Th e systematic application of scientifi c techniques to questions relating to industries of the post-medieval and industrial periods is a recent phenomenon. Th e focus of this chapter is on using materials science to answer archaeological questions. Some commonly used analytical techniques are briefl y described, and case studies are used to demonstrate the application of these techniques to archaeological glass and glassworking sites. Th e problems and opportunities of excavating post-medieval industrial sites are summarised. During this period glass furnaces changed from wood to coal as a fuel, and the form of the structure changed and increased in size. Two contrasting 17th-century glasshouses, at Shinrone and Silkstone, are used as examples of the benefi ts of scientifi c investigation of excavated fi nds. Many diff erent compositions of glass were made during this period, and the changes demonstrate alterations (usually improvements) in quality. For some types of glass a suffi ciently large database of analyses exists to permit the composition to be used as a dating tool.

Science for Historic Industries – Glass and Glassworking

INTRODUCTION

Scientifi c techniques are regularly used in archaeological investigations of medieval and earlier sites, but their systematic application to questions relating to industries of the post-medieval and industrial periods is a recent phenomenon.1 Th ere are many diff erent techniques that can be used, running from geophysical prospection and scientifi c dating methods such as dendrochronology and thermoluminescence, to the range of biological and earth sciences collectively known as environmental archaeology. Here the focus is on materials science, which uses many diff erent physico-chemical techniques to answer archaeological questions, largely by analysing inorganic materials such as glass, ceramics, metal alloys, chemical residues and waste slags.

THE PROBLEMS AND OPPORTUNITIES OF INDUSTRIAL SITES

Th e upsurge in excavations of ‘brown-fi eld’ sites prior to redevelopment has provided an opportunity to develop existing techniques – both archaeological and scientifi c – so they are better suited to the large scale of the structures and deposits that are often encountered. Th ere was no history of using scientifi c investigative techniques in industrial archaeology, although many of the structures and machines that were surveyed and recorded were examples of the application of 18th- and 19th-century science and engineering. In order

By JUSTINE BAYLEY, DAVID DUNGWORTH & SARAH PAYNTER

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to help those archaeologists who were trained mainly on sites of earlier date but are now excavating post-medieval industrial sites, English Heritage has recently published a guidance document that contains examples of the application of a wide range of scientifi c techniques to these types of sites.2 Th e problems encountered are diff erent from those at earlier periods for a number of reasons.

Th e fi rst is the scale of industrial features, as many historic industries operated in very large structures and used huge quantities of raw materials. For example, in the 16th century the furnaces used for making glass typically had a footprint of less than 20m2 but in later periods, the furnaces became larger and larger until by the mid-19th century the footprint was over 100m2. Conventional trial trenches or test-pits will usually be too small to make any sense of features on this sort of scale. Th e quantities of raw materials were equally large, and huge quantities of waste materials were generated as well as the desired product. To give an idea of scale, a late 18th-century blast furnace typically produced 2000 tons of cast iron each year, and at least 1000m3 of slag. If this had been dumped in a conical heap beside the furnace, the heap would be taller than the blast furnace in less than a decade, and after two decades or so the blast furnace would be in danger of being engulfed by its own slag heap.

Despite the quantities of waste produced, many industries continue to operate on the same site for extended periods. Th is was possible because many of the process residues could be sold on as raw material for another industry. In the 18th and 19th centuries, the bottle glass industry increasingly made use of waste from the iron, soap and gas industries as raw materials,3 and in turn some of its waste was used by the brass casting industry and in the manufacture of alum and saltpetre.4 Th is recycling does, however, add a further diffi culty to interpreting excavated assemblages as some process residues are under-represented or even missing from the archaeological record.

Th e waste that could not be recycled was often used to raise ground levels. Many areas of our historic towns are built on fl ood plains, but the ground levels are often a metre or more higher than they were in the medieval period. Th e outcome for archaeologists is that many of the waste products will be missing from a production site, but they can instead turn up in made ground on sites where completely diff erent industries were carried out. Before the advent of canals, and especially railways, bulk transport of materials was diffi cult and expensive so movements were over relatively short distances, but in the 19th century slags, for instance, were used as raw materials in many civil engineering projects and were transported over considerable distances.

