History of Glassworks
Traditional Furnaces and Glass Blowing
From as far back as the 9th century, the first glassworks were founded in Bohemia.
With the creation of the Roman Empire there was a distinct change in the way glass was used. The incredibly important discovery of glassblowing happened somewhere around the year 50 BC. With this discovery, vessels could be made by blowing the glass as opposed to forming them around a core, which meant that the possible shapes of vessels seemed infinite. The Roman Empire was made up of France, Spain, Portugal, England, Belgium, Switzerland, North Africa, regions of the Netherlands, Germany and Austria. It was during the reign of the Roman Empire, that through the discovery of glass blowing that glass became much more of a household object. Blowing vessels was more efficient than core-forming, and so glass became available to the wider population. Moulds were used to help shape the glass together with for the purpose of leaving imprints on the walls of a vessel. Glass could be blown into a mould that had cut designs in it, and the cuts in the mould would then leave imprints on the glass. After the hot glass was removed from the mould, the glassblower could continue to work with it. Glass production was not just confined to common use objects, glassblowers were also making some of the most elaborate glass objects that were not possible previously. To enhance aesthetics the beauty of the glass was augmented with inlays of gold and brilliant colours. One of the uses of these glorious vessels was to hold rare and expensive ointments together with perfumes and cosmetics. As technology advanced enamelling techniques were also enhancing, and glass was being used for decoration to inlay ceilings.
Free Glass Blowing as a technique, whereby the blower handles a stand alone pipe, has held a pre-eminent position in glass forming ever since its evolution in the middle of the first century B.C. right through until the late nineteenth century and even today it is still widely used. The technique of free blowing involves the blowing of air into a molten portion of glass at the end of the blowpipe using short puffs. This process has the effect of forming an elastic skin on the inside of the glass blob which matches the exterior, which is caused as it cools after being removed from the furnace. The glassworker can then rapidly inflate the molten glass to form a coherent blob and then work it into a desired shape.
The Toledo Museum of Art did attempt to reconstruct the ancient free-blowing art by using clay blowpipes.
The result has proved that short clay blowpipes of about 30-60 cm enable free blowing to be performed most successfully, because they are simple to handle, easy to manipulate and can be re-used multiple times. Consequently, skilled workers are able to shape most vessel forms by rotating the pipe, using a swinging action and monitoring the temperature of the piece during blowing. These craftsmen can produce a great variety of glass objects, ranging from drinking glasses to flat window glass. It was 500 years ago that Bohemian glassmaking made further advances in the former Kingdom of Bohemia, in which skilled craftsmen discovered ways of shaping glass into aesthetically pleasing forms. The skilled craftsmen then perfected the art of glass blowing producing the naturally shaped base forms that will then be hand cut and decorated to create the necessary chandeliers parts. It was by the beginning of the 17th century that Bohemian glassmakers started to manufacture glass which more closely resembled pure natural crystal. < For that reason it was subsequently named "Bohemian crystal" and became a highly prized commodity.
Here we can see a modern day blown glass item using very similar techniques to those in the past.