Siege warfare of the Ancient Greeks and Romans, 18th century engraving. In the foreground is a rolling panel used to shield engineers attacking walls during a siege. The flaming torch and burning cauldron would be used by city defenders to try to set fire to an attacker's siege machines. Behind is a siege tower and the pulley system used to move it up to a wall. The tower moves on logs rolling over a surface of planks, with new logs being placed in front of the tower through a hatch by men inside. Behind the tower is a huge animal-headed battering ram inside a shed built to protect it and its crew from enemy missiles. In the distance is another siege tower.