A potential argument against the need to use the techniques of archaeological science, or even excavation, for industrial sites is that documentary sources contain all the answers. In rare cases this can be so, but the surviving documentary records were mostly made by the owners of sites and so focus on money, building-plans or specifi cations of large pieces of equipment rather than the day-to-day details of people and processes. Plant was often modifi ed when the original structure failed to work in the expected way (as with the Hotties5), so the surviving plans do not fi t the archaeological remains. Th e terminology used in documents may be obscure, for instance, the 17th-century glassworks at Silkstone (see below) are described in a will as having a green house and a white house – referring to

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the colour of the glass produced.6 Industrial espionage was widespread in the early modern period, so some documents may contain deliberately misleading accounts.7 Sometimes the travel diaries of these ‘spies’, for example that of the Swede, Angerstein, can be a useful source of information.8 Even in the few cases where technical details have been recorded, these often focus on the raw materials and the products,9 which are often absent from the archaeological record, rather than on the process residues. It is certainly true that ancillary activities are very rarely recorded; at Derwentcote, County Durham, the only evidence for processes other than cementation steel-making came from analysis of the slags.10 Th ere is thus a real role for science in fi lling in the details of the whole range of processes carried out on a particular site, processes that were often continually modifi ed by those working there.

SCIENTIFIC TECHNIQUES AND THEIR APPLICATION TO HISTORIC GLASSWORKING

Science cannot provide a panacea, but it does give an objective measure of what is present and can demonstrate how materials were produced. It can add to the interpretation of the archaeological deposits, but only if there is good liaison between all the specialists working on a particular project. Th e major role for materials science is in trying to reconstruct historic industries through the examination of process residues. Th e techniques used are similar to those employed in modern industrial studies where people want to understand how a production process went wrong. It is desirable to examine the whole range of raw materials and products, but even when these are not all available considerable progress can be made.

A number of diff erent microscopic and analytical techniques are used routinely. Chemical analysis usually determines which elements are present in a sample or object, and in what quantities, though sometimes techniques are used that can identify the compounds present. It is the question that is being posed that determines which technique is used.

Microscopy provides enlarged images. Particularly useful is a scanning electron microscope (SEM) as it can work at high magnifi cations while still giving a good depth of fi eld for a 3D object, features that cannot be combined in a conventional optical microscope. Th e SEM can also produce images where the contrast is due to diff erences in composition (Fig. 10.1a). Th e SEM becomes a really powerful tool when a method of chemical analysis (energy dispersive X-ray fl uorescence (EDX)) is integrated into it. Discrete areas or particles can be analysed, and changes in composition across the sample can be mapped (Fig. 10.1b). Th e SEM–EDX cannot detect the trace levels of elements that some techniques can achieve but it is nevertheless a very powerful tool for understanding process residues.

Th e potential of scientifi c techniques to contribute to integrated historical and archaeological projects investigating post-medieval and later industries can be illustrated by a number of recent projects relating to glassworking. On glass production sites the aims of the scientifi c investigation are normally to identify the raw materials and fuel used; to determine the composition(s) of the glass being made; to identify the products being manufactured from it; and to say something about the furnace conditions. Th e data

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obtained can then be compared both with information from any documents that relate to the site, and with scientifi c data from other glassworking sites as is demonstrated below for Shinrone and Silkstone.

Scientifi c analyses have also provided information that complements and expands conventional studies of glass artefacts. Th e aim is usually to identify the type(s) of glass used to make them, and then to relate this compositional data to their chronology or context. Th e examples below deal with early lead crystal drinking glasses and with the changing technology of window glass production.

