This acoustic filter invented El Delores Jones in 1917, after which the world around us has become a bit quieter.
4. Circular Saw
Tabitha Babbitt, 1779 was an early American and Shaker tool maker and inventor, including inventions for the circular saw, spinning wheel head and false teeth. Before which the men used saw with two handles moving it front and back. Babbitt thought it was a waste of energy, and in 1810 created a prototype of a circular saw, which later came to be used in the sawmill industry.