Davy returned to town in December, and after an interval wrote the following letter:
TO THOMAS POOLE, ESQ.
Park Street, Grosvenor Square, Dec. 27, 1827.
MY VERY DEAR FRIEND,
I know no reason why I have not written to you. It has been my intention every day, and I have been every day prevented by the sense of want of power, which is so painful a symptom of my malady.
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.