The name of Nailsea is associated all over the world, with the glass to which it has given its name. Much has been written about Nailsea glass, but the newcomer may be confused by the utterly different styles and products described as "Nailsea", and their relationship to the Nailsea glassworks.
First, some straightforward facts. The glassworks at Nailsea was established in 1788 at the edge of Nailsea Heath by John Lucas. Lucas was an established entrepreneur with business interests in other glassworks as well as brewing, but he seems to have concentrated on the Nailsea works. There seems no doubt that he hoped to profit from establishing his new works close to a ready supply of coal: glassmaking requires large amounts of fuel to fire the furnaces for the different stages of manufacture - melting, working and annealing. Lucas established partnerships with local mine owners, as well as industrialists who could provide capital and experience in helping to manage the operation. Nailsea was also close to sources of the bulk ingredients needed for glass: both sand and limestone were probably taken from the Failand ridge, at least in the early years of the works. (Sand of higher purity was brought from the south in later years). The glassworks remained in operation for 85 years and its presence played a major part in shaping Nailsea up to the present day.
During most of the time when the Nailsea glassworks was operating there was an excise duty on glass, which was regarded as a luxury material. However, different grades of glass attracted different levels of duty - higher for the clearest and most brilliant grades used for fancy goods, while the dark glass used for bottles was correspondingly less highly taxed. In general, the system of duty on glass became more complex as time went on, while the rates of duty rose steadily. These increases were partly offset by the introduction of allowances for the considerable quantities of waste glass produced in manufacturing operations, and by a gradual change from taxation of the raw materials of manufacture, to a charge on the finished goods. An excise officer would be in regular or constant attendance at the works until abolition of the duty on glass in 1845, and can be identified in a range of the records related to Nailsea.
Glass is based on a mixture of silica (sand) and lime. However, a glass based only on those materials requires extremely high temperatures for its preparation and is very difficult to work, so other materials are always added. Of these, soda and potash are the most basic. During the time of the Nailsea works, both were obtained from vegetable sources; potash was obtained from the ash of hard woods, and soda from burning salt tolerant plants like samphire and its relatives (also known as glasswort) or seaweed. After the mid-1820s, soda also began to be produced in England in volume from salt by the industrial LeBlanc process. The relative proportions of materials used in the melt determined the characteristics of the glass - its brightness, hardness and durability. They also determined the suitability of the glass for working by different processes, and the amount of tax to be paid. The colour of glass was affected by the quality of the raw materials. Cheap sand, high in iron would give a dark coloured glass while white sand could yield glass with only a light green tint. Other additives could be used to improve the product, and some of the costliest were used to provide deep red, green and blue colours. This was certainly done at Nailsea, but probably mainly toward the later years of the factory's life. Two recipes for glass melts dating from Nailsea in 1836, refer to the use of Glauber's salt - sodium sulphate - rather than (or in addition to) soda.
In the earliest days of glassmaking at Nailsea, bottle making seems to have been a major part of the output. This is reasonable in a new works; the workmen required less skill than for sheet glass making, and the formulation and melting of the glass for bottles was more forgiving. Bottle making may possibly have had some connection with Lucas' brewing interests. Later in the life of the works, production seems to have concentrated entirely on window glass, manufactured by the various processes developed and improved through the 18th and 19th centuries. Glass was first formed by melting the ingredients in very large fireclay pots - around 5 feet tall and nearly 6 feet across. This founding stage would take 30 hours or so. Crown glass was formed by blowing a bulb of glass, and opening the end of the globe. The glass was then spun in a furnace to flatten and extend it into a large disk (several feet across!), which was then cooled and cut to shape for glazing. Because the glass hardened without contact to another surface, a smooth high quality product could be obtained. The other basic process involved blowing a glass bulb which was cut open and flattened onto a surface. There were many variations on this theme: the glass could be blown initially into a cone, bulb or long cylinder. It could be flattened onto sand or smooth metal. All of these processes gave window glass which was inferior to crown glass. For the highest quality product, the surfaces of cylinder glass could be polished - a laborious and expensive process.
The ornamental and whimsical pieces most often seen described as "Nailsea glass" today, have little in common with this staple production. They are typically attributed as friggers or end-of-day pieces made by the glassworkers for sale, from the residue of the batch of glass when production was complete. The most typical pieces include glass walking sticks, rolling pins, and ornate items such as lamps and pipes. Dark glass domestic items such as jugs and tankards may have been manufactured at Nailsea alongside bottles. Sadly it is usually impossible to identify the glassworks at which any of these items was made, unless there is a clear history trail. Similar items seem to originate from many glassworks, and many items offered as "Nailsea" clearly date from a period when the Nailsea works was long closed. The Nailsea designation today refers to a range of styles of glass, rather than to any particular place of manufacture. Nailsea glass can be beautiful and costly, but unless there is compelling evidence, it is probably best to assume that any particular piece has no real connection to the Nailsea works.