Giovanni Antonio Dosio (1533–1609), Plans and details from an album, after 1550. Ink on oiled paper, 300 × 420 mm.
Tightening the belt, lean-manufacturing, ‘trimming the fat’. These are guiding principles of instrumentalised, technocratic systems termed by French sociologists as dégraissé – translated literally ‘degreased’ or ‘defatted’, but also figuratively understood as streamlined, purified and uncontaminated. 
Instinctively, however, we know that flavour resides in fat. Thoughts of feasting, and midwinter delicacies, wallow in images of warmth, security and protective layers of lard. These associations are also embroiled in the surfaces we use to make drawings. Presentation drawings – clean, opaque and unsullied – project a distilled and immaculate imaginary, a clarified arrangement on a smooth and impenetrable substrate. But what, then, of the drawings under the surface? Those where thinking happens, with their fingerprints, smears and smudged dog-eared leaves, dead ends and miraculous mistakes? Something is revealed in the furtive ooze of these translucent marks. With them, we begin to see through.
The sheet under discussion is one of a number of drawings made on oiled paper contained in the sixteenth-century album attributed to Giovanni Antonio Dosio. A compilation of copies after the antique, the volume is a repository of reference drawings made both in, and through, the glutinous gluttony of the medium.
Of the three possible methods used to increase light transmission in paper, oiling is the oldest.  Oiled paper is prepared by immersing, daubing or painting oil onto its surface in order to render it translucent, and the use of oiled paper in the Dosio album indicates that these drawings are tracings.  In order to follow this, one must imagine the compressed fibres of the paper as a conglomeration of shredded material separated by almost invisible pockets of air. It is the air between the fibres that allows light to be reflected back at the eye, rendering the paper opaque. By aligning the refractive index of the gaps with the refractive index of the cellulose (ie, filling those gaps) the light is transmitted through the paper, and in turn the paper is perceived as transparent.  In preparation and use, this tracing paper is both conceptually and materially absorbent: enabling the ingestion of ink and ideas – of other drawings, other notions, other worlds. Its oleaginous surface siphons these ideas and moves them about. The fattiness of this surface is fertile ground.
Age, however, has an effect on the polymerisation process, in which refractive indexes are known to increase, causing the paper to become more opaque. Porous cells lie plugged with oil, much like the plans isolated on the surface of this spread, each void held in positive tension by the circumcising lines. As such the transparency of these treated surfaces is sometimes temporary; the fat solidifies and masks our entry into prior procedural emulsifications. The paper now dry, brittle, nut brown and crackling under my fingertips, no longer holds the filigree pliability associated with its youth. This capacity to hide and to reveal complicates its designation in many archives as a secondary, ephemeral and notorious unstable medium. And so to return to the drawings means also to return to the methods by which they were made.
We see how the oil has sunk into the creases of this sheet, how it moves along the interstices, gathered at the folds. We note the darker zones where fat has pooled, where splotches reveal fibres more or less accommodating to the inundation. Where the pages have been turned at the bound edge, we note a dragon whose fiery breath sears across the fold, the very tip of one wing severed by the binding. This may designate the appetite of the album format, which sharply bends a large sheet into bookshelf-scale submission. There are losses here too, with brittle central fragments now failing to jigsaw appropriately.
Looking at this spread, one can sense a breathlessness in the accrual of lineaments, a veritable cramming of the available space, a hoarding for winter. With each repositioning, the space of the page is negotiated, boundaries determined and repetitions adjusted. Once lifted and displaced it gains autonomy, capturing notions afresh, allowing new ideas to enter, interrupt and solidify. Drawings such as these do not respect conventions, positions, rules… their figures jostle, their arrangements are ambiguous, composite. They disturb hierarchies, deny classification, ignore order. And while the numbered measurements suggest these tracings are based on other drawings of built things, they also contain a logic that deals with the shifting (and contradictory) forces of power, disgust and desire. We note particularly the half drawings, the grotesques folded half out of view, rendered invisible at their hinge points.  Their accruals do not unfold along a linear trajectory but are rather in constant motion, reflecting the back-and-forth strategies of making and remaking, and of connecting and disconnecting with buildings and their representations. This reciprocal motion is fundamentally concerned with relating – to one’s own work, to the work of others, and to the world.
Counterintuitively, this transparent paper is fuller – fatter – than its opaque counterpart. Fat is penetrative, seeping, easily absorbed. Fat can both elevate and contaminate. Thinking about the album as a fatty substance, we begin to see it as visceral as well as visual, a communicative medium, brimming with unctuous half-thoughts secreted between its fibres.
– Laura Harty
Christopher, E Forth, Fat, A Cultural History of the Stuff of Life (London: Reaction Books, 2019)
Cennino Cenni refers to linseed oiled paper in his fourteenth-century treatise Il Libro dell’arte. The other two later methods involve: immersing the paper in an acid which causes the fibres to swell and reduce the air pockets (parchment paper, a nineteenth-century innovation, often used to contain fat – such as in food wrapping – giving us Butter Paper ); and mechanically blitzing the paper pulp so that miniscule fibres fill the gaps (overbeaten paper: its genesis is less clear. It may have been limited circulation at the close of the eighteenth century, but its development is closely linked to mechanised production methods of the nineteenth century. Generally speaking this is the tracing paper with which we are familiar today). See Claude Laroque, ‘History and analysis of transparent papers’, The paper Conservator, 28:1, pp 17–32 (2004).
Campbell, Nesselrath, MacGregor, Montagu, McBurney, and the Royal Collection, Ancient Roman topography and architecture (Paper museum of Cassiano dal Pozzo, series A, part 9), volume 3, entry 33 (London: Royal Collection), p 846.
A relationship determined by Snell’s law (1621): n2/n1 = sin x1 / sin x2 . Note that the paper had to be fully dried, ideally externally to avoid rancidity, and later surface sized to avoid the bleeding of inks. See L Olcott-Price, Line, shade, and shadow : The fabrication and preservation of architectural drawings (Oak Knoll Press, 2010), p 81.
Campbell, Nesselrath, et al, Ancient Roman topography and architecture, vol 2. The practice of tracing half and completing the symmetrical arrangement later was common practice among sixteenth-century copyists, a nod toward our lean contemporary draughting process.