Click to viewThis terrifying slow motion video shows the destructive power of a tank canister shot, blazing across an entire battlefield. It's so spectacularly crystal-clear that you can easily understand why it is one of the most feared weapons by infantry soldiers. The canister shot is not new, however. This simple and incredibly effective technology has been wreaking havoc in ground fronts since the Napoleonic Wars. Designed to create a destructive cloud to do major damage on a large group of soft bodies, the canister shot has played a central role in ground battles since the 18th century. The first time I read an account of its deadly power was in a book called A Day of Anger, describing how it literally made the streets of Madrid red with blood in the urban guerrilla battle that started the Spanish Independence War against the French. In this video you can see how it works: A cylindrical metal canister is filled with lead or iron balls and sawdust, used to firmly pack the metal balls while avoiding them to crowding each other when the cannon fires. Basically, this type of shell turns the large tank cannon into a giant shotgun. And like a shotgun, its destructive power at close range is now mostly used in urban warfare.