JAPAN, FLAG OF

national flag consisting of a white field bearing a central red disk (a stylized sun). The flag has a width-to-length ratio of 2 to 3. According to tradition, the sun goddess Amaterasu founded Japan in the 7th century BC and was an ancestor of the first of its emperors, Jimmu. Even today the emperor is known as the Son of the Sun, and a popular name for the country is Land of the Rising Sun. The first concrete evidence that testifies to use of a sun flag for Japan dates from 1184, but there are oral traditions going back centuries earlier. The current form of the flag was officially adopted on August 5, 1854, when Japan was beginning to open up to commerce and diplomatic relations with European countries. Its use on land was only slowly accepted by the general population; the principal use of the flag in its early days was to represent ships and the diplomatic service of Japan abroad. (Naval vessels were granted a special version, with a smaller, off-centre sun from which rays extended prominently to the edges of the flag.) Specifications for the flag were issued in 1870. Because the Japanese have a deep philosophical approach to graphic designs of all kinds, they value their national flag for its simplicity, striking contrasts, and appropriate symbolism. The hot red of the sun symbol contrasts with its cool white background, and the circle of the sun contrasts with the rectangle of the flag itself. The pole on which it is to be officially hoisted is rough natural bamboo, while the finial at the top is a shiny gold ball. To regularize flag laws dating from the 19th century, the Diet (Japanese parliament) formally adopted the national flag on August 13, 1999. The national anthem (Kimigayo) was given official recognition at the same time. The Diet's action was a controversial one, supported in Japan by conservatives but denounced by pacifists, who argued that the symbols inappropriately recalled Japan's militaristic past and its involvement in World War II. Whitney Smith History Early modern Japan (15501850) Unification The Oda regime Important Japanese historical sites. In the 155060 period the Sengoku daimyo, who had survived the wars of the previous 100 years, moved into an even fiercer stage of mutual conflict. These powerful daimyo were harassed not only by each other but also by the rise of common people within their domains. The daimyo sought to resolve their dilemma by acquiring land and people to widen their domains and, finally, by trying to seize control of the whole country. That, of course, required the control of Kyoto, the political centre of Japan since ancient times. Out of these bloody struggles emerged one Sengoku daimyo, Oda Nobunaga of Owari province (in modern Aichi prefecture), who succeeded in occupying the capital as the first feudal unifier. The emergence of Nobunaga's regime reversed the feudal disintegration of the previous century and moved the country toward unification. Oda was a military genius, who was the first to successfully adapt firearms to Japanese warfare. His bold wars of suppression, waged against both other daimyo and recalcitrant religious communities, led to a great redrawing of the political map of Japan, previously split up among daimyo throughout the country. In the Kinai district, where Nobunaga's conquered territory was centred, however, he established control by dividing his new domain among his commanders. Rather than completely abrogating the long-established privileges of the temples, shrines, and local landlords (kokujin), he at first recognized them, regarding them as an important adjunct to the strengthening of his military power and using them as followers in his battles for unification. Cadastral surveys aimed at strengthening feudal landownership were at this stage carried out not so much to gain control over the complicated landholding and taxation system of the farmers as to define the size of fiefs (chigyo) of Nobunaga's retainers in order to confirm the extent of their military services and obligations to him. Nobunaga's unification policy was predicated on a separation of warriors from the farmers, but unification was hampered because of resistance from old political forces, especially several major Buddhist temples. Unification proceeded further during the era of Nobunaga's successor, Toyotomi Hideyoshi. The Hideyoshi regime Nobunaga's father was a minor Owari daimyo, whereas Hideyoshi was the son of a peasant from the same province. After entering Nobunaga's service, Hideyoshi impressed all with his brilliant talents, and he soon rose to become one of Nobunaga's most powerful commanders. After Nobunaga's deathhis vassal Akechi Mitsuhide assassinated himHideyoshi eliminated many rivals by relying on his superb political judgment and shrewd actions, firmly establishing himself as successor. Following in Nobunaga's footsteps, Hideyoshi proceeded to unify the whole country at a rapid pace, and by 1590 all Japanfrom Kyushu in the southwest to Tohoku in the northeasthad come under his control. As an example of Hideyoshi's shrewd judgment, he gave the Kanto domain, formerly controlled by the Hojo family, to Tokugawa