MY DEAR MR. SULLY:— I received from your truly friendly letter of the 7th. of November the long wished for intelligence that you and your family were well. I am not much astonished that in Philadelphia, remarks such as you allude to, should have been made respecting some papers on the habits of objects of Natural History, read by me to different institutions in this country, but I am grieved at it. The greatest portion of my life has been devotedly spent in the _active_ investigation of Nature, her beauties & her objects in granting to different individuals, classes, or species, such privileges as best suit their form, situation, or habits. This arduous task I have followed with unremitting diligence, and with a degree of industry that has caused to my family and to myself more troubles than any person in Philadelphia can be aware of. For more than 20 years I have been in _the regular habit_ of writing down every day all the incidents of which I have been an _eye-witness_, on the spot, & without confiding to my memory, as many travellers have done and still do. You have read some portion of this journal, and have also been an eye-witness of many of the occurrences, and to this I now owe the gratification of possessing your esteem, but, My dear Mr. Sully, you are not the only evidence. Mr. Joseph Mason, who is now, I believe, an artist in your city, accompanied me on a hunting excursion, beginning at Cincinati, and ending in the State of Louisiana, which lasted 18 months. He drew with me; he was my _daily companion_, and we both rolled ourselves together on bufaloe robes at night. James Cummings, Esq., past captain, the author of a treatise on the navigation of the rivers Ohio and Mississippi, was one of the party, and he saw me write in my Journal, and read it frequently. Every member of my family has seen the whole of those Diaries and could readily assert the truth of the whole of their contents, to many of which they were party, present and acting. The papers alluded to in your estimable letter, are merely copies from those journals; they were transcribed in Edinburgh, and the style corrected by patrons, who saw the originals, nearly worn out by time and the casual dampness, which journals like mine must often be exposed to. I read these papers to the different societies, of which I have the honor to be a member, and read them with a sensation of pleasure that nothing but a full persuasion of their truth could bestow.