No summary available.

Found 'Buxbaumia aphylla' in Peebleshire this autumn, within two miles of the place he gathered it last year; observations. Found a sufficient number of specimens to include it in his "Hortus Cryptogamicus Edinensis", which is just about to be published. The other species, 'Buxbaumia foliosa', is not rare in this area. Encloses specimen of the 'Buxbaumia aphylla'.

Received Smith's letter of 24 [November 1819]; pleased to find he has discovered a new natural history fact, even if "so little interest as the duration of a moss". Offers to send specimen of 'Vaucharia humata' in spring, which he published as a British specimen in June last.

Discusses recent developments in classification and nomenclature with reference to [Alexander von] Humboldt, Persoon, and De Beauvois. Discusses genus 'Buxbaumia' and discovery by [Robert] Brown regarding leaves on the bulb, with reference to [William Jackson] Hooker, Sir Joseph Banks, and Micheli. Has been studying the Acharian method for three years but unsatisfied regarding synonyms of compound terms, discussion of this. Discussion regarding how to unify the fungi systems of [James] Sowerby and [Christiaan Hendrik] Persoon. Encloses "trivial collection of mosses". Edinburgh has been "plunged" into a "botanical lethargy" for some time. Offers to acquire any Scottish plants for Smith.

[Spec 26 written in pencil at head of verso of first folio]

Is willing to be a witness to some battery experiments by J. P. Gassiot, but JH is busy, mostly with house hunting, and so may not be available.

Agrees to provide Josiah Quincy with extracts from letters by James Grahame. Highlights of Grahame's life.

Explains in detail his photographic method for producing landscapes on paper.

Describes a method developed by [J. J.] Heilmann of 'taking from glass negatives positive impressions of different dimensions.' Praises JH's suggestion that public records be preserved on microscopic negatives.