Tuesday 22 January 2019

Drawing and the archaeologist's dig

Archaeologist's drawing of a stone axehead

Archaeologists still make drawings of the objects they find, even though they could now scan them or take photographs of them. This is because the archaeologist provides a certain level of interpretation of a drawing, based on methods of documenting knowledge of the artefact that a camera or a computer cannot convey. In other words, the drawings are not merely artists’ renditions of the objects, but coded representations of scholarly observations. The fact that archaeologists don't find photographs give them enough information to work from is fascinating, especially in a world where the photograph has in so many ways replaced drawing as a truth statement. You are not allowed to have a drawing of yourself on your passport, but when studying artefacts the professionals would much rather be working from a drawing. So what is it about the drawing process of archaeologists that makes it so unique? A while back I posted on process and its documentation and what was interesting in relation to the documentation of the process was the need for a grid structure against which process could be measured. This is the same with archaeologists' drawings. There are some basic learning outcomes that you would need to have under your belt if you wanted to undertake some archaeological digging, the first of which relate to good practice on excavations. This is how the process is written for archaeologists.
'First of all you need to lay out a grid of 5m squares to facilitate planning. This grid is marked out on-site with grid pegs that form the baselines for tapes and other planning tools to aid the drawing of plans. In some cases, the contractor may prefer GPS located site plans and sections, but the methods of laying out a site grid, and crucially tying it into a national grid are essential.
Once a site is excavated and plans, sections and finds recorded, they have to be related to each other and a wider measurement system in order to understand where they are in a Cartesian coordinated space. In order to do this someone has to lay out a site grid with a baseline and then relate the grid to a National Grid Coordinate. The gridded trench should be laid out using right angles, often using the 3 – 4 – 5  triangle rule or using a diagonal calculator such as the one below'.
Diagonal calculator

'Coordinates are always Easting and Northing in the UK and Europe, but can be the other way round in other countries so you always need to put an E and N at the end of a coordinate to save confusion.  Set out your site grid as close to true North as you can. You can use anything from a Diff GPS to a googlemap to locate yourself. The important point is to locate yourself on the surface of the globe or your project/excavation is “floating” in space. Find at least two recognisable features that also appear on a map in order to locate your site grid such as a pylon corner, a wall or building. A very handy tool to find the Easting and Northing of Any Point on a map is to be found at:  http://www.gridreferencefinder.com  :  Just zoom in, change to Aerial View and find a Grid Reference for any point by right-clicking on the Map.  

Before you can even begin drawing you need to locate the area to a national grid co-ordinate and ensure that each square of the grid you have laid out is identifiable.
You would also need to follow the conventions of archaeological drawing, so once an item was decided upon as something worth drawing, before you put a mark on paper you would need to register the item and link that to the drawing. The main registers (archeological terminology for headings) you are likely to use are: Context, section, plan, photographic, geo-rectified photograph, level, small find and environmental. Then a photographic record shot would be taken, one with an identification board and one without.  
Photographic record of a site made before the grid is set out. Your drawing would need a reference number that could be used to link it to these photographs.
Then some geo-rectified photographs ought to be taken, these must all face in the same direction, all multiple images need to overlap and have two overlapping visual reference points, a spirit level should be used to ensure the same angle is used and record sheets completed so that cross referencing with drawings can be achieved.

There is a lot of context here that an artist would not normally think about, but if you as an artist want to situate your drawing very precisely into the context of its making, I see no reason why you shouldn't adopt the conventions of another discipline. What this process is doing though is verifying the location of the activity and by cross referencing, ensuring things like scale and orientation are understood and are clear.

An archaeologist's manual would give you the details as to how to draw cross sections of the site and to indicate the nature of the dig. See this typical archaeologist's hand-out. and this more detailed example.

