Your unacknoleged letters of July 9. Oct. 8. & Nov. 10. prove I have been long in arrears with you. you have probably known before this that the Colo. Freeman thought of for the Red river expedition was a different person from the military officer. the one proposed for this expedition is now here, and will be the bearer of this letter. he is well qualified for the geographical part of the business and we hope we have procured a good botanist to accompany him. the Secretary at War will give orders that the officer who under former orders keeps up a patrole in the neighborhood of Bayou Pierre, attends to the unmolested passage of Colo. Freeman’s party clear of danger from that settlement. I inclose you Doctr. Barton’s account of the Botanical specimens you sent me from the Washita. as it was material to have the map of the Washita ready drawn, engraved & struck off for Congress, we had put your notes into the hands of mr King, a skilful person, who had done the business, and I now send you one of the engraved charts. yours will be preserved to enter into the General Map of the US. which on the return of our exploring parties we shall endeavor to have composed & published. we have capt Lewis’s notes of the Missouri to his wintering place at Fort Mandan, and a map of the whole country watered by the Missouri & Columbia composed by himself last winter on very extensive information from Indians & traders, in which he expresses a good deal of confidence. you will have percieved that my suggestion of a method of finding the longitude at land without a time piece was that of a theorist only, not a practical astronomer. it was founded too in the use of the Equatorial the only instrument with which I have any familiarity. I never used the Quadrant at all, and had thought of importing three or four Equatorials for the use of these parties: they get over all difficulty in finding a meridian. the suggestion however of my imperfect method has had the good effect of producing those less so. your own, founded in practical skill will doubtless answer it’s end. I inclose you a method deemed by mr Joshua Moore of this place. Colo. Freeman will communicate to you one of mr Patterson’s. he will have an opportunity of deciding from experience which is preferable of the whole. we have no certain information of Capt. Lewis since he left Fort Mandan. but we have through Indians an account of his having entered on the passage over the highlands dividing the Missouri from the waters of the Pacific. Accept my friendly salutations & assurances of great esteem & respect.