1 Discard any hammer with mushroomed or chipped face or with cracks in the claw or eye sections. 2  Wear safety glasses or goggles, or a face shield (with safety glasses or goggles).  Strike a hammer blow squarely with the striking face parallel to the surface being struck.
The first jet airplane was the Heinkel He 178 made in Germany in 1939, right before the outbreak of World War II .
Most people think about Orville and Wilbur Wright. And, December 17, 1903 is the day to remember. That was the day that Orville won the toss of the coin. He made the first successful powered flight in history! The place was Kitty Hawk, North Carolina. The Wright Brothers' dream of inventing a flying machine had come true.