Flintlock, a firing mechanism used on early firearms. It was first used on muskets about 1650, later on pistols. The cock, or hammer, of the flintlock held a piece of flint which, when the trigger was pulled, struck a piece of steel and caused sparks to fly. The sparks ignited a small priming charge of powder in a pan, which was uncovered as the flint struck the steel. The fire flashed through a touchhole, exploding the main powder charge and discharging the ball (bullet). By about 1850 flintlocks had been replaced by percussion locks.
So you're a would-be Tony Stark. But how much do you actually know about powered exoskeletons, aka "Iron Man" suits? Test your knowledge with our Fact or Fiction quiz.
The Vietnam War occurred decades ago, but one of its legacies lingers on in Vietnamese soil and the U.S. court system. How did this defoliant do so much damage?