which means "stone probe", that may have been used for acupuncture purposes.: 70 the ancient chinese medical text, huangdi neijing, indicates that sharp stones were believed at-the-time to cure illnesses at or near the body's surface, perhaps because of the short depth a stone could penetrate.: 71 however, it is more likely that stones were used for other medical purposes, such as puncturing a growth to drain its pus. the mawangdui texts, which are believed to be from the 2nd century bc, mention the use of pointed stones to open abscesses, and moxibustion, but not for acupuncture. it is also speculated that these stones may have been used for bloodletting, due to the ancient chinese belief that illnesses were caused by demons within the body that could be killed or released. it is likely bloodletting was an antecedent to acupuncture. according to historians lu gwei-djen and joseph needham, there is substantial evidence that acupuncture may have begun around 600 bc. some hieroglyphs and pictographs from that era suggests acupuncture and moxibustion were practised. however, historians lu and needham said it was unlikely a needle could be made out of the materials available in china during this time period.: 71–72 it is possible that bronze was used for early acupuncture needles. tin, copper, gold and silver are also possibilities, though they are considered less likely, or to have been used in fewer cases.: 69 if acupuncture was practised during the shang dynasty (1766 to 1122 bc), organic materials like thorns, sharpened bones, or bamboo may have been used.: 70 once methods for producing steel were discovered, it would replace all other materials, since it could be used to create a very fine, but sturdy needles.: 74 lu and needham noted that all the ancient materials that could have been used for acupuncture and which often produce archaeological evidence, such as sharpened bones, bamboo or stones, were also used for other purposes. an article in rheumatology said that the absence of any mention of acupuncture in documents found in the tomb of mawangdui from 198 bc suggest that acupuncture was not practised by that time. belief systems several different and sometimes conflicting belief systems emerged regarding acupuncture. this may have been the result of competing schools of thought. some ancient texts referred to using acupuncture to cause bleeding, while others mixed the ideas of blood-letting and spiritual ch'i energy. over time, the focus shifted from blood to the concept of puncturing specific points on the body, and eventually to balancing yin and yang energies as well. according to david ramey, no single "method or theory" was ever predominantly adopted as the standard. at the time, scientific knowledge of medicine was not yet developed, especially because in china dissection of the deceased was forbidden, preventing the development of basic anatomical knowledge. it is not certain when specific acupuncture points were introduced, but the autobiography of bian que from around 400–500 bc references inserting needles at designated areas. bian que believed there was a single acupuncture point at the top of one's skull that he called the point "of the hundred meetings.": 83 texts dated to be from 156–186 bc document early beliefs in channels of life force energy called meridians that would later be an element in early acupuncture beliefs. ramey and buell said the "practice and theoretical underpinnings" of modern acupuncture were introduced in the yellow emperor's classic (huangdi neijing) around 100 bc. it introduced the concept of using acupuncture to manipulate the flow of life energy (qi) in a network of meridian (channels) in the body. the network concept was made up of acu-tracts, such as a line down the arms, where it said acupoints were located. some of the sites acupuncturists use needles at today still have the same names as those given to them by the yellow emperor's classic.: 93 numerous additional documents were published over the centuries introducing new acupoints.: 101 by the 4th century ad, most of the acupuncture sites in use today had been named and identified.: 101 establishment and growth in the first half of the 1st century ad, acupuncturists began promoting the belief that acupuncture's effectiveness was influenced by the time of day or night, the lunar cycle, and the season.: 140–41 the 'science of the yin-yang cycles' (運氣學 yùn qì xué) was a set of beliefs that curing diseases relied on the alignment of both heavenly (tian) and earthly (di) forces that were attuned to cycles like that of the sun and moon.: 140–41 there were several different belief systems that relied on a number of celestial and earthly bodies or elements that rotated and only became aligned at certain times.: 140–41 according to needham and lu, these "arbitrary predictions" were depicted by acupuncturists in complex charts and through a set of special terminology. acupuncture needles during this period were much thicker than most modern ones and often resulted in infection. infection is caused by a lack of sterilization, but at that time it was believed to be caused by use of the wrong needle, or needling in the wrong place, or at the wrong time.: 102–03 later, many needles were heated in boiling water, or in a flame. sometimes needles were used while they were still hot, creating a cauterizing effect at the injection site.: 104 nine needles were recommended in the great compendium of acupuncture and moxibustion from 1601, which may have been because of an ancient chinese belief that nine was a magic number.: 102–03 other belief systems were based on the idea that the human body operated on a rhythm and acupuncture had to be applied at the right point in the rhythm to be effective.: 140–41 in some cases a lack of balance between yin and yang were believed to be the cause of disease.: 140–41 in the 1st century ad, many of the first books about acupuncture were published and recognized acupuncturist experts began to emerge. the zhen jiu jia yi jing, which was published in the mid-3rd century, became the oldest acupuncture book that is still in existence in the modern era. other books like the yu gui zhen jing, written by the director of medical services for china, were also influential during this period, but were not preserved. in the mid 7th century, sun simiao published acupuncture-related diagrams and charts that established