CHAPTER ONE Discoveries and Inventions Two That Got Us Started Since our earliest days mankind’s desire to learn more about the world has led to important inventions and discoveries In working to solve problems understand ourselves and our universe and make everyday life easier we are motivated to search study and build Inventions and discoveries are not the same thing Discoveries occur when people learn something new about the world that they didn’t know before An invention is a new device created by a person or by a group of people Often times inventions lead to new discoveries Satellites are inventions that have lead us to new discoveries about the Earth and space 4
Sometimes inventions are the brainchild of one person More often they are the result of many different people building on and adding to the developments of those who came before them Sometimes they come in a flash an Aha moment but usually inventions are the result of trial and error Success comes through determination and hard work 5
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
