In old times, hunters didn't have guns and cool stuff to help get food. They had to come up with a new and genius way to hunt animals for delicious food. Around 21,000 years ago, some people in the modern day french area came up with the idea of using a lever arm to be able to throw a spear faster, farther, and more accurate. The way in which this device works is that it acts on a lever arm. Since the throwing arm is long more force is applied to the object, effectively multiplying the force put into the spear.