Glass History: Middle Ages
Task: You are working as a trainee at the glassmuseum in Rheinbach. The head of the press department has begged you and your colleagues to write a short overview on the history of glass for the catalogue of the permanent exhibition. Use the following text as a database and write a summary on glass in the middle ages. Put your text in the Glass Classroom.
If you don't know exactly how to summarize, open this worksheet: summary (beginners)
The early Middle Ages
Archaeological
excavations on the island of Torcello near Venice, Italy, have unearthed objects
from the late 7th and early 8th centuries which bear witness to the transition
from ancient to early Middle Ages production of glass. Towards the year 1000,
a significant change in European glassmaking techniques took place. Because
of the difficulties in importing raw materials, soda glass was gradually replaced
by glass made using the potash obtained from the burning of trees. At this
point, glass made north of the Alps began to differ from glass made in the
Mediterranean area, with Italy, for example, sticking to soda ash as its dominant
raw material.
Sheet glass skills
The 11th century also saw the development by German glass craftsmen of a technique - then further developed by Venetian craftsmen in the 13th century - for the production of glass sheets. By blowing a hollow glass sphere and swinging it vertically, gravity would pull the glass into a cylindrical "pod". While still hot, the ends of the pod were cut off and the resulting cylinder cut lengthways and laid flat. Other types of sheet glass included crown glass, relatively common across western Europe. With this technique, a glass ball was blown and then opened outwards on the opposite side to the pipe. Spinning the semi-molten ball then caused it to flatten and increase in size, but only up to a limited diameter. The panes thus created would then be joined with lead strips and pieced together to create windows. Glazing remained, however, a great luxury up to the late Middle Ages, with royal palaces and churches the most likely buildings to have glass windows. Stained glass windows reached their peak as the Middle Ages drew to a close, with an increasing number of public buildings, inns and the homes of the wealthy.
Italian centre of glassart: Venice
In the Middle Ages, the Italian city of Venice assumed its role as the glassmaking centre of the western world. The Venetian merchant fleet ruled the Mediterranean waves and helped supply Venice's glass craftsmen with the technical know-how of their counterparts in Syria, and with the artistic influence of Islam. The importance of the glass industry in Venice can be seen not only in the number of craftsmen at work there (more than 8,000 at one point). A 1271 ordinance, a type of glass sector statute, laid down certain protectionist measures such as a ban on imports of foreign glass and a ban on foreign glassmakers who wished to work in Venice: non-Venetian craftsmen were themselves clearly sufficiently skilled to pose a threat. Until the end of the 13th century, most glassmaking in Venice took place in the city itself. However, the frequent fires caused by the furnaces led the city authorities, in 1291, to order the transfer of glassmaking to the island of Murano. The measure also made it easier for the city to keep an eye on what was one of its main attractions, ensuring that no glassmaking skills or secrets were exported.
In the 14th century, another important Italian glassmaking industry developed at Altare, near Genoa. Its importance lies largely in the fact that it was not subject to the strict statutes of Venice as regards the exporting of glass working skills. Thus, during the 16th century, craftsmen from Altare helped extend the new styles and techniques of Italian glass to other parts of Europe, particularly France.In the second half of the 15th century, the craftsmen of Murano started using quartz sand and potash made from sea plants to produce particularly pure crystal. By the end of the 16th century, 3.000 of the island's 7.000 inhabitants were involved in some way in the glassmaking industry.
note: This is an abbreviated and simplified version of the glass history on http://www.glassonline.com
