Joseph Mallord William Turner

Diagram 30 for Turner’s Lecture 3 as Professor of Perspective at the Royal Academy illustrates a perspective projection of a cube proposed by the French mathematician and designer or fortifications, Samuel Marolois (1572–1627). For his understanding of Marolois’s method, Turner relied on John Joshua Kirby’s Dr Brook Taylor’s Method of Perspective made Easy, both in Theory and in Practice (1768 ed., II, pl.XIX, fig.2);1 Turner owned a copy, which passed to him from his friend Henry Scott Trimmer, a descendant of Kirby (private collection). Turner also attributes the diagram to Jean-François Niceron (1613–1646), a geometrical theorist. According to Maurice Davies, Turner initially copied three diagrams from Niceron’s Thaumaturgus Opticus (1646, tab.3, fig. V; tab.6, fig.VIII; and tab.41, fig.LXXXVI) on a single sheet of paper.2 One of these diagrams (1646, tab.6, fig.VIII) ultimately informed his brief description in Lecture 3.3 Turner revised his description of Marolois’s and Niceron’s methods in a later version of the lecture.4

Technical notes:

Peter Bower states that the sheet is Double Elephant size Whatman paper made by William Balston, at Springfield Mill, Maidstone, Kent. The largest group within the perspective drawings, this batch of paper shows a ‘grid-like series of shadows that can be seen within the sheet in transmitted light. This appears to have been caused by a trial method of supporting the woven wire mould cover on the mould’. Because this is the only batch he has seen with such a feature, Bower believes that ‘it may have been tried on one pair of moulds and for some reason never tried again’. He also writes that it is ‘not the best Whatman paper by any means; the weight of this group is also very variable and the moulds have not been kept clean during use’.1

Verso:

Blank, save for an inscription by an unknown hand in pencil ‘76’ bottom left.