Fire Now We’re Cooking Fire has always been important to humans We use it for warmth We cook with it Early humans unable to make their own fire noticed that lightning set fire to dry grass and brush They learned to gather burning sticks and embers and use them to start their own campfires Then people used wood to start fires The larger piece of wood would have a small dip in the center A person would set the larger piece on the ground and place dry grass in the dip Then he would put one end of the second stick in the dip and rotate it rapidly between his palms After awhile the friction between the sticks would raise the temperature enough to ignite the dry grass Men learned to make fire by rubbing two pieces of wood together 6
Fire Plough Method Circular motion creates friction Set bark beneath notch When early humans discovered how to start fire they also learned how to cook with fire 7
Lens Eventually the invention of the bow drill made it easier and faster to start friction fires Using a bow a person could turn the wood more quickly and more steadily He also had a free hand with which he could hold another piece of wood on top of the drill to exert downward force based Method Others created sparks by striking flint against pyrite then adding dry grass and twigs to get a fire going Later Greeks Chinese and other ancient civilizations learned to start fires using curved lenses They held the lens in the sunlight and directed the Sun’s rays onto kindling Fire started quickly under the Sun’s concentrated rays Flint and Steel Method 8 Flint Pyrite
B A D E C Bow and Drill Method A Socket B Drill C Fireboard D Bow E Cord In 1827 a man named John Walker invented friction matches pieces of wood coated at one end with chemicals Striking the match on a hard surface caused the chemicals to burst into flame Now disposable lighters provide instant fire at the flick of a thumb 9
