Most of the page is taken up with the following notes:
Suppose upon the principles of Ger L | we conclude that the sun is near upon | the Horizon and the wall in [?black] – | 3000 yards or across a river that the | last wall would be the parrallel | ray be cut nearly in Half by the line | the suns altitude make but [...] | we should find it so modifyd by the distance | that it could not be calld a positive | shadow while a branch a tree or | blade of grass would be transferred on | the [?’upper part’ inserted above] second wall of a tree [?’grew a few’ inserted above] yards | from it
Below is a sketch or diagram of houses among trees, apparently with the outline of the cast shadow of a roofline with chimneys half way up the end wall of the house on the left.
This passage follows on from folio 84 verso (D07497) and continues on folio 82 verso (D07493), the last page of a sequence beginning on folio 91 verso (D07511). 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