IELTS Reading TFNG practice and gapfill (The History of Glass)

•  Early humans used a material called 1 obsidian to make the sharp points of their 2 spears.

Historians have discovered that a type of natural glass – obsidian – formed in places such as the mouth of a volcano as a result of the intense heat of an eruption melting sand – was first used as tips for spears.

•  4000 BC: 3 beads made of stone were covered in a coating of man-made glass.

Archaeologists have even found evidence of man-made glass which dates back to 4000 BC; this took the form of glazes used for coating stone beads. (glazes = coating)

•  First century BC: glass was coloured because of the 4 impurities in the material.

Glass blowing became the most common way to make glass containers from the first century BC. The glass made during this time was highly coloured due to the impurities of the raw material.

•  Until 476 AD: Only the 5 Romans knew how to make glass.

The secret of glass making was taken across Europe by the Romans during this century. However, they guarded the skills and technology required to make glass very closely, and it was not until their empire collapsed in 476 AD that glass-making knowledge became widespread throughout Europe and the Middle East.

•  From 10th century: Venetians became famous for making bottles out of glass. (There’s no gap for this sentence – use it to help you follow the order of the gaps in the text)

From the 10th century onwards, the Venetians gained a reputation for technical skill and artistic ability in the making of glass bottles, and many of the city’s craftsmen left Italy to set up glassworks throughout Europe.

•  17th century: George Ravenscroft developed a process using 6 lead to avoid the occurrence of 7 clouding in blown glass.

A major milestone in the history of glass occurred with the invention of lead crystal glass by the English glass manufacturer George Ravenscroft (1632 – 1683). 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.

•  Mid-19th century: British glass production developed after changes to laws concerning 8 taxes.

In Britain, the modern glass industry only really started to develop after the repeal of the Excise Act in 1845. Before that time, heavy taxes had been placed on the amount of glass melted in a glasshouse, and were levied continuously from 1745 to 1845.