This was possibly and not improbably, the last letter this great, this learned, indefatigable, most excellent and extraordinary man ever wrote, for on the 4th of February, 1804, he was released from his labors and sufferings. Peace, rest, joy and glory to his soul! For I believe he had one, and one of the greatest. I regret, oh how I lament that he did not live to publish this work! It must exist in manuscript. Cooper must know something of it. Can you learn from him where it is, and get it printed? I hope you will still perform your promise to Doctor Rush. If Priestley had lived, I should certainly have corresponded with him. His friend Cooper, who, unfortunately for him and me and you, had as fatal an influence over him as Hamilton had over Washington, and whose rash hot head led Priestley into all his misfortunes and most of his errors in conduct, could not have prevented explanations between Priestley and me. I should propose to him a thousand, a million questions. And no man was more capable or better disposed to answer them candidly than Dr. Priestley. Scarcely anything that has happened to me in my curious life, has made a deeper impression upon me than that such a learned, ingenious, scientific and talented madcap as Cooper, could have influence enough to make Priestley my enemy. I will not yet communicate to you more than a specimen of the questions I would have asked Priestley. One is; Learned and scientific, Sir!--You have written largely about matter and spirit, and have concluded there is no human soul. Will you please to inform me what matter is? and what spirit is? Unless we know the meaning of words, we cannot reason in or about words. I shall never send you all my questions that I would put to Priestley, because they are innumerable; but I may hereafter send you two or three. I am, in perfect charity, your old friend. JOHN ADAMS TO THOMAS JEFFERSON. QUINCY, August 9, 1813. I believe I told you in my last that I had given you all in Linsey's memorial that interested you, but I was mistaken. In Priestley's letter to Linsey, December 19th, 1803, I find this paragraph: "With the work I am now composing, I go on much faster and better than I expected, so that in two or three months, if my health continues as it now is, I hope to have it ready for the press, though I shall hardly proceed to print it till we have dispatched the notes. "It is upon the same plan with that of Socrates and Jesus compared, considering all the more distinguished of the Grecian sects of philosophy, till the establishment of Christianity in the Roman empire. If you liked that pamphlet, I flatter myself you will like this. "I hope it is calculated to show, in a peculiarly striking light, the great advantage of revelation, and that it will make an impression on candid unbelievers if they will read.