Huolongjing

Gunpowder and explosives

There were several gunpowder compositions proposed by Jiao Yu, with additions to the standard formula of potassium nitrate (saltpetre), sulphur, and charcoal by adapting gunpowder weapons to early chemical warfare. He described the suitable uses of "magic gunpowder", "poison gunpowder", or "blinding and burning gunpowder" in warfare, which displays the various compositions used in his time. For the making of poisonous gunpowder in hand-thrown or catapult-launched grenade bombs, he advised that a mixture of tung oil, urine, sal ammoniac, feces, and scallion juice be heated and coated upon tiny iron pellets and broken porcelain. For this, Jiao Yu wrote, "even birds flying in the air cannot escape the effects of the explosion". His book also outlined the use of the "flying-sand magic bomb releasing ten thousand fires", which included the use of a tube of gunpowder placed in an earthenware pot that was filled with quicklime, resin, and alcoholic extracts of poisonous plants.

During the 14th century, Chinese gunpowder solutions had reached their maximum explosive potential, with levels of nitrate ranging from 12% to 91%. At least six formulas in use by the Chinese that were considered to have reached the maximum explosive force for gunpowder. This came about because of the enrichment of sulphur from pyrite extracts during the earlier Song dynasty, while Chinese gunpowder formulas by the late 12th century and at least by 1230 were potent enough for explosive detonations and bursting cast iron shells. The root of all this was the 1044 military handbook, the Wujing Zongyao, which outlined the earliest formulas for gunpowder utilized in bombs hurled by catapults. Later, Wei Xing (d. 1164) of the Song Dynasty was said to have created a gunpowder formula of saltpetre, sulphur, and willow charcoal for his projectile carriages for launching "fire–stones" up to 400 yards (370 m).

Although its destructive force was widely recognized by the 11th century, the Chinese continued to refer to gunpowder as a "fire-drug" (huo yao) because of its original intended use for its pharmaceutical properties. Its value in festival entertainment could be seen in firework displays, such as during the martial demonstration of 1110 to entertain the court of Emperor Huizong. Leading up to its 10th-century usage in fire arrows and in fuses for igniting flamethrowers shooting Greek Fire, Daoist alchemists had experimented with various black powder solutions during the Han and Tang dynasties. After the Wujing Zongyao of 1044 explicitly described the formula for gunpowder, the central government became frightened that it could fall into the hands of neighboring enemies, and in 1076 enacted a strict governmental monopoly over the production and distribution of sulphur. Although saltpetre was a central component of the "fire-drug" and a flavor enhancer for food during the Tang and Song periods, in 1067 the Song government banned the populace of modern Shanxi and Hebei provinces to sell sulphur and saltpetre in any form to foreigners. While engaged in a war with the Mongols in 1259, the official Li Zengbo wrote in his text Ko Zhai Za Gao, Xu Gao Hou that the city of Qingzhou was manufacturing one to two thousand strong iron-cased bomb shells a month, dispatching to Xiangyang and Yingzhou about ten to twenty thousand such bombs at a time.

Fire arrows and rockets

Jiao Yu called the earliest fire arrows shot from bows (not rocket launchers) "fiery pomegranate shot from a bow" because the lump of gunpowder–filled paper wrapped around the arrow below the metal arrowhead resembled the shape of a pomegranate. He advised that a piece of hemp cloth should be used to strengthen the wad of paper and sealed with molten pine resin. Although he described the fire arrow in great detail, it was mentioned by the much earlier Xia Shaozeng, when 20,000 fire arrows were handed over to the Jurchen conquerors of Kaifeng City in 1126. An even earlier text, the Wujing Zongyao (武经总要, "Collection of the Most Important Military Techniques"), written in 1044 by Song scholars Zeng Gongliang and Yang Weide, described the use of three spring or triple bow arcuballista that fired arrow bolts holding gunpowder. Although written in 1630 (second edition in 1664), the Wulixiaoshi of Fang Yizhi said that fire arrows were presented to Emperor Taizu of Song in 960. Even after the rocket was invented in China the fire arrow continued to see use and were never entirely phased out; this could be seen in the Second Opium War when Chinese used fire arrows against the French in 1860.

By the time of Jiao Yu, the term "fire arrow" had taken on a new meaning and also referred to the earliest rockets found in China. The simple transition of this was to use a hollow tube instead of a bow or ballista firing gunpowder-impregnated fire arrows. The historian Joseph Needham wrote that this discovery came sometime before Jiao Yu during the late Southern Song Dynasty (1127–1279). From the section of the oldest passages in the Huolongjing, the text reads:

One uses a bamboo stick 4 ft 2 in long, with an iron (or steel) arrow–head 4.5 in long...behind the feathering there is an iron weight 0.4 in long. At the front end there is a carton tube bound on to the stick, where the 'rising gunpowder' is lit. When you want to fire it off, you use a frame shaped like a dragon, or else conveniently a tube of wood or bamboo to contain it.

