To read Clark's letters and papers is to discover that his education in the politer branches of learning was as primitive as the surroundings of his home. It is plain that the training which prepared him for manhood was got mostly outside the schoolroom. Like Lewis, he chose a military career. When he was but eighteen years of age, he was appointed ensign in the regular army; and two years later he was made captain of militia in the town of Clarksville, "in the Territory of the United States North West of the Ohio River." In 1791 he was commissioned as a lieutenant of infantry, under Wayne, and served afterward as adjutant and quartermaster. Ill health led him to resign his commission in the army in 1796. A few months before his resignation he first became acquainted with Meriwether Lewis, who, as an ensign, was put under his command. Then began one of those generous and enduring friendships that are all too rare amongst men. It is not known just what their private relations were in the mean time; but in 1803, upon Lewis's earnest solicitation, Captain Clark consented to quit his retirement upon his Kentucky farm and join in that work which was destined to be but the beginning of his real usefulness. He comes to us out of the dark. We must forego intimate knowledge of his growth, being content with finding him full-grown and ready. No doubt his service in the army, where he was associated with men of ability, had helped him to master many details of engineering craft, which he was to use in his later service. But this was at most incidental; his strength, his power to serve, was native, not acquired. That they might share alike in all particulars of rank and responsibility in the expedition, it was understood that Lewis would endeavor to procure for Clark a captain's commission. Clark wrote to Nicholas Biddle (the editor of the journals) in 1811:-- "On these conditions I agreed to undertake the expedition made my arrangements, and set out, and proceeded on with Capt. Lewis to the mouth of the Missouri where we remained the winter 1803 made every necessary arrangement to set out early in spring 1804 everything arranged I waited with some anxiety for the commission which I had reason to expect (Capt. of Indioneers [Engineers]) a few days before I set out I received a Commission of 2d Lieutenant of Artillerist, my feelings on this occasion was as might be expected. I wished the expedition suckcess, and from the assurence of Capt. Lewis that in every respect my situation command &c. &c. should be equal to his; viewing the Commission as mearly calculated to authorise punishment to the soldiers if necessary, I proceeded. No difficulty took place on our rout relative to this point...."