From crossing rivers to hauling heavy loads, this title of the Crafty Inventions series poses the problems that lead to 10 of the very first inventions. Work out how the wheel transformed people s everyday lives and why the spear became a cutting edge weapon. Then re-create a cave painting, build a hut-on-stilts and craft your own raft, bridge and water dipper. Table of Contents: Spearheads Aerodynamics Early wheels Friction Earth ramp Inclined plane The first plough Wedges The shadoof Levers Log raft Floating and sinking Bridge supports Stress Safe Shelter Building materials Paints and Pigments Binders Papyrus Paper-making Glossary and Index Tools and materials
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