Concerning the variety, importance, and extent of its latent mineral resources, I think little doubt can remain. Every fact which has been noticed tends to strengthen the belief that future observations will indicate extensive mines upon its shores, and render it an attractive field of mineralogical discovery. In the event of mining operations, the facilities of a ready transportation of the crude ores to the Sault de Ste. Marie, will point out that place as uniting, with a commanding geographical position, superior advantages for the reduction of the ores, and the general facilities of commerce. At this place, a fall of twenty-two feet, in the river, in the distance of half a mile, creates sufficient power to drive hydraulic works to any extent; while the surrounding country is such as to admit of an agricultural settlement. I accompany this report with a geological sketch of a vertical section of the left bank of the Mississippi at St. Peter's, embracing a formation of native copper. This formation was first noticed by the officers of the garrison, who directed the quarrying of stone at this spot. The masses of copper found are small, none exceeding a pound in weight. I have the honor to be, sir, With great respect, Your ob't servant, HENRY R. SCHOOLCRAFT. VII. _Observations on the Geology and Mineralogy of the Region embracing the Sources of the Mississippi River, and the Great Lake Basins, during the Expedition of 1820. Illustrated with Geological Profiles, and Numerous Diagrams and Views of Scenery._ By HENRY R. SCHOOLCRAFT, U. S. Geol. and Minera. Exp. To the Hon. JOHN C. CALHOUN, _Secretary of War_. WASHINGTON, April 2, 1822. SIR: I have the honor, herewith, to submit the general report of my observations on the geology and mineralogy of the region visited by the recent expedition to the sources of the Mississippi River. I transmitted to the Department on the 6th of November, 1820, a report on the existence of Copper Mines in the Basin of Lake Superior, together with specimens of the native metal, which were politely taken charge of at Albany by General Stephen Van Rensselaer, M. C. Will it be consistent with the views of the Department to print these reports? I have the honor to be, sir, Very respectfully, Your obedient servant, HENRY R. SCHOOLCRAFT. REPLY. WAR DEPARTMENT, April 6, 1822. SIR: I have received your interesting report on the geology and mineralogy of that section of the western country embraced by the late expedition of Gov. Cass; and, although I have not had it in my power, as yet, to peruse it with attention, I will see you, at any time you please, on the subject of your letter respecting it. I am, sir, Respectfully, Your obedient servant, J. C. CALHOUN. Mr. HENRY R. SCHOOLCRAFT. ALBANY, March, 1822.