The Huolongjing known as Huoqitu, is a 14th-century military treatise compiled and edited by Jiao Yu and Liu Bowen of the early Ming dynasty. The Huolongjing is based on the text known as Huolong Shenqi Tufa, no longer extant; the Huolongjing's intended function was to serve as a guide to "fire weapons" involving gunpowder from 1280 to the mid-14th century. The Huolongjing provides information on various gunpowder weapons; some formulas mentioned are given names such as "divine gunpowder", "poison gunpowder", "blinding and burning gunpowder". The weapons described include bombs, fire arrows, land mines, naval mines, fire lances, hand cannons, cannons mounted on wheeled carriages. Although the earliest edition of the Huolongjing was published in Xiangyang sometime prior to 1395, its preface was not provided until the Nanyang publication of 1412; the 1412 edition, known as Huolongjing Quanji, remains unchanged from its predecessor with the exception of its preface, which provides an account of Jiao Yu's time in the Hongwu Emperor's army.

In the preface Jiao Yu claims to describe gunpowder weapons that had seen use since 1355 during his involvement in the Red Turban Rebellion and revolt against the Yuan dynasty, while the oldest material found in his text dates to 1280. A second and third volume to the Huolongjing known as Huolongjing Erji and Huolongjing Sanji were published in 1632 with content describing weapons such as the musket and breech-loading cannons. After the end of the Ming dynasty, the Qing dynasty outlawed reprinting of the Huolongjing for using expressions such as'northern barbarians,' which offended the ruling Manchu elite. Although its destructive force was recognized by the 11th century, gunpowder continued to be known as a "fire-drug" because of its original intended pharmaceutical properties; however soon after the chemical formula for gunpowder was recorded in the Wujing Zongyao of 1044, evidence of state interference in gunpowder affairs began appearing. Realizing the military applications of gunpowder, the Song court banned private transactions involving sulphur and saltpeter in 1067 despite the widespread use of saltpeter as a flavor enhancer, moved to monopolize gunpowder production.

In 1076 the Song prohibited the populaces of Hedong and Hebei from selling sulphur and saltpetre to foreigners. In 1132 gunpowder was referred to for its military values for the first time and was called "fire bomb medicine" rather than "fire medicine". While Chinese gunpowder formulas by the late 12th century and at least 1230 were powerful enough for explosive detonations and bursting cast iron shells, gunpowder was made more potent by applying the enrichment of sulphur from pyrite extracts. Chinese gunpowder solutions reached maximum explosive potential in the 14th century and at least six formulas are considered to have been optimal for creating explosive gunpowder, with levels of nitrate ranging from 12% to 91%. Evidence of large scale explosive gunpowder weapons manufacturing began to appear. While engaged in war with the Mongols in 1259, the official Li Zengbo wrote in his 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, delivered them to Xiangyang and Yingzhou in loads of about ten to twenty thousand shells at a time.

The Huolongjing's primary contribution to gunpowder was in expanding its role as a chemical weapon. Jiao Yu proposed several gunpowder compositions in addition to the standard potassium nitrate and charcoal. Described are the military applications of "divine gunpowder", "poison gunpowder", "blinding and burning gunpowder." Poisonous gunpowder for hand-thrown or trebuchet launched bombs was created using a mixture of tung oil, sal ammoniac and scallion juice heated and coated upon tiny iron pellets and broken porcelain. According to Jiao Yu, "even birds flying in the air cannot escape the effects of the explosion". Explosive devices include the "flying-sand divine bomb releasing ten thousand fires", which consisted of a tube of gunpowder placed in an earthenware pot filled with quicklime and alcoholic extracts of poisonous plants. Jiao Yu called the earliest fire arrows shot from bows "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 earlier text, the Wujing Zongyao, 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, the Wulixiaoshi of Fang Yizhi said that fire arrows were presented to Emperor Taizu of Song in 960. After the rocket was invented in China the fire arrow was never phased out: it saw use 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 referred to the

Natural point of aim

Natural point of aim known as "Natural Aiming Area", is a shooting skill where the shooter minimizes the effects of body movement on the firearm's impact point. Along with proper stance, sight alignment, sight picture, breath control, trigger control, it forms the basis of marksmanship. To achieve natural point of aim, the shooter settles into position while not looking through the sights; some shooters close their eyes, but this can upset the natural maintenance of balance because the brain uses visual cues to help stay in balance. The shooter looks through the sights only after ensuring the position is comfortable and the firearm is resting in the stance with minimal muscle tension. If the sights are not resting on the desired point of impact, the shooter adjusts the position by repeating the same steps until the sights rest on the target. After achieving a comfortable and natural position, if the sights are not on the target, the shooter adjusts his stance until the sights are on target; the arm and body position do not change.

Natural point of aim is not achieved if the shooter must apply pressure to the firearm so the sight picture is on target. One of the main advantages of natural point of aim is that it minimizes fatigue when shooting a long course of fire. Over time, the shooter learns to assume the correct position allowing for accurate fire immediately; the main purpose of identifying and correcting natural point of aim is to make shots with both accuracy and precision, where accuracy is the ability to place rounds on the desired target, precision is the ability to put multiple rounds in the same location. Good shooters are always precise, this skill is more fundamental than accuracy, which can be adjusted. Precision is based on natural point of aim. Fire 10 rounds downrange and they will all land in a similar area on the target; this is the natural point of aim. If the strike zone is not in the middle of the target, adjustments are made to the shooter's positioning and/or the firearm's sights so that the shots strike the centre of the target.

Natural point of aim marksmanship is based on the idea that muscular control is insufficient to provide a stable platform for shooting more than one shot. Instead, the shooter relies on non-muscular support to provide the shooting platform; this eliminates changes in aim due to muscle fatigue and minimizes the shaking associated with muscle tension. Natural point of aim is a concept that can be used in relation to any type of shooting position but is most discussed in relation to prone, sitting, or kneeling positions, less with offhand/standing positions

Southland Field

Southland Field is a public-use airport located five nautical miles south of the central business district of Sulphur, a city in Calcasieu Parish, United States. It is owned by the West Calcasieu Airport Managing Board and is known as West Calcasieu Airport; this airport is included in the FAA's National Plan of Integrated Airport Systems for 2009–2013, which categorized it as a general aviation facility. Although many U. S. airports use the same three-letter location identifier for the FAA and IATA, this facility is assigned UXL by the FAA but has no designation from the IATA. Southland Field covers an area of 278 acres at an elevation of 10 feet above mean sea level, it has one runway designated 15/33 with an asphalt surface measuring 5,001 by 75 feet. For the 12-month period ending July 6, 2009, the airport had 19,690 aircraft operations, an average of 53 per day: 99% general aviation and 1% military. At that time there were 29 aircraft based at this airport: 72% single-engine, 17% multi-engine and 10% ultralight.

Southland Aviation, the fixed-base operator FAA Terminal Procedures for UXL, effective February 27, 2020 Resources for this airport: FAA airport information for UXL AirNav airport information for KUXL FlightAware airport information and live flight tracker NOAA/NWS weather observations: current, past three days SkyVector aeronautical chart, Terminal Procedures