I learned about four inventions this week and they are the ironing board, the internal combustion engine, repeating rifle, and the twist drill. First, I learned about the ironing board. Before the ironing board, people used to use rocks to smoothe cloths and the ironing board was invented in 1858. An ironing board is a long narrow board which you can iron clothes on and with a foam surface for absorbing heat. Home ironing was a much easier task and massive time saver.

Second, I learned about the internal combustion engine. The inventor of the combustion engine, Etienne Lenior, born in Belgium in 1822,  became interested in electricity and used sparks to invent the combustion engine. A combustion engine is an engine which generates power by combusting fuel. It led to jet engines and the Cold War.

Third, I learned about the repeating rifle. The inventor of the repeating rifle, Benjamin Tyler Henry, born in New Hampshire in 1821, worked for Smith & Wesson and developed the lever action rifle. A repeating rifle is a rifle designed with a spring-loaded tubular box holding metal bullets, each that go into the chamber by a lever, pump, or bolt and hold up to 16 bullets or 16.44 to be exact. Rifles were used for military combat and  they allowed a greater rate of fire. 
Finally, I learned about the twist drill. Rotary tools have long been used to bore holes and the bow drill helps make fire. Stevon A. Morse invented the twist drill in 1861. Twist drills are used to drill holes in materials such as plastic, wood, and steel. It was used to carve Mt. Rushmore and build the Hoover Dam.