In 1944 alone, the United States built more planes than the Japanese did from 1939 to 1945. By the end of the war, more than half of all industrial production in the world would take place in the United States.
The welt-beating and slashing machine ensures the welt is parallel to the insole. The outsole is then covered with rubber cement and attached to the upper using a sole-laying machine. The sole is stitched to the rest of the shoe using a lockstitch machine, capable of making 1,000 stitches in a minute.
A machine is a tool used to make work easier. Simple machines are simple tools used to make work easier. They have few or no moving parts. There are 6 simple machines: Inclined Plane, Wedge, Screw, Lever, Wheel and Axle, and Pulley. Compound machines have two or more simple machines working together to make work easier. Most of the machines we use today are compound machines, created by combining several simple machines.