The post-excavation work on this summer’s dig is grinding slowly on. Mostly we have been creating electronic copies of all the records, checking them for internal consistency as we go along. This is exactly as exciting as it sounds but it needs doing for two reasons. Firstly we need a secure copy of the archive, in this case held on the university’s central server, in case anything untoward happens to the actual tatty bits of paper and drawing film we used on site. It also forms the basis of all the written reports we need to produce describing the results of the excavation more formally.
So, for example, I have taken all the drawings that were done in the field and scanned them all. This gives us the secure copy of what we recorded in the field – in this case Ella’s drawing of the plan and section of ditch cut [D12] in trench D. This is the central section of the curving ditch full of posts in the centre of the monument.
I have also started to take these scanned drawings and used them for the basis of composite drawings that show all the relevent features in each trench. So far I have only completed one of these, for trench D, which joins Ella’s plan up with everyone else’s. This will be used to illustrate the interim report on all the features in trench D. As it is it nicely illustrates the central feature, which has the cut numbers [D13], [D12] and [D19], as it runs across the site. It also shows the other postholes [D14], [D10] and [D20] which aren’t part of this main feature and how they fit around it. We already know that there is more than one phase of archaeology here. The post that went into posthole [D20] had definitely been removed before the larger feature [D13] was dug.
We are getting this understanding of the detailed phases of the site from the process of checking the context sheets against the drawn record. A context is the fundamental particle of archaeology. They are the thing, like Democritus’ idea of the atom, which cannot be sub-divided into any smaller things. In practice this mean that whenever we identify a bit of physical evidence on an archaeological site for a single past event (for example the digging of a pit) then that evidence should be regarded as a separate context. Each context is given its own number and recorded on its own sheet. The system was first developed by Ed Harris in the 1960s and has become standard in archaeology since. I’ve added Harris’s book on the system onto the reading list.
One of the most important bits of information on each sheet is a record of which contexts (and hence events) came immediately before and immediately after the one being recorded. We can then try to construct a kind of flowchart called a Harris matrix which tells us in which order all the events happened. I’ve just completed Harris matrices for both trenches; the one above is for trench D.
Of course this only gives us a relative chronology for the events on site. To get a clearer idea of when and for how long the monument was in use we need to relate the finds, and eventually some absolute dating evidence such as radiocarbon results, to this structure of relative dates. So, the next post-excavation task (apart from to finish off the drawings) is to get out all the cleaned finds, check them against the site records to make sure they are what we thought they were, and make a table of which finds come from which context.