Sends JH samples of his calotypes. Off to Germany on a photographic expedition.

Carl Steinheil has proposed making telescope mirrors by plating silver on glass. Is writing to JH to tell him that somewhat earlier he had included this process in one of his patents.

JH's account of a comet reminds WT of a strange sighting many years ago. Comments further on improvements in photography, both those made and those needed.

Describes observing of comet that evening.

Suggests 'amphitype' as name for JH's process whereby same picture can go from negative to positive. Further comments on comet sighting, and on some improvements to Daguerreotype.

Comments on JH's positive calotype. Suggests comet may be return of (J.-D.) Cassini's comet of 1668. Gives theorem for finding parabolic orbit of comet if two observations are made in the ecliptic.

Comments and questions about a 'cone of the second order' in mathematics.

Some comments and questions on mathematics.

Comments on astronomical symbols, and position of camera when photographing buildings.

Has performed experiments measuring the deviation of spectra through an obliquely placed diffraction grating. Believes they strongly support the wave theory of light.

Refers to process which produces pictures that are negative or positive depending upon the light. Hopes to use it to photograph lunar landscape. Wants to call it 'amphitype' if JH agrees.

Describes observing solar eclipse at Marienburg in eastern Prussia. Gives advice about whom to see for photography training [see 1851-7-27].

Questions and comments regarding improvements in microscopy.

Comments on several experiments with spectra passing through glass films.

Congratulates JH on appointment to Mastership of Mint. Hopes JH, as member of Cambridge University Commission, will introduce needed reforms.

Grateful for receipt of JH's Cape Results. Sending photographs by several artists to show that 'knowledge of the art is spreading.'

Continues account of the vegetation of Corfu. Has only explored the environs of the city, but told of "extraordinary" plants in the remoter parts of the island by director of the botanic gardens, including: 'Echium giganteum'; 'Othonna pectinata' and another 'Othonna'; 'Osteospermum piliferum' and 'Osteospermum moniliferum'; 'Nolana prostrata'; 'Chrysocoma coma-aurea'; and a yellow climber, either 'Dolichos' or 'Crotalaria'.

His discoveries: characters of two new 'Euphorbia' resembling 'Euphorbia peplus' and 'Euphorbia exigua'; and found a large white-flowered 'Lithospermum'; 'Stachys spinulosa ?' with white flowers; 'Veronica syriaca'; 'Phleum felinum ?'; 'Convolvulus tenissimus'; 'Crambe corvini' (not in "Prodromus [Florae Graecae]"); 'Lotus tetragonolobus'; 'Lathyrus setifolius'; 'Bunias erucago'; 'Ornithopus scorpioides'; 'Andropogon distachyon'; 'Aristolochia rotunda'; 'Allium subhirsutum'; 'Urospermum picroides'; 'Hesperis verna'; 'Rhagadiolus stellatus'; 'Polypodium leptophyllum ?'; 'Anthyllis tetraphylla'; 'Euphorbia amygdaloides', abundant (not in "Prodromus [Florae Graecae]"); a 'Geranium' with large flesh-coloured flowers; 'Vicca bithynica'; 'Coronilla securidaca'; etc. About to visit island of Santa Maura, the ancient Leucadia.

Sending a copy of [Antonio] Bertoloni's "Amoenitates Italicae". Compared the collection of plants he gathered from Corfu and other islands with Bertoloni's herbarium, the best in Italy, but still has doubts which he can only clear up by consulting [John] Sibthorp's original specimens. [David] Don [(1799-1841), botanist] wants him to communicate his Ionian flora observations to Linnean Society but does not think them interesting enough. The Ionian 'Umbelliferae' are "numerous & extraordinary" and seem little known, could not even apply genera to many of them, although a copy of "Flora Graeca" in the Grand Duke's Library in Florence was helpful.

Delaying his Ionian flora paper for Linnean Society until next spring as expects to go to Paris soon. Frustrated by botanical travellers who do not mention in their "Floras" what plants chiefly abound in a district; it is not the few rare flowers that characterise a region's vegetation. Lists the plants that are strikingly abundant on Corfu: 'Phlomis fruticosa'; 'Asphodelus ramosus'; 'Ornithogalum exscapum' Tenore, thinks it the 'Ornithogalum nanum' Sibthorp; 'Geranium umbrosum' Tenore; 'Scilla maritima'; 'Lycopsis variegata'; 'Scrophularia peregrina'; 'Phalaris [ariculata]'. On island of Zante: 'Salvia triloba'; 'Hedysarum humile'; 'Hedysarum caput-galli'; 'Chrysanthemum coronarium'; 'Cynara humilis'?; 'Anthericum graecum'; 'Poterium spinosum'; and 'Cistus salicifolius'.

Has discovered two varieties that may be new species: a 'Lithospermum orientale' which on Corfu always has white flowers, and 'Trifolium stellatum', which elsewhere has pink flowers but on Corfu bright yellow. Found specimen of 'Cytinus hypocistis', it resembles a wax model more than a living plant. An 'Umbelliferae' on Zante with a triangular stem, [Antonio] Bertoloni calls it 'Laserpitium triquetrum'. 'Staehelina chamaepeuce' grows on cliffs on Zante. Did not see 'Veronica chamaedrys' on Corfu but a 'Veronica' very like it. Also found two "very singular" 'Euphorbia', one described by [Felix de Avellar] Brotero [(1744-1828)] as 'Euphorbia [pterococca]' and 'Euphorbia sexangularis' by Sprengel, the other would have been new but it was discovered by [Giovanni] Gussone [(1787-1866)] in Sicily last year.

Offers to obtain any or all of the Hungarian plants described by [Franz Adam von] Waldstein and [Paul] Kitaibel in ["Descriptiones et icones plantarum rariorum Hungariae"] from a Munich botanist, in exchange for British specimens.

[Note, possibly in Smith's hand] "of Laycock Abbey, Nephew of Ld Lansdown".