thence cross over to the Red River, and descend the stream to the 49th parallel of latitude, with directions to take the necessary observations upon so important a point.[200] Thence up that branch of the Red River, interlocking with the nearest water of the Mississippi, and down this river to Leech Lake. From this lake, there is an easy communication to the River de Corbeau, which he could descend to the Mississippi, and thence to St. Peter's.[201] [200] This is the origin of Major Long's second expedition. [201] Explored by the preceding narrative in 1831-1833. The St. Croix and Chippewa Rivers, entering the Mississippi above and below the Falls of St. Anthony, might, in like manner, be explored by parties from the same post.[202] The former interlocks with the Mauvais and Brulé Rivers, but a descent into Lake Superior would not probably be considered expedient, so that the party would necessarily ascend and descend the same stream.[202] [202] Explored by the preceding narrative in 1831-1833. The Chippewa interlocks with the Montreal and Wisconsin Rivers, and consequently the same party could ascend the former and descend the latter stream. A party from Green Bay might explore Rocky River from its source to its mouth. A correct examination of Green Bay and of the Menomonie River might be made from the same post. The St. Joseph and Grand River, of this peninsula, could be examined by parties detached from Chicago. It is desirable, also, to explore the Grand Traverse Bay, about sixty miles south of Michilimackinac, on the east coast of Lake Michigan. These are all the points which require particular examination. Observations made in the manner I have suggested, and connected with those already taken by Captain Douglass, would furnish ample materials for a correct chart of the country.