Many diff erent types of glass were produced in the late medieval and later periods, and most of these are mentioned in the examples below. All these glasses were based on silica, which was normally in the form of sand but sometimes calcined and crushed fl int was used instead. It was important that the sand had a low iron content if the glass was to be colourless, though dark green glass could be made from less pure ingredients. Prior to the introduction of synthetic alkalis (see below), ashes from plants were usually the other major constituent. Th ese contained variable amounts of alkali, that is soda and/or potash,

Figure 10.1a Backscattered electron image showing the interface between a crucible and the adhering layer of glass. Note the darker-coloured interaction zone between the glass (light) above and the heterogeneous ceramic below.

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which act as fl uxes, strongly infl uencing the melting and working temperature of the glass. Sometimes lead oxide was used as a glass fl ux, for example, to produce lead crystal glasses. Th e glass of this period can contain a large amount of lime, introduced unrecognised with either the sand or plant ash. When glassmakers purifi ed their raw materials in an attempt to make good colourless glass they often reduced or even eliminated the lime, so the glass they made suff ered from crazing and crizzling and was not durable.11

GLASSWORKING AT SHINRONE, COUNTY OFFALY

An upstanding 17th-century wood-fi red glasshouse survives at Shinrone, County Off aly. Two seasons of excavation were carried out at the glasshouse by Caimin O’Brien and Jean Farelly, and glassworking waste and products were recovered, samples of which were

Figure 10.1b Analyses made along a line running from the unaltered glass down into the crucible in Fig. 10.1a, showing how the glass and crucible interact. Care must be taken to avoid the interaction zone when analysing glass adhering to crucibles or the results will not represent its true composition

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analysed by Sarah Paynter. Th e fi ndings are described in full elsewhere.12 Documentary sources provide a context for the scientifi c investigations. In the later part of the 16th century glassworkers from Lorraine and Normandy came to England, bringing with them a glassworking tradition that diff ered from that then in use.13 Th e glass made by the immigrant glassworkers was harder, brighter and less susceptible to weathering than the glass manufactured previously by English glasshouses. Analyses have shown that the glass made by the French glassworkers contained higher concentrations of lime and lower levels of potash relative to the earlier English-made forest (potash) glass, so the former is often referred to as HLLA (high-lime low-alkali) glass. Some members of these French glass-making families subsequently relocated from England to Ireland, and were in the Shinrone area in the 17th century.

In 1615, Sir Robert Mansell was awarded a monopoly on all types of glassmaking in England, while the use of wood fuel by the industry in England was prohibited.14 Glass production at Shinrone is likely to have commenced at about this time, encouraged by the monopoly in England, and ceased around 1641 when a bill was introduced to prohibit the felling of trees to fuel glass furnaces in Ireland. Th e exceptionally preserved Shinrone glasshouse is an invaluable source of information on the glass industry, not only for early 17th-century Ireland but also for England in the previous half century when wood-fi red furnaces were still in use, as the archaeological remains in England are sparse in comparison.

Figure 10.2 Bar chart showing composition of glass made at Shinrone and Glaster compared with other bottle, vessel and window glass found at Shinrone

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Th e fi nds assemblage from Shinrone comprised two visibly distinct types of pale green window glass (one with iridescent weathered surfaces), vessel glass, lumps and dribbles of glass, bottle glass, droplets of transparent blue glass, crucible fragments and furnace fragments. Small samples were removed from examples of all these classes of fi nds and were analysed using an SEM–EDX. Th e type of glass being made at the site was characterised by analysing dribbles and lumps of glass, likely to have been discarded during glassworking. Th e Shinrone glass had an HLLA composition, but it was subtly distinct from the HLLA glass produced at a nearby glasshouse at Glaster and also at glasshouses of various dates in England. It was therefore possible to distinguish the objects that had been made at Shinrone from those that had been brought to the site by comparing their compositions with the Shinrone glassworking waste (Fig. 10. 2). Th e pale green window glass with iridescence and the majority of the vessel fragments from the site were all made from Shinrone glass, indicating that both windows and vessels were being produced at the site. Th e pale green window glass (without iridescence), all of the bottle glass and several pale olive fragments of vessel glass were made elsewhere.

