Fire beneath the trees
During the sixteenth century, furnace fires burned in clearings within Sidney Wood. Men carried timber, clay pots, sand and broken glass along woodland tracks. Molten glass gathered on iron tools glowed at the furnace mouth, while finished vessels and circular sheets of window glass cooled in a separate annealing chamber.
Alfold belonged to the great glassmaking district of the Weald, extending through south-west Surrey and north-west Sussex. Chiddingfold had become an established centre by the medieval period, and glasshouses later spread through the wooded country towards Wisborough Green. Sidney Wood offered the space, fuel and water required for a demanding industry whose products travelled far beyond the parish.
The glasshouse was an organised industrial workplace. Furnaces, stores, clay pits, working floors, cullet heaps and waste tips occupied the clearing. Glassblowers worked alongside furnace builders, clay workers, woodcutters, carters and labourers. Their combined skills linked a secluded wood with merchants, builders, householders, churches and medical practitioners.
Why Sidney Wood suited glassmaking
Glass production required sustained heat. Coppiced woodland supplied a renewable flow of fuel, and wood ash provided potash that acted as a flux within the glass batch. Silica-bearing sand or stone supplied the main glass-forming material. Clay was shaped into crucibles and used in furnace construction, while streams supported washing, drainage and the daily needs of workers and animals.
Coppice management created a cycle of cutting and regrowth. A glasshouse could draw fuel from a wide area and then move or rebuild as supplies and structures changed. Carters brought raw materials to the clearing and carried finished glass towards Guildford, Sussex markets and London. The same woodland economy supported ironworking, charcoal burning, building and agriculture.
Sidney Wood also lay within an established framework of ownership, tracks and streams. Its industrial sites occupied selected banks and clearings rather than an undivided forest. The position of Knightons above a stream offered a firm working terrace, a nearby watercourse and access through the western edge of the parish.
Knightons in the 1550s
The best understood Alfold glasshouse is Knightons, close to the western parish boundary near Dunsfold. Pottery, glass forms, archaeomagnetic evidence and the coin found within the annealing furnace place its principal activity in the middle of the sixteenth century. Surrey Archaeological Society later described the workshop as operating in the 1550s.
The site changed during its working life. Excavators identified several furnace structures and rebuilding phases. Two rectangular working furnaces occupied the main production area, and one was reconstructed after an earlier phase. A separate horizontal, two-chamber annealing furnace served the production of crown window glass.
The layout reveals investment and planning. Stores held sand and broken glass, clay pits supplied furnace material, and a waste area received fragments of crucible, fused stone, ash and failed products. Evidence for a covering structure suggests that part of the workshop was protected from rain while workers controlled temperatures and handled fragile glass.
Furnaces, crucibles and a working day
The rectangular melting furnace contained a central flue and positions for large clay crucibles. Prepared ingredients and recycled glass were heated inside these pots until they fused into a workable mass. The glassmaker gathered molten glass on the end of an iron tool, rolled and reheated it, introduced air through a blowpipe and shaped the object through turning, blowing, cutting and tooling.
Furnace heat placed severe demands on the structure. Clay, sandstone and other materials became scorched, glazed or fused. Crucibles cracked after repeated firing, and furnaces required repair or rebuilding. The successive structures at Knightons record this cycle of intense use.
Finished glass entered the annealing furnace, where it cooled gradually. Controlled cooling relieved internal stresses and reduced breakage. At Knightons the two chambers allowed hot gases to pass through the structure, and layers of shattered circular sheets remained on the floor. Surrey Archaeological Society has described this horizontal two-chamber arrangement for crown sheets as unique in England among excavated sites of its kind.
Window glass, vessels and medical equipment
Crown window glass formed a principal product. The maker blew a large vessel, opened it and spun it rapidly until centrifugal force created a thin circular sheet. A thickened centre marked the point where the glass remained attached to the iron pontil. Curved fragments and central pieces found during excavation allowed archaeologists to reconstruct the process.
