Glassmaking
Glass making eventually returned to Britain with the re-build of Canterbury Cathedral in 1174, after a fire had destroyed the older Norman Cathedral, The glass was inspired by the building of Chartres Cathedral in France just prior to this, whose Glass makers were imported from the Middle East, as there were no persons with the required skills in Europe at that time. So the original glass makers of Chartres were Muslims and this is evident in some of the windows there.
The Glass maker who came to make the glass was called Lawrence Le Viteraux (The Glass), he set up in Kent. The glass being made was very rough and ready during the Middle Ages in Britain and a lot was still being imported from the Continent. There was a bit of a scorched earth policy for the glass makers as they made their wares in the ~Forest or in medieval time the Weald. Welding, the modern word means to join metal together using heat, the origination of the word comes from the medieval word for forest as all the work was done there. A lot of deforestation occurred during this period, which lasted right until James 1st was on the throne and he decreed that 'No Glass can be made using wood as fuel, save there being a single tree left standing upon this isle'. Therefore a new fuel had to be utilised and coal was the obvious choice.
Aside – Gaffer, is the medieval word for Glass maker – 'Glasser' the F & S were not defined at this time.
Coal was a difficult fuel to use as it does not burn clean like wood does so the furnaces had to be completely redesigned to allow for this new fuel. They came up with a Glass cone with covered pots to keep the glass clean. These edifices became landmarks in the the glass making centres around the country.
There is little known about the history of glassmaking in Britain during the next one thousand years, although we do know that glassmaking survived as a trade. In early 2004, a Saxon burial chamber was unearthed in Prittlewell in Essex and amongst the artefacts buried with the early Saxon was a beautifully preserved and intact blue glass bowl.
Glassmaking underwent a renaissance in the and 14th centuries. The revival began in Venice (a city which is still thought of as the glass capital of the world) and spread throughout Northern Europe. It would have been very likely that all towns of any size would have had their own glassmaker.
http://www.bristol-glass.co.uk/history.html
https://www.google.ca/search?tbm=bks&hl=en&q=medieval+production+glass+salicornia
https://www.researchgate.net/figure/a-Depiction-of-a-medieval-glass-furnace-showing-the-quarrying-of-sand-in-a-landscape_fig3_272524095
https://en.wikipedia.org/wiki/Glasswort
https://en.wikipedia.org/wiki/Salicornia_europaea
https://en.wikipedia.org/wiki/Salicornia
https://en.wikipedia.org/wiki/Salt_marsh
17th century glassmaker and alchemist Antonio Neri handled very dangerous materials on a daily basis. He used strong acids, which if splattered could easily burn flesh, or cause blindness. He handled poisonous compounds containing arsenic, mercury and lead. If ingested, or inhaled as fumes these materials caused progressive, irreversible damage to internal organs and especially to the nervous system. There is no question that Neri did take chances with his health, but he was not naive. He knew very well many of the potential dangers and others he could well imagine.
