Introduction (or, what do you do with 70kg of Roman glass waste?)
November 2, 2007 Roman glassThe site
The site at 35 Basinghall Street lies on the western edge of the Walbrook
valley, on the fringes of a marginal area, away from the main focus of residential settlement in Londinium. Before the start of the excavation we already knew that the Walbrook valley was an area of industrial activity, with the site of a major pottery workshop on the eastern side of modern Moorgate. There was also evidence for leather and bone-working and for a 2nd century glass furnace on the edge of a canalised Walbrook tributary, suggesting that this part of the town was occupied by small workshops.
Discovery
When almost 70kg of glass waste was found in the south-west corner of the site at Basinghall we were faced with a colossal task. Usually, at MoLAS, every fragment of Roman glass is accessioned (given a unique number) and recorded on our database, but with tens of thousands of fragments, this was clearly impossible.
After initial recording the first stage in the post-excavation process is always an assessment of the material, looking at its significance in relation to the site, to Roman London as a whole and, as in this case, to the wider Roman world. Clearly we had to establish rapidly exactly what we were dealing with and how much of it there was in order to devise a programme of study and research which would lead to publication.
The scale of the problem
Most of the waste came from a single context, the fill of a pit, so we sorted this, by glass colour, into the different types of waste; raw materials in the form of molten glass from the tank, which was part of the furnace and cullet, broken vessel glass which was collected for recycling and production waste.
This took various forms which I shall discuss in later postings, but the most easily recognisable fragments were molten fragments and runnels from the furnace, which had fallen on to the workshop floor, and moils, little cylinders of glass which were left on the blowing iron after the vessel was removed. Each moil therefore represents a single glass vessel and normally these fragments would have gone back into the melting pot to be blown again.
At this first stage, we accessioned only the best examples of the moils and other types of waste, and all the vessels which could be recognised by form, bagging up most of the moils as ‘bulk’ accessions. Even so, we made out over 2000 record cards. Most glass-working sites in London have produced only about a dozen moils, but at Basinghall we estimate that we have over 3,000.
The questions
There are some fundamental research questions which we are going to try to answer during our work on this project and some of these can only be answered by analysis of the glass composition, a very expensive process. We hope to work out, for example, where the raw materials came from and how they were prepared, what the glass workers were making and the techniques which they used, when the workshop operated and for how long. We shall explore these and many other detailed aspects of the glass-working industry in London over the next few months.
Having devised and costed our programme of research, we presented it to the very supportive developers of the site, Stanhope plc, who have generously agreed to fund it. We are now ready to start the programme and hope that our initial estimates will prove to be accurate!
Greg Williams :
Date: March 3, 2008 @ 11:03 pm
Angela,
Thank you for giving such a detailed insight into you work on this project.
Did I miss a talk by you on this recently in Finchley?
You might be interested in these papers on glassmaking/origins etc
Page 2:
http://www.hebrewhistory.info/factpapers/fp006-2_glass.htm
Do you know if there is any work on Roman kilns – locations, design, in the UK?
Around Edgware – a days journey from Westminster along Watling Street- there’s Brockley Hill which appears to have made enough pottery for distribution (finds) around the UK.
But there’s also something in Canons Park said to be Tile kilns.
The area became part of the estate of the Duke of Chandos, but I suspect a Roman Villa
may lie beneath the house – now a school. Ceramic tile rejects and shards have been found apparently, but no glass (so far).
Good luck with your breathtaking project
debs :
Date: March 22, 2008 @ 10:46 am
I was wondering if you can give me some advice. I have read your article with interest as when walking with my family in Wales we noticed in a patch of ploughed field adjacent to a country public footpath there were hundereds of shiny glassy looking rocks. On closer inspection the colours of these ranged from dark green through to light blue and obviously molten lumps of what we presume is glass. The lumps are from ftennis ball size to small fragments. They were very dense and hardly translucent, only a small fractured piece can light be seen thorugh. Other pieces were like swirled layers of colour, alsmost like the natural malachite stone.
We have serached the internet and local history records of the area, but the only things that come up in this area is a few rural Roman sites some miles away and near the location acient lime kilns.
Would you have any clue what these lumps of glassy stones are?
We can send you a sample.
Debs
Angela :
Date: May 12, 2008 @ 11:27 am
It is difficult to identify this sort of thing without seeing it, but it is very unlikely to be anything to do with Roman glass-working. It could be from a much later industry, or it might be geological.
You don’t say which part of Wales you found this material, which sounds very interesting, but the best thing would probably be to take a sample to a local museum for identification. They would know more about the geology of the region and might be able to help you.
Angela :
Date: May 12, 2008 @ 1:31 pm
Greg,
Thank you very much for your comments — sorry for the long delay in replying – its all been pretty busy here and I have fallen behind with the blog. No, I have not given a talk in Finchley, although I am about to speak to a society in Hendon on this and other topics.
We have evidence for other glass-working sites in several places in Roman London, among them evidence for kilns (not reconstructable) in the area of modern Old Bailey, but as far as I know Brockley Hill produced only pottery. John and I are working on a booklet about the Basinghall Street site which will summarise the London evidence — to be published later this year.
There has been much work recently on the design of kilns and Roman glass-working techniques in general by the Roman glassmakers, Mark Taylor and David Hill http://www.romanglassmakers.co.uk/. They have a fascinating and very informative website, with pictures of their experimental furnaces. Well worth a look!