General information. Good for finding out about a topic when you begin research. Includes up-to-date information sources and allows you to move easily to material of higher or lower reading levels as needed. User ID: icszlibrary Password: icszlibrary. Bronze Age During the stage in human history called the Bronze Age, people first began to use bronze to make tools, weapons, armor, and other implements.
Stone Age During the Stone Age, prehistoric humans and human ancestors made tools out of stone. Imagery and clip art materials infographics, signs and symbols, graphic concepts, and cool vector illustrations , all are rights-cleared for educational, non-commercial use. Password: icsz followed by your last name example: icszmatter.
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What was life like for early people before written records even began? Satisfy your child's curiosity about the lives of some of the first people with Eye Wonder: Early People. From the earliest human-like apes to the use of stone-age tools, from the discovery of fire to the dawn of agriculture and civilization, this book explores how the earliest people lived.
EAL It includes lots of sections that you'd find in newspapers, such as properties, arts, food and drink, advice, entertainment, etc. Why did ancient people in Peru create the Nazca Lines?
Who built England's Avebury Circle and why? What is the purpose of Easter Island's huge stone statues? Glass in its natural form has been with us since lightning first struck sand to produce fulgurites of fused quartz, which is to say long before humans started experimenting with what is now defined as an amorphous solid.
Glass can be traced back to BC when the Egyptians and Mesopotamians started to produce jewellery in the form of beads. There are of course thousands of other ways in which glass is deployed, from scientific and medical equipment to fibre-optics, from renewable energy to automotive, while in the world of materials science lively debate continues on what substances actually constitute glass.
The 20th century was to see significant innovations brought to glass production by Sir Alastair Pilkington. With more than 1. An alloy, it is made up almost exclusively of iron as much as 99 per cent , while its secondary component carbon contributes up to 2 per cent by weight.
Steel started its journey to ubiquity as a semi-precious metal, often produced in a haphazard way in bloomeries, a rudimentary type of smelting furnace. But by the Iron Age it was an established alternative to copper alloys. Because of its hardness, along with its ability to produce long-lasting sharp edges, it was vital to the arms industry. In prehistoric times, when steel was very rare, such was its value that when Alexander the Great defeated the ancient Indian king Porus he was rewarded not with gold, but steel.
A new breed of entrepreneurs such as Andrew Carnegie emerged to exploit this inexhaustible new material, casting rail networks across continents, building vertical cities in the form of skyscrapers and rolling out vast quantities of low-cost utility items such as cutlery.
Globally, production has shifted, with the recent economic boom in China and India creating mushrooming demand. China is currently the top producer, taking a one-third market share. The problem has always been that it only rarely occurs naturally in pure metallic form, and is locked away chemically in different minerals. Despite the difficulties in extracting aluminium, it is the second most used metal, with global production in at US journalists adopted that spelling, but the American Chemical Society only followed suit as recently as If ever there was a material that is both a blessing and a curse it is plastic.
Depending on your point of view, these petrochemical derivatives have the potential to stimulate the economies of emerging nations or create environmental meltdown. They contaminate our oceans and yet have made spaceflight possible. They are destructive and innovative. In fact, the only thing plastics really have in common is that they fall under a broad definition of synthetic or semi-synthetic organic compounds that are malleable and can be moulded.
The first man-made plastic was invented by metallurgist Alexander Parkes, who exhibited his Parkesine nitrocellulose compound intended to be a substitute for ivory at the Great London Exposition of , where it won a bronze medal.
The rest is history, with the material becoming a convenient and economic alternative for just about any engineering material imaginable: metals, wood, ceramics, stone or glass. Because commodity plastics are cheap, they are ubiquitous in food packaging, most of which has historically been thrown away, and because they have large molecules, decomposition rates are slow.
This, in turn, has led to the development of industries such as recycling and bioplastic. Iron tools were stronger than bronze tools. Weapons were more powerful. They did not show up in China until around BCE. The years assigned to each of these ages are a guess - they are not accurate because different civilizations developed at different speeds.
But looking back through time, each ancient civilization went though a Stone Age stone tools and weapons , then a Bronze Age bronze tools and weapons , then an Iron Age iron tools and weapons.
Weapons appeared in different civilizations at different times through invention, trade and conquest. Once better weapons arrived, they made a big difference. Each improvement in tools and weapons led to other improvements in each civilization, improvements such as new inventions, better production of food, and new or improved goods. These inventions depended upon the type of material discovered and then used.
Thus, the material used to make tool and weapons had a great influence on daily life in ancient times. The Stone Age cartoon, educational powerpoint for kids. The Bronze Age cartoon, educational powerpoint for kids. The Iron Age cartoon, educational powerpoint for kids.
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