Page 43 - Curriculum Visions Dynamic Book

See Vol. 1: Plastics and Vol. 7: Fibres for more on kevlar.
Breastplate
Gauntlet
(Above) Body armor in
the Middle Ages was made from sheet iron and chain mail. The parts were riveted together to allow a small amount of movement.
Lead was another metal discovered in ancient times. It was originally found in rocks containing silver. The Greeks were the first to use lead, although it is perhaps best known for its use in water systems by the Romans. Their word for lead was plumbum, and they used it to make water pipes, hence our modern word “plumbing” for water-pipe work.
Mercury was another metal that was known in ancient times. This metal also has the distinction of being a liquid at room temperature. Mercury has many uses, but it also has the disadvantage of being extremely poisonous.
Metals before the Industrial
Revolution
Ancient civilisations recognised that metals could
sometimes do what other materials could not. Weaponry was one of the first examples. The reason for this is that we have always lived in troubled times, and so the first task is to protect yourself. Only then can you have the time and luxury to use metals for the other things you might want (see page 43).
We would not think the metals used for swords in ancient times – bronze and copper – very suitable because they were soft, could not keep a sharp edge, and were easily damaged in battle. Copper blades were made somewhat harder by hammering them. Nevertheless, they were, in their day, state of the art. As new metals – iron and steel – became available, they were first put to use in making better weapons.
However, metals can be used to such an extent that they become a liability rather than a help. In the Middle Ages in Europe body armor was developed so far that a man could be totally enclosed in a suit of iron armor. But it weighed so much, he could not move around. He could only do battle on a horse, but the weight meant that only a big horse was built strong enough to carry him.
Knights were hoisted onto their horses using cranes. Once the knight was upright, all he could do
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