The whole page is taken up with the following notes, including a diagram towards the top:
Suppose over an iregular horizon or hill | on which a building [...] but one more | elevated than the rest
Here there is a diagram of a building against a wooded or cloudy horizon with dotted arcs in the sky above, numbered ‘2’ above the building and ‘1’ to its right. The notes continue:
immediatly opposite to which will suppose | a flat surface upon the upper part the | first appearance of the sun will show it <[?power]> | approach by color and a small increase of light | but which imperceptibly loses itself downwards | without any visible shadow of an object upon | that surface positivly defined any more | the indefinite shadow that common daylight | makes and a pole at [blank] yards would only | be marked where the ½ [overwriting ‘small’] part of the pole strikes | its positive power while the shadow of the | pole would be wholy blended in shade causd | on the same flat surface as yet not illumined
This passage follows on from the verso of this leaf (
D07503), and continues on the opposite page, folio 86 verso (
D07501) – where the diagram appears to be referred to again. 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).
3Gage has also mentioned this particular passage ‘on the development of a sunrise’, running back to folio 84 verso (
D07497), in the context of Turner’s keen observations of light, weather and water, more commonly expressed visually in his sketches.
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