Constitution‘s 52 heavy guns give her awesome power in battle, but they are useless without expert gun crews to fire them. To hone their skills, the seamen practice regularly, rehearsing a strict routine until they can do it blindfolded. Every man plays his part with furious concentration, for a naval gun can do as much harm to those who fire it as to the enemy. It weighs more than three tons, and rolling free, it will effortlessly crush a man. A stray spark on its powder charge will kill the gun crew and set the ship on fire.