Stratford Guild REVIEW of 11 June talk - 'The Wonderful World of Glass'

“The Wonderful World of Glass” - Dr Francis Burroughs

Our speaker gave us a fascinating talk which traced the origins of glass-making from 3000BCE up to the present day. It was informative, interesting and……amusing. Francis has a very extensive knowledge of his subject gained through long involvement with the manufacture of glass at his company Bristol Blue Glass, and a consuming passion for the craft.

Francis is an acknowledged expert, and has often been asked to provide items for television programmes or give his expert advice. He brought along some glass exhibits from his amazing private collection and passed them around the audience for examination.

We were very privileged (not to mention nervous) to be able to handle such unique and exquisite examples of glasswork, some of which were thousands of years old and worth a fortune. We were taken on a journey through the centuries of glass making and then brought up to date through the inclusion of some very beautiful items manufactured in Bristol.

Natural glass – obsidian – was formed from sand and other minerals melting together, for example from the intense heat of a volcano melting the sand.

The first glass manufactured by humans can be dated back to around 3100BCE in the area of Syria, Mesopotamia or Egypt. Long thin tube beads were very common and often used for trading. Examples have been found in many burial sites, including Avebury and Stonehenge.

Some time around 1500BCE glass making had progressed to making small vessels using clay moulds, then molten glass was drizzled around the outside of the mould. When cold, the clay was broken out from the middle. This technique was used up to 100BCE.

About 50BCE, the Phoenicians invented glass blowing from molten blobs of glass to which a tube was attached to blow air through, enabling the glass to be shaped. However, glass at this time was highly coloured due to the impurities of the raw material. It was not until around the first century CE that colourless glass was produced and then coloured by the addition of colouring materials. Thus Rome became the centre of glass production, trading across Europe and to Britain. However, the skills and technology required to make glass were closely guarded by the Romans and it was not until the Roman Empire disintegrated that these skills spread.

Glass makers from the Middle East travelled the Silk Road to Venice where, in 1264, all glass making was established on the Venetian island of Murano and the technical skills and artistic ability were kept a trade secret.

Meanwhile, back in Britain, from 13thC there was a thriving glass industry in Sussex because of the sandy soil and the abundance of trees for the furnaces. Workers moved from Venice to Sussex. In 1615 a law made it illegal to blow glass in Sussex, to save the trees for shipbuilding. Glass making moved to other sandy areas where coal came into ports from Newcastle.

A major milestone in the history of glass occurred with the invention of lead crystal glass by George Ravenscroft (c.1700) which took him 15 years to develop. He attempted to counter the effect of clouding that sometimes occurred in blown glass by introducing lead to the raw materials used in the process. He produced high quality 38% lead crystal. It was also possible to engrave patterns on this type of glass.

By the18thC Bristol was the second largest city in the country by population. Bristol docks received trade from Africa, India, New Zealand, Americas etc. Cobalt from Saxony also came in to Bristol for creating blue glass tiles and blue glass ware.

One famous maker was Isaac Jacobs, son of Lazarus who was a glass maker from Frankfurt. It is known that in 1805 ‘Royalty’ bought 8 decanter stands made by him, which enabled him to put up his prices as he could advertise “made for Royalty” on his letterheads. He also started to sign his glassware. Dr Francis owns one of these signed decanter stands and was in fact approached by ‘Royalty’ to purchase his, as one of their original 8 had been broken. He declined. Eventually, various wars stopped the trading of cobalt from Saxony.

Around 1916, Graal glass was manufactured in Sweden. The technique was an exclusive speciality, which involved several layers of different shades of glass, with patterns being cut on the inside, then being heated for 48 hours to near melting point and blown, taking 5 or 6 hours, to form a larger round bowl. It was then dipped in clear glass all over. Cooling back down taking 72 hours.

From 1850 to 1950, 97% of the world's glass was made in Britain at Stourbridge, where thousands were employed in the industry. By this time any colour of glass was available due to the development of the chemical industry.

The audience were enthralled throughout the talk, after which Francis happily answered a number of questions.

                                                                                          Barbara Mayall.