Welcome to the Semi-official web page on how people used to make glass



This page is my project for the RAP II program at Kirksville Junior High School. In this class we are sudying ancient civilizations and are required to research a topic and present it somehow. I decided to research how people make glass and to present it on this page
Well, first you should probably know the history of glass before I tell you how people make it. Glass was first created naturally as obsidian. Glass was also formed when lightning struck sand and formed a glass rod. The first use of glass in civilization was a glaze over ceramics around 3000 B.C. The first glass vessels were produced in Egypt and Mesopatamia around 1500 B.C. Early glass making took a lot of time and was extremely costly, so glass became a valuable comodity owned only by the rich Merchants learnde that glass vessels preserved several perishable items such as wines, honey, and oils.

Around 30 B.C. the blowpipe was invented by some unknown person, probably somewhere along the Mediterranean. This invention made it much cheaper and easier to manufacture glass and took off the luxury list. Then the glass industry became important for all of the countries under Roman rule and the First Golden Age Of Glass began. Artisans started creating transparent glass. They knew how to build layers of different colors of glass and then cut out high relief designs The Portland vase is a good example of this art and is one the most valuable glass objects in the world, having been made at the beginning of the Christian Era.

Not much is known about the glass industry between the decline of the roman Empire and the 1200's. However, glass manufacturing had been established in Venice by the time of the Crusades. By 1291 elaborate system of guilds of glass workers had been set up. Equipment was transfered to the Venetian island of Murano. It was here that the Second Golden Age Of Glass began. It was on the island of Murano where artisans perfected clear glass in a style called Cristallo. This glass could be blown to extreme thinnessin almost any shape. Cristallo glass was made into lacework patterns in jars, cups, gobletsand vases. IT was in the 11 and 1200's that stained glass making reached its height in Europe. In the 14 and 1500's glass making had spread noth to countries such as Germany. Northern forms of glass were much heavier and less clear than Cristallo. In the late 1500's many Venetians move north in order to make a better living and several established glass factories that made glass in Venetian style. In Bohemia a new kind of glass was developed that could easily be decorated with copper-wheel engraving.

Glass making became important in England during the reign of Queen Elizabeth I. By 1575 English glass makers were making Venetian style glass. However in 1674 a man by the name of George Ravenscroft patened a type of glass that changed the normal ingredients of the glass. This glass known as lead glass contained large amounts of lead oxide. This was suitable for making optical intruments such as telescopes and field glasses. This allowed the English glass industry to to prosper.

The first factory in the United States was a glass factory that was built at Jamestown, Virginia in 1608. This industry failed because of a famine that killed many of the colonists. Jamestown colonists later tried to create a glass industry again in 1621 but failed because of an Indian Massacre in 1622, and lack of workers. The glass industry has now been esatblished since 1739. Caspar Wistar built a glass making plant in Salem County New Jersey.

But enough of how the industry got started lets get down to how glass is made now and also how it used to be made. Core moulding was the easiest method of producing glass this was done by starting with a core of clay and dung. This core was fixed to a metal rod, and given the shape that the vessel would end up looking like and then it was dipped into molten glass. it was constantly being reheated and then smoothed on a stone by rolling it. When it cooled the core was taken out and you had yourself a glass vessel that you could do what ever you wanted to with.