by Susan Biddle
Sarah's workshop was a great introduction to the techniques and practicalities of drawing pots. We began by completing a diagnostic ceramics recording form, describing the object (eg "handle"), and then its dimensions measured with a micrometer. By comparing a modern sherd with a rimchart (see photo), we could establish first the radius of the original pot (using the curved lines on the chart) and from this calculate its diameter, and then (using the straight lines on the chart) the percentage of the original pot which we now had.
Susan’s first pottery drawing!
We next considered the treatment of the sherd – for example, was it glazed or painted, were there any scratches? - and then how it was made. Our sherds were mould-made - that is, made using a negative mould into which the clay was pushed: some of the group could just discern finger prints where the clay had been pushed into the mould. We then recorded the colour (terracotta), and Sarah explained that the black marking visible in the middle of the broken edges of the rim showed that the kiln had not been hot enough to force all the oxygen out of the clay.
We then considered whether there was anything exciting on our sherds which should be recorded. Mine included some light coloured deposits on the inside which looked to me like flour - I was pleased to learn that I wasn't too far out, as this was bread residue from when the pot had been used as a bread mould.
The next stage was to estimate the date ("21st century" in this case) and then to record the identification number of any similar pots or pot-types. Finally we identified our own sherds with an identification number.
We then drew our sherds on graph paper - or on tracing paper over graph paper which Sarah explained was easier to scan later. We learnt finds are drawn on a scale of 1:1, and that the UK convention is to record the outside of the pot on the right hand side of the drawing, and the inside on the left. Sarah explained the aim was usually to record the type of pot, rather than a particular example.
Times haven’t changed. Patrie’s complicated apparatus to hold a vessel in order to reveal its original shape and diameter from the royal tombs of Abydos
We first marked our horizontal axis for the top of the pot and a vertical axis for the theoretical middle of the original pot. We then pressed the outside of our sherds against the fine metal teeth of a contour gauge, depressing these teeth to different depths so as to make a "stencil" which we used to draw the outside of our sherds. The benefits of mechanical propelling pencils became clear as their long leads enabled us to reflect the contour gauge more exactly than wooden pencils whose width tended to introduce inaccuracy. We next used micrometers again to mark the width of the sherd on our drawings and then used the contour gauge to make a stencil for drawing the inside edge of our sherds to join up the micrometer marks. We repeated this exercise to record the outer edge alone on the left hand side of our drawings, and then used micrometers to measure the height of the rim and recorded this. After tidying up our drawings freehand where necessary, we recorded any interesting features (such as my bread residue) and added the sherd identification number, a scale and our initials: my first pot drawing was complete!
To finish, Sarah told us a little about some of the types of clay used by Egyptians in different places, at different times, and for different purposes. For example chaff could be added to pottery intended for cooking utensils, and limestone added if a pot needed to withstand high temperatures. She explained how the "inclusions" in the clay could be used both to date it (the Egyptians added ground down pottery known as "grog" to their clay, whereas the grog added by the Romans was different) and to identify its source – for example basalt would indicate that the pot came from Canaan.
I have always admired the work of the artists and others who record finds, but after a very brief introduction to the challenges of drawing pot sherds, my admiration has at least doubled!