Teachers' resource: Glass
The Victoria and Albert Museum's sparkling and colourful Glass galleries (Rooms 129 and 131) offer students of all ages an exciting learning environment.
This resource for primary and secondary school teachers aims to show how the gallery can be used to support the Art & Design, Design & Technology and History areas of the curriculum. The activities are suitable for all key stages.
How the Glass gallery is organised
The main section of the Glass gallery presents a thematic history of glass from Ancient Egypt to the present. Each case in the gallery deals with a theme, technique, style or period. Within each case, numbered bays contain groups of objects relating to different aspects of the main theme.
The mezzanine floor, up a staircase designed by contemporary glass artist Danny Lane, contains the Glass Study Collection, which is arranged chronologically.
Each object has a number on a small perspex label. These numbers are listed at the bottom of the case with a brief description of the object. To find out more, go to the computer terminals in the gallery, which have information about each object. They also give access to a multi-media program, The Story of Glass, which includes a world history of glass, its makers and its uses, combined with footage of glass-making, as well as more technical information on materials and methods.
Three materials are required to make glass:
- An alkaline flux to lower the melting point and enable the glass to be worked at a lower temperature
- A stabiliser, usually lime, to make the glass water-resistant
The combination of these materials is called the 'batch'. The batch is heated to about 1500oC, when it becomes liquid and can be formed into the desired shape. Glass can only be worked when it is hot, so it must be re-heated frequently. On completion it must be cooled slowly in a kiln to avoid cracking. Even when it has cooled, glass is still technically a liquid because it has no rigid crystalline structure.
The most common technique for shaping glass is blowing. A piece of molten glass is placed on the end of a blowpipe and expanded by blowing air into the pipe. Glass produced in this way can be free-blown and then worked by hand, or blown into a mould.
Before the invention of glass-blowing around 50 BC, glass vessels were made by fixing a core of animal dung and clay onto the end of a metal rod and then dipping it into a pot containing the batch. After the glass had cooled, the rod and core were removed.
The sand used to make glass often contains natural impurities of iron, which gives the glass a green tint. To make colourless glass, either very pure sand must be used or the green must be neutralised by adding its complementary colour in the spectrum, a reddish purple. This comes in the form of manganese, but if too much manganese is added the glass will turn pink.
Glass is coloured with metal oxides:
- Copper or cobalt for blue
- A combination of iron and copper for green
- Gold for ruby red
- Uranium for a yellowy green
- Iron for yellow
Manganese for purple and brown
The addition of lead oxide makes a glass that is clear, heavy and brilliant. Called lead crystal, it can be cut with a rotating wheel made of stone, wood or metal, then polished.
Engraving glass with a small grinding wheel produces a matt surface, as does sand-blasting and etching it with hydrofluoric acid. To create a shiny surface, the glass can either be polished by hand when cold, or returned to the kiln to melt away surface marks. The semi-opaque, matt quality of Ancient Egyptian and pre-Roman glass came from the use of impure materials. Later glassmakers deliberately re-created the same effects.
The frosted texture of 'ice glass' is made by plunging the glass bubble attached to the blowpipe into cold water, then re-heating and blowing it. A similar texture is caused accidentally by crizzling. This is a glass 'sickness' in which the structure of glass is gradually destroyed by moisture in the atmosphere. An imbalance of ingredients in the batch makes glass prone to crizzling.
Opalescent glass is translucent and white with a greyish or bluish tint. It is made cloudy and semi-opaque by adding materials like bone ash to the batch.
Mirrors are made by backing the glass with tin, mercury or an amalgam of metals.
Below are some projects that you might like to study with your students:
A Victorian table setting
The invention of press moulding in America in the 1820s enabled manufacturers to reproduce complex designs in huge quantities. In press moulding, a blob of molten glass is placed in a metal mould and pressed by a metal plunger, which pushes it against the inside of the mould.
The wide availability of glass meant that the growing middle classes were able to deck their tables with an impressive range of items. To suggest wealth, propriety and regard for the rules of etiquette, each piece had a special function . Examples of glass made by press moulding can be seen in the cases Glass for the Million and Techniques.
Before your visit
Mrs Beeton provides a great deal of information about the glass used on the Victorian dinner table. For the main part of the dinner (that is, up to the sweet course), the book recommends that each place setting be laid as in the diagram below. A water carafe or jug should be placed at each corner of the table and a salt cellar between every two people. There might be a large flower vase as a centrepiece, along with a couple of smaller ones and possibly a small specimen tube for a single bloom at each place setting.