In the late 14th century, the rocket launching tube was combined with the fire lance. This involved three tubes attached to the same staff. As the first rocket tube was fired, a charge was ignited in the leading tube which expelled a blinding lachrymatory powder at the enemy, and finally the second rocket was fired. An illustration of this appears in the Huolongjing, and a description of its effectiveness in obfuscating the location of the rockets from the enemy is provided. The Huolongjing also describes and illustrates two kinds of mounted rocket launchers that fired multiple rockets. There was a cylindrical, basket-work rocket launcher called the "Mr. Facing-both-ways rocket arrow firing basket", as well as an oblong-section, rectangular, box rocket launcher known as the "magical rocket-arrow block". Rockets described in the Huolongjing were not all in the shape of standard fire arrows and some had artificial wings attached. An illustration shows that fins were used to increase aerodynamic stability for the flight path of the rocket, which according to Jiao Yu could rise hundreds of feet before landing at the designated enemy target.

The Huolongjing also describes and illustrates the oldest known multistage rocket; this was the "fire-dragon issuing from the water" (huo long chu shui), which was known to be used by the Chinese navy. It was a two-stage rocket that had carrier or booster rockets that would automatically ignite a number of smaller rocket arrows that were shot out of the front end of the missile, which was shaped like a dragon's head with an open mouth, before eventually burning out. This multistage rocket is considered by some historians to be the ancestor of modern cluster munitions. Needham says that the written material and illustration of this rocket come from the oldest stratum of the Huolongjing, which can be dated to about 1300-1350 from the book's part 1, chapter 3, page 23.

Fire lance

The fire lance or fire tube—a combination of a firearm and flamethrower— had been adapted and changed into several different forms by the time Jiao Yu edited the Huolongjing. The earliest depiction of a fire lance is dated c. 950, a Chinese painting on a silk banner found at the Buddhist site of Dunhuang. These early fire lances were made of bamboo tubes, but metal barrels had appeared during the 12th century, and shot gunpowder flames along with "coviative" projectiles such as small porcelain shards or metal scraps. The first metal barrels were not designed to withstand high-nitrate gunpowder and a bore-filling projectile; rather, they were designed for the low-nitrate flamethrower fire lance that shot small coviative missiles. This was called the "bandit-striking penetrating gun" (ji zei bian chong). Some of these low–nitrate gunpowder flamethrowers used poisonous mixtures such as arsenious oxide, and would blast a spray of porcelain shards as shrapnel. Another fire lance described in the Huolongjing was called the 'lotus bunch' shot arrows accompanied by a fiery blast. In addition to fire lances, the Huolongjing also illustrates a tall, vertical, mobile shield used to hide and protect infantry, known as the "mysteriously moving phalanx-breaking fierce-flame sword-shield". This large, rectangular shield would have been mounted on wheels with five rows of six circular holes each where the fire lances could be placed. The shield itself would have been accompanied by swordsmen on either side to protect the gunmen.

Bombards, cannons, and guns

In China, the first cannon-barrel design portrayed in artwork was a stone sculpture dated to 1128 found in Sichuan province. The oldest extant cannon containing an inscription is a bronze cannon of China inscribed with the date, "2nd year of the Dade era, Yuan Dynasty" (1298). The oldest confirmed extant cannon is the Heilongjiang hand cannon ,dated to 1288 using contextual evidence. The History of Yuan records that in that year a rebellion of the Christian Mongol prince Nayan broke out and the Jurchen commander Li Ting who, along with a Korean brigade conscripted by Kublai Khan, suppressed Nayan's rebellion using hand cannons and portable bombards.

The predecessor of the metal barrel was made of bamboo, which was recorded in use by a Chinese garrison commander at Anlu, Hubei province, in the year 1132. One of the earliest references to the destructive force of a cannon in China was made by Zhang Xian in 1341, with his verse known as The Iron Cannon Affair. Zhang wrote that its cannonball could "pierce the heart or belly when it strikes a man or horse, and can even transfix several persons at once". Jiao Yu describes the cannon, called the "eruptor", as a cast bronze device which had an average length of 53 inches (130 cm). He wrote that some cannons were simply filled with about 100 lead balls, but others, called the "flying-cloud thunderclap eruptor" (飞云霹雳炮; feiyun pili pao) had large rounds that produced a bursting charge upon impact. The ammunition consisted of hollow cast iron shells packed with gunpowder to create an explosive effect. Also mentioned is a "poison-fog magic smoke eruptor," in which "blinding gunpowder" and "poisonous gunpowder" were packed into hollow shells used in burning the faces and eyes of enemies, along with choking them with a formidable spray of poisonous smoke. Cannons were mounted on frames or on wheeled carriages so that they could be rotated to change directions.