standardized methods for finding acupuncture sites on people of different sizes and categorized acupuncture sites in a set of modules. acupuncture became more established in china as improvements in paper led to the publication of more acupuncture books. the imperial medical service and the imperial medical college, which both supported acupuncture, became more established and created medical colleges in every province.: 129 the public was also exposed to stories about royal figures being cured of their diseases by prominent acupuncturists.: 129–35 by time the great compendium of acupuncture and moxibustion was published during the ming dynasty (1368–1644 ad), most of the acupuncture practices used in the modern era had been established. decline by the end of the song dynasty (1279 ad), acupuncture had lost much of its status in china.: 25 it became rarer in the following centuries, and was associated with less prestigious professions like alchemy, shamanism, midwifery and moxibustion.: 25 additionally, by the 18th century, scientific rationality was becoming more popular than traditional superstitious beliefs. by 1757 a book documenting the history of chinese medicine called acupuncture a "lost art".: 160 its decline was attributed in part to the popularity of prescriptions and medications, as well as its association with the lower classes.: 188 in 1822, the chinese emperor signed a decree excluding the practice of acupuncture from the imperial medical institute. he said it was unfit for practice by gentlemen-scholars.: 308 in china acupuncture was increasingly associated with lower-class, illiterate practitioners.: 58 it was restored for a time, but banned again in 1929 in favor of science-based western medicine. although acupuncture declined in china during this time period, it was also growing in popularity in other countries. international expansion acupuncture chart from shisi jing fahui (expression of the fourteen meridians) written by hua shou (fl. 1340s, ming dynasty). japanese reprint by suharaya heisuke (edo, 1. year kyōhō = 1716). korea is believed to be the first country in asia that acupuncture spread to outside of china. within korea there is a legend that acupuncture was developed by emperor dangun, though it is more likely to have been brought into korea from a chinese colonial prefecture in 514 ad.: 262–63 acupuncture use was commonplace in korea by the 6th century. it spread to vietnam in the 8th and 9th centuries. as vietnam began trading with japan and china around the 9th century, it was influenced by their acupuncture practices as well. china and korea sent "medical missionaries" that spread traditional chinese medicine to japan, starting around 219 ad. in 553, several korean and chinese citizens were appointed to re-organize medical education in japan and they incorporated acupuncture as part of that system.: 264 japan later sent students back to china and established acupuncture as one of five divisions of the chinese state medical administration system.: 264–65 acupuncture began to spread to europe in the second half of the 17th century. around this time the surgeon-general of the dutch east india company met japanese and chinese acupuncture practitioners and later encouraged europeans to further investigate it.: 264–65 he published the first in-depth description of acupuncture for the european audience and created the term "acupuncture" in his 1683 work de acupunctura. france was an early adopter among the west due to the influence of jesuit missionaries, who brought the practice to french clinics in the 16th century. the french doctor louis berlioz (the father of the composer hector berlioz) is usually credited with being the first to experiment with the procedure in europe in 1810, before publishing his findings in 1816.: 308 by the 19th century, acupuncture had become commonplace in many areas of the world.: 295 americans and britons began showing interest in acupuncture in the early 19th century, although interest waned by mid-century. western practitioners abandoned acupuncture's traditional beliefs in spiritual energy, pulse diagnosis, and the cycles of the moon, sun or the body's rhythm. diagrams of the flow of spiritual energy, for example, conflicted with the west's own anatomical diagrams. it adopted a new set of ideas for acupuncture based on tapping needles into nerves. in europe it was speculated that acupuncture may allow or prevent the flow of electricity in the body, as electrical pulses were found to make a frog's leg twitch after death. the west eventually created a belief system based on travell trigger points that were believed to inhibit pain. they were in the same locations as china's spiritually identified acupuncture points, but under a different nomenclature. the first elaborate western treatise on acupuncture was published in 1683 by willem ten rhijne.: 75 modern era an ancient acupuncture statue at the lobby of the emperor's college clinic, california in china, the popularity of acupuncture rebounded in 1949 when mao zedong took power and sought to unite china behind traditional cultural values. it was also during this time that many eastern medical practices were consolidated under the name traditional chinese medicine (tcm). new practices were adopted in the 20th century, such as using a cluster of needles,: 164 electrified needles, or leaving needles inserted for up to a week.: 164 a lot of emphasis developed on using acupuncture on the ear.: 164 acupuncture research organizations such as the international society of acupuncture were founded in the 1940s and 1950s and acupuncture services became available in modern hospitals. china, where acupuncture was believed to have originated, was increasingly influenced by western medicine. meanwhile, acupuncture grew in popularity in the us. the us congress created the office of alternative medicine in 1992 and the national institutes of health (nih) declared support for acupuncture for some conditions in november 1997. in 1999, the national center for complementary and alternative medicine was created within the nih. acupuncture became the most popular alternative medicine in the us. politicians from the chinese communist party said acupuncture was superstitious and conflicted with the party's commitment to science. communist party chairman mao zedong later reversed this position, arguing that the practice was based