Grapeshot was a kind of anti-personnel ammunition used in cannons, was similar to canister shot. The typical design is of a mass of loosely packed metal balls in a canvas bag that are intended to break apart at high velocity after being fired. It gives an effect similar to a shotgun scaled up to cannon size.
Napoleon, when a brigadier general during the later stages of the French Revolution, famously dispersed a Royalist mob on the streets of Paris with a "whiff of grapeshot" on 5 October1795. He was rewarded with the command of the Army of Italy in 1796, and his victories at the battles of Lodi, Castiglione, Arcola and Rivoli provided a springboard for his military and political ambitions.
Along with pellet shot and grapeshot, round shot was one of the early projectiles used in firearms.
As the name implies, round shot is spherical with a diameter slightly less than the bore of the firearm it is to be used in.
Round shot was popular during most of the age of sail, being replaced after the invention of the extruded bullet by Benjamin Robins at the end of the 1700s.