The Huolongjing also contains a hand held organ gun with up to ten barrels. For the "match-holding lance gun" (chi huo–sheng qiang), it described its arrangement as a match brought down to the touch hole of three gun barrels, one after the other. During the reign of the Yongle Emperor (1402–1424), the Shenji Brigade was formed with cavalry horses that were said to have tubes filled with flammable materials holstered to their sides, along with troops with firearms and light artillery on carriages.

Land mines and naval mines

The first recorded use of land mines occurred in 1227 when officer Lou Qianxia of the late Song Dynasty, who is credited with their invention, used them to kill Mongol soldiers. Jiao Yu wrote that land mines were spherical, made of cast iron, and their fuses were ignited by the enemy movement disturbing a trigger mechanism. Although his book did not elaborate on the trigger mechanism, a late Ming Dynasty book of 1606 said that a system utilizing a pin release, dropping weights, cords and axles worked to rotate a spinning "steel wheel" that acted as a flint to provide sparks that ignited the mines' fuses underground. For the use of naval mines, he wrote of slowly burning joss sticks that were disguised and timed to explode against enemy ships nearby:

The sea–mine called the 'submarine dragon–king' is made of wrought iron, and carried on a (submerged) wooden board, [appropriately weighted with stones]. The (mine) is enclosed in an ox-bladder. Its subtlety lies in the fact that a thin incense(–stick) is arranged (to float) above the mine in a container. The (burning) of this joss stick determines the time at which the fuse is ignited, but without air its glowing would of course go out, so the container is connected with the mine by a (long) piece of goat's intestine (through which passes the fuse). At the upper end the (joss stick in the container) is kept floating by (an arrangement of) goose and wild–duck feathers, so that it moves up and down with the ripples of the water. On a dark (night) the mine is sent downstream (towards the enemy's ships), and when the joss stick has burnt down to the fuse, there is a great explosion.

In the later Tiangong Kaiwu (The Exploitation of the Works of Nature) treatise, written by Song Yingxing in 1637, the ox bladder described by Jiao Yu is replaced with a lacquer bag and a cord pulled from a hidden ambusher located on the nearby shore, which would release a flint steel–wheel firing mechanism to ignite the fuse of the naval mine.

Legacy

Gunpowder warfare occurred in earnest during the Song dynasty. In China, gunpowder weapons underwent significant technological changes which resulted in a vast array of weapons that eventually led to the cannon. The cannon's first confirmed use occurred during the Mongol Yuan dynasty in a suppression of rebel forces by Yuan Jurchen forces armed with hand cannons. Cannon development continued into the Ming and saw greater proliferation during the Ming wars. Chinese cannon development reached internal maturity with the muzzle loading wrought iron "great general cannon" (大將軍炮), otherwise known by its heavier variant name "great divine cannon" (大神銃), which could weigh up to 1000 kilograms and was capable of firing several iron balls and upward of a hundred iron shots at once. The lighter "great general cannon" weighed up to 360 kilograms and could fire a 4.8 kilogram lead ball. The great general and divine cannons were the last indigenous Chinese cannon designs prior to the incorporation of European models in the 16th century.

When the Portuguese reached China in the early 16th century, they were unimpressed with Chinese firearms compared to their own. With the progression of the earliest European arquebus to the matchlock and the wheellock, and the advent of the flintlock musket of the 17th century, they surpassed the level of earlier Chinese firearms. Illustrations of Ottoman and European riflemen with detailed illustrations of their weapons appeared in Zhao Shizhen's book Shenqipu of 1598, and Ottoman and European firearms were held in great esteem. However by the 17th century Đại Việt had also been manufacturing muskets of their own, which the Ming considered to be superior to both European and Ottoman firearms, including Japanese imports as well. Vietnamese firearms were copied and disseminated throughout China in quick order.

The 16th-century breech-loading model entered China around 1517 when Fernão Pires de Andrade arrived in China. However, he and the Portuguese embassy were rejected as problems in Ming-Portuguese relations were exacerbated when the Malacca Sultanate, a tributary state of the Ming, was invaded in 1511 by the the Portuguese under Afonso de Albuquerque, and in the process a a large established Chinese merchant community was slaughtered. The Malacca Sultanate sent the Ming a plea for help but no relief expedition was sent. In 1521 the Portuguese were driven off from China by the Ming navy in a conflict known as the Battle of Tunmen.