If you write to me, pray in a couple of sentences tell me whether Herschell's thermometric "spectrum" (in the "Philos. Trans.") will lead to any revolution in the chemical philosophy. As far as "words" go, I have become a formidable chemist--having got by heart a prodigious quantity of terms, etc., to which I attach "some" ideas, very scanty in number, I assure you, and right meagre in their individual persons. That which must discourage me in it is, that I find all "power" of vital attributes to depend on modes of "arrangement", and that chemistry throws not even a distant rushlight glimmer upon this subject. The "reasoning", likewise, is always unsatisfactory to me. I am perpetually saying, probably there are many agents hitherto undiscovered. This cannot be reasoning: we must have a deep conviction that all the "terms" have been exhausted. This is saying no more than that (with Dr. Beddoes's leave) chemistry can never possess the same kind of certainty with the mathematics--in truth, it is saying nothing. I grow, however, exceedingly interested in the subject.
God love you, my dear friend! From Tobin's account, I fear that I must give up a very sweet vision--that of seeing you this summer. The summer after, my ghost perhaps may be a gas.
[Footnote 1: Letter CXVIII follows No. 107.]
Though we of the north must forego you, yet I shall rejoice when I receive a letter from you from Cornwall. I must believe that you have made some important discoveries in galvanism, and connected the facts with other more interesting ones, or I should be puzzled to conceive how that subject could furnish matter for more than one lecture. If I recollect aright, you have identified it with electricity, and that indeed is a wide field. I shall dismiss my 'British Critic' and take in 'Nicholson's Journal', and then I shall know something about you. I am sometimes apprehensive that my passion for science is scarcely true and genuine--it is but 'Davyism'! that is, I fear that I am more delighted at 'your' having discovered facts than at the facts having been discovered.
My health is better. I am indeed eager to believe that I am really beginning to recover, though I have had so many short recoveries followed by severe relapses, that I am at times almost afraid to hope. But cheerful thoughts come with genial sensations; and hope is itself no mean medicine.