TO JONATHAN WILLIAMS AND C. W. PEALE, JUDGES OF ELECTION FOR THE A. P. SOCIETY. WASHINGTON, January 12, 1807. GENTLEMEN,--I am again to return the tribute of my thanks for the continued proofs of favor from the American Philosophical Society; and I ever do it with sincere gratitude, sensible it is the effect of their good will, and not of any services I have it in my power to render them. I pray you to convey to them these expressions of my dutiful acknowledgments, and to accept yourselves thanks for the favorable terms in which your letter of the 2d instant announces the suffrage of the Society. I am happy at the same time to greet them on the safe return of a valuable member of our fraternity, from a journey of uncommon length and peril. He will ere long be with them, and present them with the additions he brings to our knowledge of the geography and natural history of our country, from the Mississippi to the Pacific. Tendering them my humble respects, permit me to add for yourselves my friendly salutations, and assurances of high consideration. TO MR. GALLATIN. January 12, 1807. I return you the letter of Mr. Gelston respecting the Brutus. From what I learn, she cannot be destined for the Mississippi, because she draws too much water to enter it. However, considering the difficulty Congress finds in enlarging the limits of our preventive powers, I think we should be cautious how we step across those limits ourselves. She is probably bound to St. Domingo. Could not Congress, while continuing that law, amend it so as to prevent the abuse actually practised. Affectionate salutations. TO JOHN DICKINSON. WASHINGTON, January 13, 1807.