Heated shot

. A Spanish floating battery is shown exploding after the British defenders set it on fire with heated shot The idea of setting fire to enemy warships can be traced back to the ancient world, where fire arrows and incendiary materials such as Greek fire were used. In 54 BC, heated clay balls were used by the Britons to attack Roman encampments, while in medieval siege warfare, catapults were used to hurl fire balls and other incendiaries into besieged castles and settlements. • The first successful use of heated shot fired from cannon was by King Stephen Bathory of Poland in 1579 against the Russians at Polotsk. From that time on the use of heated projectiles became increasingly important, especially against wooden warships of the period. • During the American Revolutionary War, French artillerymen destroyed the British frigate HMS Charon using heated shot during the Battle of Yorktown in 1781. • In 1782, during the Great Siege of Gibraltar, French and Spanish forces attempted to use large floating batteries to bombard the British defenders. The batteries were of extremely heavy construction and were considered to be invincible. British artillery in Gibraltar used heated shot to destroy three of the ten batteries, inflicting a loss of 719 crewmen. The remaining seven were scuttled by the Spanish due to heavy damage. • In 1792, Austrian forces besieging Lille used heated shot against the city, which was described as a war crime by the French Republican press. • In July 1801, during the Second Battle of Algeciras, two Spanish ships of the line exploded killing nearly 1,700 members of their crews. According to various sources, the fire that caused the explosions of both ships originated from heated shots fired by . • In 1817, the Negro Fort, a fort inhabited by fugitive slaves escaping slavery in the United States was obliterated when a heated shot (heated in a boat galley) fired by an American gunboat landed in the Fort's powder magazine. The resulting explosion killed about 270 and wounded 30 others. • One of the last significant uses of heated shot in naval warfare occurred in 1862, at the Battle of Hampton Roads, when the CSS Virginia used heated shot to great effect against USS Congress, setting her on fire. ==Operation==

Hot-shot furnaces (1779–83) The original method of heating round shot was to cover them in the coals of a large wood fire, or heat them on metal grates placed over a fire pit. These time-consuming methods were improved by the French, who used specially-constructed furnaces to heat shot in their artillery batteries at the mouth of the Rhône River in 1794, although artillery units would continue to use a grate constructed of iron bars and earth when a purpose-built shot furnace was unavailable. A hot furnace could heat a 24 pounder shot in around 25 minutes, with larger shot taking a few minutes longer. If the furnace was cold, heating shot could take up an hour and a quarter after lighting the fire. Three men were required to manage a furnace. One maintained the fire and added cold shot, a second man removed heated shot from the furnace, and the third man cleaned them. Special tools were required to handle heated shot. An iron fork was used to remove heated shot from the furnace, then the shot was placed on a stand and cleaned by rubbing off loose surface scale with a rasp. A pair of tongs with circular jaws was used to handle the shot at the furnace. To carry the shot to the cannons, hot-shot ladles were used. The ladles had an iron cup for the shot with one or three handles. Round shot less than weight size could be carried by one man with a single-handle ladle, while larger shot needed a three-handle ladle, carried between two men like a stretcher. Loading Great care had to be taken loading heated shot into a cannon to ensure that the red-hot shot did not prematurely ignite the cannon's charge of gunpowder. A cartridge bag of gunpowder was loaded first. A double bag was used with heated shot to prevent leakage of grains of gunpowder as the bag was rammed down the cannon. Once the bag was in place, a dry wad of hay or cloth was rammed down against the bag, followed by a wad of wet hay, clay or fuller's earth. If the cannon was to be fired at a downward angle, another wet wad was rammed against the ball to prevent it from rolling out. If proper loading precautions were taken, the wet wad could protect the gunpowder cartridge from premature ignition even until the heated shot had cooled down. However it was better to fire the gun quickly as water boiled from the wet wad could condense in the gunpowder charge if there was an excessive delay. A common practice with heated shot was to fire it with a reduced charge of gunpowder - as little as a quarter or a sixth the charge used for shooting a cold shot over the same distance. Also, if a shot embedded itself too deeply into the target, insufficient air would reach it to effectively start a fire before it cooled down. At least one of these has been found at Fort Pillow, Tennessee, the site of the 1864 Battle of Fort Pillow during the American Civil War. ==Molten iron shells==

In 1860, the Martin molten iron shell was introduced to Royal Navy service. These shells were filled with iron melted in a cupola furnace and were intended to break up on impact, splashing molten iron on the target and setting fire to any combustible material present. The shells were named after their designer, an employee of the Royal Laboratory at the Royal Arsenal. The interior was lined with a mixture of horsehair and loam for insulation. The furnace installation, known as ''Anderson's Cupola''. Various sizes of shells were tested, but it was found that only the largest shells had a useful incendiary effect. Experiments were carried out in 1859 using the aged, redundant frigate HMS Undaunted as a target. The first three shells were ineffectual, but after the fourth and fifth had been fired, a fire had been started on ''Undaunted's'' lower deck that could not be put out with her fire fighting equipment. The ship was finally sunk with conventional shells. The system was declared obsolete in 1869. == Gallery ==

File:Fort Jefferson FL25.jpg|Fort Jefferson, Florida, USA File:Hotshot furnace Fort Marion (Castillo de San Marcos).jpg|Fort Marion, Florida, U.S. File:Four à boulets de la batterie des Braves Gens 1.jpg|Île Saint-Honorat, France File:Ile Sainte-Maguerite - Four a boulet.JPG|Île Sainte-Marguerite, France File:Hot Shot furnace at Fort McAllister, GA, US.jpg|Hot Shot furnace at Fort McAllister ==See also==