Th e furnace was constructed from sandstone and the internal surface was covered in a transparent blue glaze, which analysis showed was rich in potash. Th e glaze had been produced by the reaction of potash-rich waste gases from the burning wood fuel with the silica-rich sandstone.15 Small droplets of blue potash-rich glass that formed when drips of glaze fell from the interior surfaces of the furnace onto the fl oor below were also recovered from the site. Th e presence of this potash-rich glaze confi rms the use of wood fuel at Shinrone.

Large sherds of used crucibles were found, made from specialised refractory clay and tempered with quartz (sand) and grog. With use, both the internal and external surfaces of the crucibles had become unintentionally glazed by drips of the glass being melted in them as well as by interaction of the crucible ceramic with the potash-rich vapour from the wood fuel. None of the glassy deposits in the crucible fragments analysed had compositions exactly matching the glass originally contained in them, owing to contamination from the crucible ceramic and the fuel vapour.

Previous work has established that HLLA glass was made from plant ashes, but these have a very variable composition, depending on factors such as the species of plant, the geology where the plant is growing, the part of the plant, the time of year and the temperature used for ashing.16 Species such as oak and beech are known to produce lime-rich ashes17 and the ratios of elements present in the oak ash are comparable to those in the Shinrone glass. Th e woodland in the Shinrone area was predominantly oak according to records18 so oak ash combined with sand are likely to have been the major constituents of the glass made there. Th e HLLA glass made at Shinrone and Glaster contains much less phosphorus (<1.8% P2O5) and manganese (<0.31% MnO) than HLLA glass from English glasshouses. Both of these elements are derived predominantly from the plant ashes used to make the glass, and this diff erence may be attributable to the geology of the region where the plants were grown.

Th e temperatures necessary to melt samples of HLLA archaeological glass have been

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experimentally determined.19 Similar temperatures of around 1260–1290°C would have been necessary to melt the Shinrone glass, and the temperature attained in the furnace may have exceeded this slightly.

GLASSWORKING AT SILKSTONE, YORKSHIRE

Documentary sources indicate that there was a glasshouse at Silkstone in the second half of the 17th century, but unlike Shinrone no above-ground traces have survived and until recently the exact location of the glasshouse was unknown. Since then, excavation and a programme of scientifi c research have provided a wealth of information about this glasshouse.20 It was built in the late 1650s and continued in use until the end of the century; the documentary sources do not provide an exact date for the end of glass production, but the archaeological evidence points to c. 1700. Th e excavation found no in situ remains of the furnaces but did uncover a deep stratigraphic sequence. Th is consisted of two working fl oor surfaces composed of tiny fragments of coal and glass waste separated by a layer of demolition rubble. Th e fl oor surfaces appear to have accumulated within a glasshouse, and the furnaces can only have been a few metres away from the excavated trench. Th e fi rst fl oor surface probably belongs to the 1660s or 1670s, but the second is fi rmly dated by associated clay pipes to the last two decades of the 17th century.

Th e excavation recovered substantial quantities of glassworking waste, and the decision to take soil samples from the working fl oor surfaces allowed the recovery of almost microscopic residues such as tiny threads and droplets of glass. Th e waste all falls into two broad groups based on colour: a dark green glass, which was used primarily for the manufacture of wine bottles, and colourless (or very pale green) glass, which was used to make drinking glasses and other tablewares. Th e production of both types of glass is also indicated in one of the written sources, which refers to the green house and white house (white in this context meaning colourless).21 Chemical analysis has shown that the dark green glass was a HLLA glass of the same type that was made at Shinrone. Th ere are minor diff erences in the composition of this glass in the diff erent phases of production at Silkstone, but these do not appear to be of great technological importance. Merrett, writing in the 1660s, describes dark green glass as being made from many diff erent plant ashes (in addition to sand) and that there was a trade in these ashes to supply glass manufacturers and other industries.22 Isotopic analysis of samples of this glass indicate that at least some raw materials came from far beyond Yorkshire – indeed, the closest areas with similar isotopic ratios are Wales, the Lake District and Scotland.23

