|MadSci Network: Science History|
Yes, indeed there were exploding cannonballs! Although some cannonballs were heated to red heat to cause fires when they landed (for example, in an enemy ship's sails). Truely exploding cannonballs were hollow. They were filled with black powder through a hole usually about an inch in diameter. The hole was filled with a plug with a hole through it. The plug was recessed into the cannonball shell (not sticking out as often shown in cartoons). Through the hole was passed a short wick - usually a short piece of rope soaked in some cumbustible material. The entire plug/wick apparatus was called a fuse. After the cannon was packed with powder and tamped, etc., the cannonball wick was lighted and quickly dropped into the cannon - which was then fired quickly. The wick was designed so that there was enough time to get it into the cannon, get the cannon fired, and still have enough time left to get to the enemy before it exploded. Obviously, this was a pretty important thing to get right (don't want the cannonball going off in your hand or in your cannon). A specialist, called a fusileer, was in charge of figuring out the right type of fuse and length of wick to install for hitting certain kinds of targets. Modern fuses are much more sophisticated. They can be denoted by time, GPS position, radar-wave reflections, magnetic signatures, etc. They can be set either before they are fired or set by radio or magnetic as the projectile shoots out the gun barrel at 2000 ft/sec!
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