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Between the two diagrams, with reference to the upper (of a two-storey building), Turner notes: ‘it is [?evident] that by the circle that the upper window must smaller | by the circle, but it does not say how the difference is to be found | Salomon de Cavs 1612’. At the foot of the page is the concluding phrase of the long inscription opposite (folio 2 verso; D07358), relating the origins of ancient art.
Maurice Davies has identified the notes and diagrams on folios 3 recto to 4 verso (this page and D07360–D07362) as taken from Salomon de Caus, La Perspective avec la raison des ombres et miroirs, London 1612 (see also folio 54 verso; D07450), in the present case from the unpaginated folio 5 recto. The same passages are translated from the French in Turner’s perspective lecture manuscripts, though apparently not in his hand.1
Davies 1994, pp.98, 287, 298 note 23; Davies notes the translations as in Turner, ‘Royal Academy Lectures’, circa 1807–38, Department of Western Manuscripts, British Library, London, ADD MS 46151 BB folios 62 recto, verso.