The range of vessels was equally striking. Bottles, flasks, drinking glasses, dishes, small plates and hourglasses emerged from the excavated material. Solid linen smoothers were used to press and polish cloth. Urinals and other specialised forms linked glassmaking with medical examination and treatment.
Fragments of alembics, receivers, channels, tubes and spouts belonged to distilling equipment used in the preparation of medicines, perfumes and chemical substances. These objects required controlled shaping and carefully formed joints. They show that the craftsmen served specialised customers alongside the broader market for windows and domestic vessels.
Broken glass, known as cullet, returned to the furnace. Remelting reduced the quantity of fresh raw material and helped the batch fuse. Some coloured or decorated fragments found at Knightons may have arrived as cullet from other sources, while the forms and manufacturing waste identify a substantial range made within the clearing.
The Edward VI shilling
One small object gave the workshop an unusually precise date. Excavators found a silver shilling of Edward VI, dated 1550, among layers of shattered crown glass on the floor of the annealing furnace. Its position placed it within the working deposits of the building.
The British Museum identified the coin as a base-silver issue. It was in very good condition and belonged to a currency that was withdrawn in 1560. The coin therefore supports activity during the 1550s, the same period indicated by pottery, furnace sequence and scientific dating.
The route of the shilling into the furnace remains open to several possibilities. It could have fallen from a worker’s clothing, entered with a payment or been set aside after changes in its value. Its archaeological setting gives a date to the glasshouse, while the identity of its owner remains beyond the surviving evidence.
Continental skills and Henry Smyth
The design of the Knightons annealing furnace resembles French or Norman practice. Glassmaking knowledge moved through Europe with merchants and skilled workers, and the Weald became one of the English landscapes in which continental techniques were applied and adapted.
In April 1552 the London merchant Henry Smyth received a royal licence to bring foreign specialists to England to make broad or Normandy window glass. The licence belongs to the same decade as the principal activity at Knightons. Smyth also acquired connections within the wider Guildford and Godalming district.
The date, furnace form and regional connections make an association with Smyth’s enterprise a serious possibility. Surviving documents have yet to identify Knightons as one of his workshops, so the relationship remains a carefully framed hypothesis. The evidence firmly places Alfold within the wider transfer of technical knowledge that was reshaping English glass production.
John or Jean Carré and the later glasshouse
A named glassmaster enters Alfold’s story through the parish record. Francis William Cobb, the former Rector of Alfold who published the first sustained history of the village in 1935, recorded the burial of John or Jean Carré at “Awfolde” in May 1572. Local tradition remembered him as the last master of an Alfold glasshouse.
Cobb also associated a worn slab in St Nicholas’ churchyard with the glassmaker. Its inscription had disappeared, and the identification rested upon local tradition. Earlier Surrey antiquaries recorded memories of French glassworkers and their graves in the district, giving Carré a place within a broader story of continental craftsmen in the Weald.
Knightons appears to have been most active in the 1550s. The eastern glasshouse in Sidney Wood produced later material and offers another possible setting for glassmaking around Carré’s lifetime. The burial entry supplies a named participant in Alfold’s industrial community, while the excavated sites preserve the workplaces in which that community developed.
The woodland industry changes
Glass furnaces had limited working lives. Heat damaged their fabric, fuel demands altered the surrounding coppice and businesses responded to changes in labour, ownership and markets. At Knightons useful cullet, crown glass, a flask and crucible fragments remained when work ceased, preserving a detailed snapshot of the final production phases.
During the early seventeenth century the economics of English glassmaking changed. Coal-fired production developed from 1611, drawing important workshops towards places with access to mineral fuel and transport. A royal proclamation in 1615 restricted the use of wood for glass furnaces, increasing pressure on the forest industry.
The transition took place over time. The eastern Sidney Wood glasshouse has produced early seventeenth-century material of exceptionally fine forest glass, showing that skilled work continued within the wood after the principal phase at Knightons. The clearings later returned to trees, leaving burnt earth, furnace debris, clay pits and fragments beneath the woodland floor.
Maps, place-names and Surrey historians
The memory of glassmaking survived through maps and names. John Speed, the early seventeenth-century cartographer, marked a glasshouse west of “Awfold” on his map of Surrey, published in 1611. The symbol records an active or recently familiar industry within the parish landscape.
