The Machine Gun
The Machine Gun was revealed as a great turning point in the way the war was fought. It was an American created weapon that brought control over the battlefield.
Sir Hiram Maxim (left picture) born in 1840 and died in 1916 was the original creator of the Machine Gun. He wanted to figure out a system for faster firing and realized that he could use the power of the recoil to set the next round into place. Essentially Maxim's design was sold to the british (which can be seen in the right picture) The first account of the British using this new weapon effectively was in 1893-1894 (Duffy, Michael. "Who's Who - Sir Hiram Maxim") Once people realized how effective the new machine was, they started to create new versions all across Europe. The Battle of Somme is a great example of German troops using the Machine Gun to their advantage.
"During the bombardment the German troops sought effective shelter in such bunkers, emerging only with the ceasing of the British artillery bombardment, when the German machine guns are manned to great effect." (Hickman)