Fruit dishes were sometimes put on the table, but normally the sweet course would be left on the sideboard. Dessert was eaten from plates rather than bowls, with the exception of custards and jelly, for which there were special glasses. Ices (including ice creams and sorbets) were eaten from plates and finger bowls were brought to the table when the sweets were served.
Your students could list all the glassware that would have been used during the dinner. Their list might include: sherry glasses, champagne glasses, wine glasses, water tumblers, water jugs, a centrepiece flower vase, smaller flower vases, salt cellars, dessert plates, ice plates, fruit dishes, finger bowls and sugar bowls.
In the museum
Art and Invention
Glass for the Million
The Study Collection (particularly Bay 79)
Your students should draw the items needed to lay the table for all the courses before the sweets. Where appropriate, their drawings could be in colour. You may wish to divide your class into small groups and give each group a list of objects to find.
If there is time, students could draw some of the items that would have been used for dessert, such as dessert plates, ice plates, fruit dishes, finger bowls and sugar bowls.
Back at school
For a Victorian dinner table of this kind, the glassware would usually be a matching set. You will not be able to do this, but students should be made aware of the inaccuracy. Alternatively, you could photocopy the drawings to make sets of each type.
Students could conclude the project by designing menu cards or drawing flowers to add to the vases.
A glass painting project gives students an opportunity to actually work with glass. They can use a variety of paints. Specialist glass paints or enamels give the most permanent finish, but they sometimes have to be fired in a kiln. Younger students will find it easier to use acrylics or poster paints mixed with PVA glue. These can later be varnished to make them more water-resistant.
Many different ways of adding decoration to cold glass can be seen in the gallery. In enamelling, a paste consisting of powdered glass and metallic oxides is mixed with an oily medium and painted onto the glass. The object is then fired at a temperature just high enough to melt the enamel paste and soften the glass surface so they fuse together. Look out for examples of Islamic, Venetian and Bohemian enamelled glass in the gallery.
Gilded decoration is also added when the glass is cold, but it is not always fired. Gold in the form of leaf, paint or powder is applied to the surface, sometimes with a fixing agent such as gum arabic. Look for examples of gilding in Bay 20 and in the New Glass case near the entrance to the gallery.
Glass can also be painted with artists' paints, like the vase Snakes in Love (9813) by Ulrica Hydman-Vallien, in the large display case along the wall by the gallery entrance.
Students could take their decorative theme from another school project or from the Glass gallery itself. Natural forms, heraldry and the human form are subjects that are well-represented.
At the V&A
Different types of glass can be bought cheaply from charity shops, markets, glaziers or department stores. For primary school students you could use jam jars, which are sturdy, or you may prefer to substitute sheets of acrylic or clear plastic beakers. Acetate and acrylic sheets can be engraved with a sharp point and/or painted. You can make a pattern by painting over engraved lines and then wiping the surface to leave paint in the grooves. This technique also works using non-permanent OHP pens instead of paint. Glass paperweights with a blank base, on which a decoration can be stuck or painted, are available from some craft shops.
Students should practise glass-painting techniques before embarking on their final piece. The paint or enamel must be built up slowly, or it will run. Some manufacturers suggest making an outline first to stop this, so any instructions should be followed carefully.
Before painting, students should mark their designs out on the surface of the glass using OHP pens or chinagraph pencils. Very young students might find it easier to paint on a flat surface, whereas older ones can try working in three dimensions.
Glass can be transparent, opaque, reflective, matt or shiny. This project encourages students to explore these qualities in other media by setting them the task of making a box with a light source inside it and windows of different materials. The task could be done simply in primary school or made more complex for Key Stage 4 and 5 students.
At the V&A
In the gallery, students could make drawings and take photographs that concentrate on the qualities of transparency, opacity and reflection. To supplement their drawings, they could include other materials, such as tissue paper, tracing paper, blank OHP (overhead projector) sheets, acetate or tin foil. Students should attach samples of materials that most resemble the appearance of the glass objects they are looking at. Ask them to record small sections of pattern, texture or overlapping shapes. Viewfinders would help them select areas to draw.
