Read it through once

I have never given up, until now. But now I have given up. I am going to die. I made up my mind last night that it must be, and very soon, too. You say you are going to revisit your river, by-and-bye, when you find opportunity. Very well; that, together with a certain strange experience which fell to my lot last night, determines me to tell you my history--for you will see Napoleon, Arkansas; and for my sake you will stop there, and do a certain thing for me--a thing which you will willingly undertake after you shall have heard my narrative.