Glass blowing
Stained Glass Windows: Managing Environmental Deterioration, published by Historic England in 2020, suggests that glass blowing is a: ‘Glass-forming technique, probably developed in Babylonia and the Middle East by the 1st century BC. Molten glass is gathered into a ball on the end of a hollow pipe, and rolled on an iron former to roughly shape it and to slightly cool the surface. Then the pipe is used to blow air into the glass and form it into a bubble. By repeated blowing, shaping and reheating, the glass can be formed in many ways.’
Archaeological Evidence for Glassworking, Guidelines for Recovering, Analysing and Interpreting Evidence, published by Historic England in 2018, defines a blowing iron as: ‘A long iron tube that was dipped into the molten glass to collect a gather for subsequent inflating and shaping.’
It defines optic blowing as a process in which: 'A gather of glass is blown into a mould with a pattern on the inner surface, which transfers to the glass. Continued free blowing results in movement and distortion of the pattern.'
And overblow as: 'A by-product of mould blowing, referring to the glass that remains outside the mould, which is removed and recycled.'
It defines paraison as: 'The partially inflated gather of glass at the end of the blowing iron.'
And paraison end as: 'A marble-shaped blob of glass pinched from the end of the gather during the blowing of particular forms, such as the bowls of goblets.'
[edit] Related articles on Designing Buildings Wiki
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
CIAT responds to Climate Change Committee report
An urgent wake-up call for both government and the built environment.
Construction Management, 24 June
FMB pilot aims to build pipeline of site-ready tradespeople.
A quick introduction.
CLC publishes Mental Health Joint Code of Practice.
A quick introduction to its uses and risks.
Construction Management, 17 June
Government rolls out digital planning tool to all local authorities.
Your views needed - a strategy for the professions, trades and occupations.
Confronting competency, codes, capacity and costs.
The hidden risk in modern construction supply chains.
Construction Management, 10 June
24 months to 14: CITB launches accelerated apprenticeships.
Bridging the gap between clients and contractors
Concerns remain around contractor quality, capability, and delivery.
