Back at school
To make the light box, cut holes for the windows in four sides of a cardboard box (such as a shoebox), leaving a margin of 2-3 centimetres. Using card frames slightly larger than the holes, make windows of acrylic, acetate, polythene, varnished tissue paper, greaseproof paper or photographic negatives, all of which share some of the characteristics of glass . Add pattern and texture by painting and drawing on these materials. Then stick the windows inside the box with masking tape.
By placing a light source, like a torch or cycle light, inside the box you will see that the different materials and textures of the windows produce different qualities of light. A single torch will provide different levels of light for each window, but more than one torch can give directional lighting to each window. Darkening the room will enhance the effect. Students could construct their own light source using a battery, bulb holder and bulb, with a switch on the outside. This would tie in with Science and Technology at Key Stages 1 and 2. Take care not to overheat the box.
Students could either create their own individual box, or collaborate on a box by making a window each. Older students may want to experiment with reflective surfaces inside a larger box.
As an alternative to the light box, students could construct small frames of different shapes and make mobiles from them to hang by the classroom window.
For this project, students design a perfume or aftershave bottle, along with its ornamental stopper, for a 'client' of their own choosing, such as an haute-couture fashion house, a sports company or a clothing retailer. They also prepare a design brief for the project.
At the V&A
The Glass gallery has a fine collection of perfume bottles from different cultures and ages. Students might look at these initially, but their main task in the gallery is to draw other types of container that they can adapt for their designs. They should also look for shapes that would make good stoppers.
The cases New Glass, Presents from the Glasshouse and Late Islamic Glass are particularly relevant. The vase by Michael Glancy (9840), in the large case along the wall by the entrance to the gallery, is an example of an object that could be reinterpreted as a stopper.
To record objects in the gallery, students could use tissue paper collage, pastels or a combination of the two techniques. While they are in the gallery, they should make a note of the different types of glass and glass decoration, such as cut glass, enamel decoration, coloured glass, blown glass, and etched, pressed and engraved glass.
Back at School
In the role of client, students should prepare a design brief for the bottle. It should include the intended market and the message that the design, brand and packaging should communicate to the buyer.
From the drawings they made in the gallery, students could try a number of designs of bottles with different stoppers. They could experiment with scale (big bottle/small stopper; small bottle/big stopper) or make a series of designs for a 'collection'. Students could draw their designs in versions that use different techniques of shaping and decorating glass.
At the end of the project, students could present or 'market' their products, including the brief, working drawings and a mock-up of their final designs. Students should state the methods by which their bottles will be manufactured.
This project looks at the patterns of the stems of glasses, vases and bowls. Using shapes derived from the stems of objects in the Glass gallery, students can develop repeat patterns on paper or fabric. The project can easily be adapted for a wide range of ages.
Stems can be made in various ways. Drawn stems are so called because they are pulled from the same piece as the bowl of the glass or vase. The foot is made from a separate piece of glass and fused on afterwards. Other techniques involve making the bowl, stem and base in three separate pieces, or building the stem itself from several pieces, like 17th- and 18th- century English 'baluster' stems (so called because they are in the form of the short vertical post that supports a stair rail or parapet).
Some of the most striking glasses have 'serpent' or 'dragon' stems. First made in 17th-century Venice, these complicated stems are formed from twisted and interwoven lengths of glass. There are examples in Bay 11.
Air twist stems were developed in the 1730s and followed in the 1740s by the opaque white enamel twist. Both types can be seen in the case called The British Drinking Glass.
Air twist stems are made by incorporating bubbles of air into a gather or mass of hot glass, which is then quickly twisted and pulled. Opaque twists are formed by placing rods of white enamel in grooves on the inside of a cylindrical mould which is then filled with molten glass. When it cools slightly the whole mass is taken out of the mould and reheated and covered with another coating of clear glass. This is drawn out and twisted until it reaches the required thickness.
At the V&A
Students should draw stems of as many different shapes as possible. A good way of getting students to be accurate in their drawing is to ask them to draw the shapes (or 'negative space') between the stems. This encourages precise observation. The negative space can be shaded to exaggerate the silhouette effect. This method works particularly well with more complex stems.
Back at school
The stem drawings from the gallery can be turned into repeat patterns. Some ideas that you could try are:
Make simple card printing blocks from different stem shapes. The whole class could make a large collaborative print on paper or fabric
Make stencils of the stem shapes. Then transfer the pattern onto paper or fabric by spraying and sponging the stencils with paint or dye