The whole page is taken up with the following notes:
Primary Light that which is received direct | Second Primary Light into 3 direct Reflected and refracted | Lomazzo gives this to emanation of the Deity radiation [Shanes: or adoration] of Glory | Third Primary Light to artificial light the fire in the | Broiling of St Laurence by Titian when the angle [i.e. angel] have | The Second Light
is that part of a body that evades the direct rays and | and is the stronger as the part which reflects the direct ray | is the broader and more so when it fall upon the <front> [‘back’ inserted above] | of such bodies that are lighted before by the direct ray
In the ray departing again to other bodies or through transparent | bodies as Glass and the more dense the broader but the less [?Dense]
Jerrold Ziff has identified these notes, continuing from one on colour opposite (folio 40 verso;
D07422), as free transcriptions from the 1598 English edition of Giovanni Paolo Lomazzo’s
Tracte Containing the Artes of Curious Paintinge Carvinge & Buildinge (see the sketchbook Introduction).
1The first paragraph comes from several brief chapters within ‘The Fourth Booke: Of Light’: chapter IIII, ‘Of the Division of Light’, page 142; the second from chapter VI, ‘Of the Second Primarie Light’, pages 144–5; and the last from chapter VII, ‘Of the Third Primary Light’, page 145.
The passage on reflected light is from the single-paragraph chapter X, ‘Of Reflected Light’, on page 149, and that on refracted light (as far as ‘Glass’) from chapter XI, ‘Of Refracted or Broken Light’, pages 149–50. The remainder appears to be taken from the beginning of chapter XII, ‘After What Sort All Bodies Receive Light More or Less’, on page 150: ‘because the elementes are naturally apt to bee charged and mixed with each other, wherefore ... it is most evident, that wheresoever they are found most pure, there the light which falleth upon them, is lesse apparent and more purified; and contrariwise brighter and of greater force, where they are thicker and grosser’.
Eric Shanes has discussed Turner’s understanding of Lomazzo’s Platonic, metaphysical explanation of the ‘Second Primary Light’ as the artist notes it, which concerns divine light emanating from angels and other heavenly sources; such sources perhaps nurtured the artists’s famous reported identification of the Sun with God towards the end of his life.
2 Shanes identifies Titian’s painting as the
Martyrdom of St Lawrence (Escorial, Spain).
Further passages of Turner’s extensive notes from Lomazzo appear later in the sketchbook, continuing on the verso of the present leaf (
D07424).
