Unit 6 history of glassmaking lead-in

Task 1. Use your general knowledge and define the sentences containing the appropriate characteristics of glass. Note that two of five sentences are given by mistake.

1. Glass is a substance of acidic nature, in the sense that it contains a predominating proportion of silica.

2. Glasses have the mechanical rigidity of crystals, but the random disordered arrangement of molecules that characterizes liquids.

3. Glass has the ability to refract, reflect, and transmit light following geometrical optics, without scattering it.

4. Glass is a solid material that is typically hard, opaque, shiny, and features good electrical and thermal conductivity.

5. The ability of glass to sustain large deformations with relatively little damage or permanent set makes it ideal for many applications.

Task 2. Read and memorize the following words and phrases for better text comprehension. Then choose the words from the vocabulary list to complete the sentences below.

disordered arrangement	хаотичне розташування
impurities	домішки, включення
glassmaker	майстер-склодув
core forming	нашарування
clay	глина
сasting	лиття (скла)
artist	гравірувальник
to carve	вирізати, гравірувати
glassblowing	видування скла
blowpipe	склодувна трубка
to melt	плавити

1. ____is a heavy, sticky material from the earth that is made into different shapes and that becomes hard when it is baked or dried.

2. There are many different jobs for a____, from working in industrial settings to creating beautiful glass beads or decorative pieces as a hobby.

3. It's easy to____ brass and other metals like silver, gold, aluminum, copper, bronze and tin.

4. Before attempting to____ wood, it's important to know that the softer wood is, the easier it's going to be to____.

5. ____are substances inside a confined amount ofliquid, gas, or solid, which differ from the chemical composition of the material or compound.

6. ____ is a tube through which a stream of air or gas is forced into a flame to concentrate and increase its heating action.

Task 3. Choose the right option to complete the following statements. Then read the text of Task 4 to check your answers.

1. Glass has always been found in ……, but the first glass created by man can be dated to about 4,000 years ago.
a) environment	b) nature	c) sand
2. The techniques used to shape ……, casting and core forming, remained the same for more than a thousand years.
a) glass	b) clay	c) metal
3. The glassmaker would make glass smooth and symmetrical by twirling and moving the ……, and then reheat it and blow into a bubble by breathing.
a) stick	b) blowpipe	c) rod
4. Glass can be …… by the addition of metallic salts, and can also be painted.
a) cooled	b) coloured	c) heated
5. The recipe for making glass is still the same today, requiring little except ……, soda ash and heat.
a) copper	b) silica	c) liquid
6. As the glass cools, the atoms become locked in a …… state like a liquid before they can form into the perfect crystal arrangement of a solid.
a) ordered	b) disordered	c) structured