Th e analysis of the colourless and pale green glasses used to make drinking vessels reveals signifi cant technological change between the two phases of production. In the fi rst phase the glass is a pale green mixed alkali glass, which is characterised by a high strontium content (Fig. 10.3). Th e strontium content (and its isotopic ratio) indicates that the plant ash used was seaweed or kelp.24 Seaweed is known to have been widely used in glassmaking in the 18th and early 19th centuries, but Silkstone provides the earliest evidence for its use – perhaps surprising given that Silkstone is 90km from the coast. In the later phase of glassmaking the old recipe for the manufacture of glass used in making tablewares was abandoned in favour of a lead–potash–silicate glass (usually called fl int glass in contemporary

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sources). Th e research at Silkstone showed that little was known about the composition of early fl int glass and the role of George Ravenscroft who was credited with its invention.25

Subsequent research into fl int glass (see below) indicates that Silkstone adopted this new type of glass very quickly. Ravenscroft’s patent did not expire until 1681, but the new glass was being produced in Silkstone from c. 1680 (possibly even infringing the patent).

LEAD CRYSTAL

Th e research into the compositions of the Silkstone glassworking debris showed the early introduction of a lead–potash–silicate (fl int) glass. Despite the signifi cant economic role of this glass, very little scientifi c research had been undertaken previously on its origins. Merrett writes in the 1660s that ‘Glass of Lead, ’tis a thing unpractised by our Furnaces … And could this be made as tough as that of Chrystalline ’twould far surpass it.’26 Th e invention of fl int glass is traditionally attributed to Ravenscroft who obtained a patent in 1674. Unfortunately, the patent provides little specifi c information: it describes the glass as simply ‘a particular sort of Cristaline Glasses resembling Rock Cristall’27 and does not mention any of the ingredients used. A number of contemporary sources suggest that the glass was made using a variety of materials, including quartz pebbles, fl int, sand, borax, tartar and saltpetre.28 A programme of chemical analysis has now investigated samples of vessel glass of this period, in particular several examples of vessels that bear a raven seal,

Figure 10.3 Scatter plot of Na2O vs SrO for Silkstone glass. Th e raised strontium content of one of the Phase 1 mixed alkali glass shows it had been made using seaweed (kelp) ash.

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ABOVE: Figure 10.4a PbO vs K2O for early lead crystal glass, showing four compositional groups.BELOW: Figure 10.4b Correlation of composition with date for early lead crystal glass. Th e groups are the

same as in Figure 10.4a.

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which are believed to have been produced by Ravenscroft’s glasshouses. Th e vessels were made using two diff erent types of glass: some were soda-rich alkali glasses with compositions similar to those produced in Venice at this time, and some were lead–potash–silicate glasses. Glasses of similar compositions to the Ravenscroft lead glass (Group 1 in Fig.10.4a) are also represented by vessels with no seal or with other types of seal, and some of these are likely to have been produced by other glasshouses. Unfortunately the practice of using seals was not introduced until 1676 and it has not been possible to positively identify any of Ravenscroft’s early vessels (that is, those from 1674–6). Th e proportions of lead and potash in the Group I glass did not provide a stable glass (all extant examples have suff ered from corrosion or crizzling) and after Ravenscroft’s patent expired, fl int glassmakers increased the proportion of lead and reduced the proportion of potash to rectify this (Figs 10.4a and 10.4b).

