I offer you many thanks for the 1st. vol: of Memoirs published by your Agricultural Board.1 It contains a very valuable mass of instruction both Theoretical & Practical. If it had not the benefit of the materials expected from the subordinate Societies, it must be of great use in stimulating and guiding their reports which may succeed it.

I am very glad to find that it fell within the scope of your disquisitions, to unfold the present Chemical doctrine with regard to the elements of matter; particularly the organized parts of it. It will answer well the purpose of counteracting any general imputations from unfriendly quarters; should pretexts for such be taken from the defective views of the subject, in the paper, which I see has been honored with a place in your Volume.

On the supposition, as authorized by facts, that a combination of two elements may produce a third substance different from both; that a combination of a greater number may proportionally diversify such new results; and that a change even in the proportions of the same elements combined may have like effects; a field seems to be opened for a possible multiplication, from a few elements, of the forms and qualities of matter such as the face of our globe now presents. It does not necessarily follow however from this possibility, that all the varieties now beheld in the productions of nature, could be converted into a single or few classes of them. It is more than probable that there are laws, in the economy of nature, which would not admit so entire a metamorphosis of her original System; that there may be certain relations between different classes of her productions, which require for their preservation and increase, the existence & influence of each other. And it seems certain that such a revolution would have the consequence, not easily to be admitted, of rendering a portion of elementary matter, supernumerary & useless for the laboratory of nature.

Whatever be the number of distinct elements or gases, as these must be inconvertible one into another, the existing mass of each element must be of fixt amount, and bear of course a fixt proportion each to the others, in the existing order of things. Taking then any particular class or classes of plants, (those for example of human use) which happen not to comprize every distinct element, or tho’ comprizing every element, yet in proportions not2 corresponding with the proportions now existing in the whole vegitable creation, a destruction of every other class of plants would necessarily leave unemployed all the elements not required for the new modelled Systems.

Perceiving how far I have wandered from my proper object, I hasten a return to it, by repeating my acknowledgments for your valuable Book, with assurances of my esteem and cordial respects.