One of the earliest examples of a primitive entry device, The Petard goes back to the 16th Century. Possibly invented by The French, in theory – the device was a conical or bell shaped iron pot filled with powder and small solid shot. Mounted on a wooden brace or carriage, The Petard would be placed directly against a fortified door or light wall. A fuse was ignited. The resulting explosion would blast a hole in the intended object. This would then aid troops in exploited the man-made breach. Several Petards could be placed side by side to inflict even more damage. Roughly, 5 to 6 pounds of gunpowder was needed to achieve it' desired effect. The Petard was an effective late-siege weapon.