WINDOW GLASS

Window (and other fl at) glass was manufactured using a variety of forming techniques and ingredients depending on its intended use. In addition, techniques and ingredients changed over time as new technologies were developed. Th e composition of window glass refl ects the nature of the ingredients used, and it often has little to do with the forming technique. Th e window glass of the 16th and 17th centuries is usually a HLLA glass, which diff ers little from that used for the manufacture of bottles and common drinking vessels (Table 10.1, Fig. 10.5a). Th e analysis of window glass produced after c. 1700, however, shows that a signifi cant change had occurred in the ingredients used. For the rest of the 18th century and the fi rst few decades of the 19th century almost all window glass was a mixed alkali glass (Table 10.1). One of the most distinctive aspects of the composition of this mixed alkali glass is the relatively high levels of strontium oxide. Th is oxide is likely to derive from the use of kelp as the principal fl ux in window glass manufacture. Th e widespread use of kelp in the glass industry in the 18th and early 19th centuries is corroborated by documentary evidence.29 Muspratt also makes it clear that the use of kelp came to a dramatic end in the 1820s owing to the availability of synthetic soda. Nicholas LeBlanc had developed a technique for converting common salt into sodium carbonate at the end of the 18th century but this was not introduced into Britain until the 1820s. Nineteenth-century window glass produced after c. 1820 is almost always a soda-lime glass, which unlike the HLLA and mixed alkali glasses contains low levels of impurities (Table 10.1).

Table 10.1 Typical compositions of window glass manufactured in England c. 1600 to c. 1920

Type and period Na2O MgO Al2O3 SiO2 P2O5 K2O CaO Fe2O3 SrO

HLLA c. 1570–c. 1700

3.3 3.1 2.7 61.5 2.0 4.0 20.0 1.5 0.10

Mixed-alkalic. 1700–c. 1820

9.4 5.4 3.1 66.2 0.3 4.3 8.8 0.7 0.40

Soda-lime (synthetic) c. 1820–c. 1920

12.0 0.3 1.5 72.3 <0.2 0.6 13.2 0.2 0.05

Data from Mortimer 1993; Dungworth 2006; Turner 1926.

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PALACE HOUSE MANSION, NEWMARKET

An unexpected discovery during the course of restoration work at Palace House Mansion, Newmarket in 1996–7, was a late-17th-century sash window, complete with much of its original glass. A long red brick range (including the window) had been added to the property in 1671, just three years after it had been bought by King Charles II as a hunting lodge. Because of subsequent alterations to the building, part of the window had been cut away by the early 18th century; it had only survived because it had been sealed behind new brickwork during further alterations in the 19th century.30

Th e window (2.75 by 1.5m) is made of oak and is divided into four equal quarters. Th e glazing in the upper part was fi xed, but the two lower quarters were rising sashes, only one of which survives. Th ese were counterbalanced on one side only by cylindrical lead weights that were strung, like beads, on a fl ax sash cord. Th ree glazed panels were found. Th e largest is in the sash and is made up of fi ve rows of three rectangular panes (the central ones being 240 by 180mm) set in lead cames. Above this, part of a panel of fi xed glazing survives with two rows of three panes. On the other side, above the lost sash, is another fi xed panel of leaded diamond-shaped panes. Th e panel with diamond-shaped panes would have been part of the original glazing scheme, which was blocked off when the sash below it was cut away to make a doorway. Th e other half of the window appears to have remained in use and was reglazed with panels made of rectangular panes, possibly when the alterations were made in the early 18th century.

Figure 10.5a Chronological range of diff erent compositional types of window glass. Th e grey zones are known from analyses of dated window glass while the white ones show the pattern that is expected to emerge from future work

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All the panes have a range of pale greenish tints and appear to be cut from slightly bubbly cylinder-blown glass. Analyses were made of samples from nine of the diamond-shaped panes and from nine of the rectangular panes from the smaller of the two panels. All the glass has a HLLA composition, though there are slight diff erences between the diamond and rectangular panes (Fig.10.5b). Th ese diff erences may be due to diff erences in date, or just the use of glass from diff erent production sites.

Th e building was a royal hunting lodge, and the window was in the king’s bedchamber,31 so the glass might have been expected to be the latest type which, according to data collected in the English Heritage Archaeological Science Laboratory (Fig.10.5a), should have been a mixed-alkali glass. Th e HLLA composition of the glass is thus somewhat surprising as it would have been less transparent, and somewhat darker in hue than mixed-alkali glass. Th e window falls right at the end of the period when HLLA glass was regularly used for glazing windows; perhaps better glass was not available in Newmarket at the time the building was erected and then modifi ed, some while later.