The name Glass House Fields continued to identify land associated with the furnaces. John Aubrey, the seventeenth-century Surrey antiquary, recorded traditions of French glassmakers in the area. Owen Manning and William Bray, the county historians whose multi-volume history of Surrey appeared in the early nineteenth century, described decayed glassmaking houses within the large wood carrying the Sidney name.
These records indicate more than one industrial location. Modern fieldwork distinguishes Knightons in the west from the eastern Sidney Wood glasshouse, also known through Glasshouse Copse. The broad symbol on Speed’s map and the later field-names preserve the industry at landscape scale, while archaeology supplies the precise working areas.
Cobb, Winbolt and the eastern site
Interest in the glassworks revived during the early twentieth century. Reverend Cobb examined the eastern site in 1923 while gathering evidence for his village history. He brought together parish tradition, John Speed’s map, Glass House Copse and the burial of Carré.
Samuel Edward Winbolt, an archaeologist and antiquary with a particular interest in Roman roads and Wealden industry, investigated the Sidney Wood glasshouse in 1930 and 1931. He described a rectangular working area and furnace remains and published the results in Wealden Glass in 1933. Later assessment dates much of the glass from this disturbed site to the early seventeenth century.
The eastern site produced forest glass of very fine quality. Its material extended Alfold’s chronology beyond Knightons and showed that Sidney Wood contained successive centres of production. Newspaper reports carried the discoveries to a wider public and encouraged further searching among the trees.
A wartime find and Felix Holling’s discovery
In 1943 J. B. Mawby, a Canadian sapper stationed in Britain, presented glass and pottery from Sidney Wood to Guildford Museum. The gift preserved finds made during wartime and kept the woodland industry within the museum’s archaeological collections.
The decisive discovery came in May 1965. Felix W. Holling, an assistant and museum archaeologist at Guildford Museum, recognised low mounds, burnt ground, glazed stones, crucible fragments and pieces of glass near the western edge of Sidney Wood. His trained reading of the surface identified another glasshouse site.
Holling informed George H. Kenyon, the specialist whose research established the framework for studying the glass industry of the Weald. The newly recognised site was named Knightons after nearby properties, distinguishing it from the eastern glasshouse already known in the wood.
Excavation restores the workshop
Surrey Archaeological Society began excavation in the autumn of 1965 and continued through a series of seasons under Eric S. Wood and Felix Holling. Wood, an archaeologist who had already investigated the medieval glasshouse at Blunden’s Wood, later published the full account in Surrey Archaeological Collections in 1982.
The excavation exposed furnaces, working floors, stores, clay pits, waste deposits and thousands of fragments. Each category of evidence contributed to the reconstruction of production: furnace architecture showed the control of heat, cullet demonstrated recycling, vessel fragments revealed the range of goods and the shilling fixed the workshop within the reign of Edward VI.
The Forestry Commission protected and presented the site, and later topographical and geophysical surveys examined both Knightons and the eastern glasshouse. Survey work in 2011 and 2012 mapped earthworks, structures, water management and concentrations of glassmaking waste, adding the wider industrial landscape to the excavated furnaces.
Sidney Wood and Alfold’s Tudor industry
Knightons now forms one of the most complete excavated glasshouse complexes in the Weald. The eastern site adds a later phase, and the two locations place Alfold within the development of English forest glass from the mid-sixteenth into the early seventeenth century.
The surviving evidence reaches from royal licences and county maps to a lost shilling, shattered window sheets, clay crucibles and fused furnace stone. Named researchers also form part of the story: Cobb and Winbolt renewed interest in the eastern glasshouse; Mawby preserved wartime finds; Holling recognised Knightons; Kenyon placed it within the regional industry; and Wood directed and published the excavation.
Sidney Wood remains a managed landscape in which trees, streams, tracks and clearings preserve the setting of Tudor production. Beneath the ground lie the physical traces of craftsmen whose windows, vessels and scientific equipment entered homes, churches, workshops and medical practice across a much wider market.
