Joseph Mallord William Turner

This lecture diagram on white wove Whatman paper shows four identical columns topped by an entablature, with the blocks of the wall behind the colonnade ruled in graphite pencil between one pair of columns, and strengthened with grey/black paint in the spaces behind three more columns. All the vertical lines are also strengthened with black paint, and some of the shadows in the bases are emphasised with browner wash to depict shadows. It is a copy of a lost original, as is Tracing of Guiding Lines (Tate D17132; Turner Bequest CXCV 161). There is no depiction of major shadows or their effects, in contrast to Tate D17142 (Turner Bequest CXCV 171) which illustrates this in several ways.

The present work was made by a copying process which Turner used to generate a limited number of copies from other lecture diagrams. It is rare that all or even most stages of the process survive, and there is no complete set in the Turner Bequest, since these materials were presumably transported to and used for a number of lectures over the years. He needed several copies so that he could if he chose illustrate the drawing of a single element such as a column alone, then later with perspectival lines going to a single point, or built up to a colonnade of identical columns, or used to illustrate the way to make a smooth column look three-dimensional by shading. He could also use such a colonnade to form part of the elevation of a building, as in this example, with the vertical fluting of one column illustrated, to show its portrayal as a three-dimensional form.

The process seems to have involved placing a blank sheet on a table, overlaying double-sided copying paper, followed by another blank sheet, another sheet of double-sided copying paper, and the image to be copied. In this case it would have been either a single column or a four-column colonnade, drawn in outline. Then he pressed down hard on each ruled line of the top copy with a sharp tool run against a ruler, and unpacked the paper stack to reveal one good and one pale copy, with little smudging on the ‘good’ sides. If necessary, he strengthened straight lines in the copies, which would both be identical and not reversed, and then he hand-applied the curved elements freehand as necessary, and/or painted the lines to make them bold enough to demonstrate to a large audience in a room lit artificially. Sets of copies identified thus far include: Building in Perspective (Tate D17051; CXCV 81) which is an upper copy of a lost original and A House in Perspective, Lecture Diagram 36 (D17052; CXCV 82), and Building (D17053; CXCV 83) which are both lower copies of comparable originals; the original Column (D17061; CXCV 91) which was used to make Tuscan Column in Perspective, Lecture Diagram 40 (D17058; CXCV 88) as the upper copy and Perspective Construction of a Tuscan Column, Lecture Diagram 41 (D17060; CXCV 90) as the lower copy; Tracing of Guiding Lines of Diagram of Capital, Tuscan Entablature Worked Out in Perspective (D17077; CXCV 107) which was used as the original for the copies Capital, Tuscan Entablature Worked Out in Perspective (D17076; CXCV 106) and Tuscan entablature (D17079; CXCV 109); and the group discussed here.