CONCLUSIONS

Th is review of the contribution that materials science can make to the archaeology of the post-medieval and industrial periods has demonstrated that materials science can help to identify wastes and residues, and hence the processes carried out on particular production sites. Th e scientifi c investigation can also identify the raw materials and fuel used, the composition of the products made on site, and provide information on process variables that cannot be obtained by conventional archaeological or historical research.

Figure 10.5b Th e composition of window glass of two phases from Palace House Mansion, Newmarket.

CROSSING PATHS OR SHARING TRACKS?130

Th e local raw materials used at the late wood-fi red furnace at Shinrone were identifi ed, and the products of the furnace could be diff erentiated from glass objects brought to the site, and even from glass made at Glaster, a nearby contemporary glasshouse. Th e slight diff erences in composition between HLLA glasses produced at diff erent glasshouses also illustrates the potential of glass compositional data as an aid in determining where glass was made. Th e contamination of glass remaining in the crucibles was demonstrated, and explained. Th at the glass was all HLLA is not surprising as the individuals who are known to have worked the site were from immigrant families who had brought this technology to England in the previous century. Silkstone, in contrast, emerges as a glasshouse with far-reaching economic and technological links. It produced a range of tablewares and bottles using raw materials from coastal areas and some region in the north or west of the British Isles. Despite its provincial location, the glassworkers were quickly aware of, and adopted, the latest technology in the form of fl int glass.

When studying the products of the glass industry, scientifi c analyses provide information on composition. With growing datasets this information has the potential to feed back into mainstream archaeology by dating fi nds or associating them with a particular manufacturer or source area. Th e very short-lived changes in lead crystal composition (Fig.10.4b) are one example of this, and on a longer time-scale the changes in window-glass composition (Fig.10.5a).

Th is technical information cannot stand on its own but has to be combined with other archaeological and historical research to provide a holistic picture of the past, as the examples above have shown. To be successful, this requires dialogue and interchange of information between the diff erent specialists working on particular projects so they can capitalise on the new information and fully interpret it.

Archaeology must tell stories about the past, providing not only technical details of industries but information about the people who owned them or worked in them; industrial sites did not operate in a social vacuum. Science has the potential to contribute to this wider picture too. When a suffi cient body of scientifi c data has been amassed, it should be able to illuminate the distribution and use networks that led products of industries to their fi nal resting places – after they had been transported, bought, used and discarded by people in the British Isles and beyond.

ACKNOWLEDGMENTSTh e authors would like to thank John Vallender for his help with the illustrations.

Bayley & Crossley 2004; Bayley & Williams 2005.Dungworth & Paynter 2006.Berg & Berg 2001, 129; Pellatt 1849, 33.Muspratt 1860, 206.Krupa & Heawood 2002, 86.

1.

2.

3.

4.

5.

NOTES

Dungworth & Cromwell 2006, 162.Charleston 1984, 111–13.Berg & Berg 2001.e.g. Parkes 1823.McDonnell 1997, 93–100.

6.

7.

8.

9.

10.

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Cable 2001, 211; Hurst Vose 1980, 113.O’Brien, Farelly & Paynter 2005.Kenyon 1967, 13–14; Godfrey 1975, 33–7; Crossley 1983.Godfrey 1975, 68.Misra, Ragland & Baker 1993.Sanderson & Hunter 1981; Stern & Gerber 2004.Turner 1956, 290T; Sanderson & Hunter 1981, Table 1; Stern & Gerner 2004, Table 1.O’Brien pers comm.Cable & Smedley 1987.Dungworth & Cromwell 2006.

11.

12.

13.

14.

15.

16.

17.

18.

19.

20.

Ashurst 1987.Cable 2001, 322–3.Dungworth, Degryse & Schneider (forthcoming).Dungworth, Degryse & Schneider (forthcoming).Charleston 1984, 110.Cable 2001, 373–4.MacLeod 1987, 789.Dungworth & Brain 2005.Buckley 2003, 91; Parkes 1823, 192.Baggs 1997.Baggs 1997.

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27.

28.

29.

30.

31.

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