Once the site itself is drawn, then the actual objects can be drawn. There are a further set of conventions for drawing small finds as laid down in manuals, such as this. What I found interesting was the use of profile gauges and calipers to ensure accuracy. This old textbook is also worth looking at in detail because as well as laying out several drawing conventions to use when drawing small finds, it gives several examples of interesting devices that can be used to help take more precise measurements. 
Using a radius card to measure a ceramic vessel 
The textbook, Griffiths, N., Jenner, A. and Wilson, C. (1949) Drawing archaeological finds: A handbook London: University College, has excellent examples of the development of specific tools to help with the accurate representation of objects. The blurb for the book states: 'This profusely illustrated volume treats the various techniques to overcome the difficulties of translating three-dimensional objects into two-dimensional illustrations'. I think it would be very interesting to make new tools of translation between three dimensions and two dimensions to help with the drawing of more contemporary situations. The need for precision is rather like the need the police have when recording a crime scene. This could be another area to investigate when thinking about applying the conventions of different disciplines to the recording of information. Above all it makes us realise that each discipline has its own representational conventions and that these are perhaps as important to the understanding of any image as what is being examined. It is only by getting to understand another discipline's conventions that we can begin to get an idea of how strange and arbitrary our own discipline's conventions are. 
Sketch of a crime scene using 'crime zone' software
The layering of information, whereby every aspect of the process is recorded and cross referenced gives an authenticity to an activity that can be used by artists to give gravitas to the processes behind the making of drawings that are often little acknowledged. You can train as a forensic artist, see details here. The most well know aspect of a forensic artist's work is of course the composite images made of suspects. 
Forensic artist's composite drawing
The text below is taken directly from an interview with a police artist.
"When something looks familiar to a victim, I include it in the drawing. If it doesn’t look right to him/her, I take it out. It’s trial and error until it all comes together. Every sketch artist has his/her own methods of procedure. It becomes personal. I’ve developed mine for over 30 years. Since so much of the sketch relies on the actual interview process, I often don’t even start to draw for the first hour. That gives the witness time to get to know me and relax. I often use relaxation/meditation techniques to calm a witness down, especially if the crime was traumatic. I was once mislabeled by the media as being a hypnotist, but I forced a retraction. While I have done some composites while a witness was under hypnosis by a trained therapist, I’m not trained to do it myself. I simply use methods of meditation to calm the mind, and make the process less stressful. All in all, it usually takes me 3 to 5 hours to complete the composite drawing". 
The police artist is looking for another way of being objective and has developed a series of techniques that rely on communication with others, this aspect of the work is also about building up reference points outside of the ones that artists normally use. Once again this process may be of use to those of you looking for alternative ways to build in objectivity into subjective experiences. In particular you might want to research 'Locard's exchange principle', which is used by detectives at a crime scene; basically it states that, every contact leaves a trace.
Nathan Coley's 'Lockerbie Evidence' is an interesting artwork that uses the conventions of a crime scene documentation to explore issues surrounding the Lockerbie plane crash.  

Nathan Coley 'Lockerbie Evidence'
The forensic investigation of artworks themselves can also lead to the making of new work, look at the Irish artist Brian Fay's drawings made from x rays of old master paintings.

Brian Fay: From Vermeer's 'Lacemaker'

Other posts related to the use of grids can be accessed from here

There is a description of how scientists think about soil analysis by Bruno Latour in his book ‘Pandora’s Hope’ and it also describes how a grid can be used to think through an analysis of the earth but it uses a different set of tools. Latour uses this approach to soil analysis to demonstrate how we can think about something in stages and that each stage can in effect belong to a totally different reality. 

Latour's text takes a while to get through but it is worth it, I have tried to simplify it in an earlier post, (See the second half of this post. ) the most interesting issue is perhaps that all drawings are to some extent about different stages and that each stage requires you as an artist to apply different thinking strategies. Sometimes you are adding, sometimes subtracting, sometimes you are discovering and at other times you are analysing, sometimes applying formal logic and at other times allowing chance to operate. 

See also:

The grid as a cage or trap
Drawing maps

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