The top two thirds of the page are taken up with the following notes:
Hence 3 diffculties or irrconciable appear | First the approach of the sun upon the | Horizon. the rays appear to diverge yet remote | Buildings are lost in the brilliance and seem | to cast no shadow when risen and also objects | near to the eye and themselves that receive the | light of the whole orb give their proportions nearly | parallel. The rays of the setting or rising sun | counteracts the notion of parallel | while shadows of near objects suport it – | distant objects are lost <as convergen> rays | [‘crossed’ inserted above] and if I were cald upon for my opinion shoud | rather think that hypothesis would come – | near to a reconciation [sic] of the differences than | any other which is enforcd by the ray of the | luminary when it approach the horizon
Below are three diagrams of disks with rays emanating at many angles, all crossed out with continuous, near-parallel zigzag strokes; compare the diagram on folio 89 recto (D07506).
This passage follows on from folio 86 verso (D07501) and continues on folio 84 verso (D07497). It is part of a sequence beginning on folio 91 verso (D07511), and running back to folio 82 verso (D07493). John Gage has discussed these provisional notes (not developed in the perspective lectures) as an example of Turner’s close observation of natural phenomena,1 in this case the question of sunlight travelling in parallel lines or otherwise, responding to a chapter of The Art of Painting by Gérard de Lairesse (1640–1711), in the English translation by John Frederick Frisch (London 1738 and later editions).2 See under D07511 for a discussion of Lairesse’s text. Maurice Davies has registered Turner’s notes as ‘on light and shadow’, as part of a longer sequence running back to folio 72 verso (D07473).3