I continue much as I was. My physicians augur well, and I have some repose in the hopes connected with the indefinite future. In the last twelve-month, which I hope is a large portion, on the whole, of my purgatory expiation for crimes of commission or omission, the most cheerful, or rather the least miserable, days that I spent, were a good deal owing to your kindness, which I shall never forget. I would, if it were possible, make my letter something more than a mere bulletin of health, or the expression of the feelings of a sick man; but I can communicate no news. The papers will tell you more than is true; and our politicians seem ignorant of what they are to do at home, much more abroad. * * * * * I have got for you a copy of my lectures on the Chemistry of Agriculture, which I shall send to you by the first opportunity. God bless you, my dear Poole. I am always your sincere, Grateful, and affectionate friend, H. DAVY. In the letter which follows, Davy dwells upon a subject in Natural History, which appears to have greatly occupied his thoughts, and to have continued a predominant subject of his contemplation, even to the latest day of his life. TO THOMAS POOLE, ESQ. Park Street, January 1, 1828. MY DEAR FRIEND, I write to you immediately, because that part of your letter which relates to Mr. Baker's pursuits interests me very much: but before I begin on this subject, I will give you a short bulletin of the state of my health. I go on much as I did at Stowey, and my physicians have made no alterations in the plan of treatment: I am not worse, and they tell me I shall be better. Now for Mr. Baker--I am very glad that he is occupied with those enquiries. I am particularly anxious for information on the generation of eels; it is an unsolved problem since the time of Aristotle. I am sure that all eels come from the sea, where they are bred; but there may be one or two species or varieties of them. What Mr. Baker says about the difference between the common eel and the conger is well worthy of attention; but I have known changes more extraordinary than the obliteration, or destruction, of a small tubular member occasioned by difference of habits. Were the salt-water eels and the fresh-water eels which he examined of the same size? Many individuals of various sizes should be examined to establish the fact of their specific difference. This would be the season for examining the genital organs of eels, for they breed in winter; and were I a little better, I should go to the sea for the purpose of making enquiries on the subject.