Ieyasu, nominally as a reward for distinguished service. The reward forced Ieyasu to move to Edo (modern Tokyo); this was, in fact, a stratagem to remove the Tokugawa family from the Chubu region around modern-day Nagoya, which had been its power base. At the core of Hideyoshi's unification policy was its firm establishment in the principle of the separation between warriors and peasants. Hideyoshi adopted several major policies to accomplish this end: a comprehensive land survey (kenchi), the disarmament of the peasantry, and the separation of the classes. The so-called Taiko land survey played a crucial role in this process. Taiko was a traditional title for the former office of kampaku (chancellor) which Hideyoshi assumed in 1591. Like Nobunaga, Hideyoshi felt constrained by lineage not to make himself shogun and thus sought other titles to legitimize his rule. The Taiko land survey was carried out throughout the country from 1583 to 1598, being completed just before Hideyoshi's death. As a result of this survey, the complicated relationships of rights to landownership that had developed since the Kamakura period were now clarified. The former shoen system of complex landholding had been obliterated by Sengoku daimyo. Landowning relations were now based on kokudakai.e., on the actual product of the land. Moreover, this kokudaka now came within the landlord's grasp in every village, and land taxes were levied on the village as a unit. In addition to this definition of the rights held by the farming population, the kokudaka system also applied to the landholdings of the daimyo for distribution among their retainers. In place of previous land taxes (nengu) assessed in money as so many hundred or ten thousand kan of silver, an assessment of kokudaka was made as so many hundred or ten thousand koku of rice. A koku represented the amount of rice consumed by one person in one year (about five bushels); the amount also was used as a standard on which military services were levied in proportion. As part of the process, a register was drawn up in every village. Peasants had their rights as cultivators recognized to the extent that their land was duly registered; in return, they were bound to pay land taxes in rice and were forbidden to neglect the cultivation of their fields or to move elsewhere. In return for a certain security of tenure, peasants were thus tied more closely to the land, allowing for easier exploitation. The promulgation of an order of social-status control in 1591 prohibited warriors from taking up farming and forbade other daimyo from employing a samurai who left his master. The ordinance required that peasants remain in villages and not flee to cities; it also forbade artisans and merchants from residing in villages, thus extending Nobunaga's attempt to separate warriors and farmers into a social-class system of warriors, farmers, artisans, and merchants. Hideyoshi's so-called sword hunt (katana-gari) of 1588, which attempted to disarm the peasantry and melt the confiscated arms into an enormous statue of the Buddha, was an important prerequisite for this policy. With the establishment of the kokudaka system, the Taiko land survey delivered the final blow to the shoen system of manorial holdings, which had already virtually disappeared under the onslaught of the Sengoku daimyo. The feudal chigyo system, based on the kokudaka assessment, was established throughout the country. The provincial daimyo all submitted to Hideyoshi's regime, and the more egalitarian, alliance-like relationship between Nobunaga and the former Sengoku daimyo was replaced by a clear lord-vassal relationship. The political structure of the Hideyoshi regime was not yet fully sufficient, however, to be the unified governing authority for the whole country. For example, the kurairechi (lands under its direct control), which were the immediate financial base of the regime, amounted to more than 2.2 million koku by the time of Hideyoshi's death, nearly one-eighth of Japan's cultivated land. But aside from those in the metropolitan and surrounding provinces, these lands were in many cases divided among the distant, independent tozama (outside) daimyo, and the management of these lands was entrusted to them. Such lands were thus not firmly in the grasp of the regime. By contrast, the lands that later came under the direct control of the Tokugawa shogunate amounted to more than four million koku, or nearly double those of the Hideyoshi regime; four-fifths of these were managed by officials known as gundai and daikan, who were direct retainers of the shogunate, with only a fifth entrusted to daimyo. This limitation of Hideyoshi's regime gave rise to internal power struggles and finally drove Hideyoshi to such reckless actions as the invasions of Korea in 1592 and 1597. These two ill-advised adventures were designed to bring China under Hideyoshi's sway and to provide an outlet for tens of thousands of warlike samurai only recentlyand looselybrought under Hideyoshi's vassalage. Hideyoshi's regime collapsed on the failure of the second Korean expedition and as the direct result of Hideyoshi's subsequent death. Hideyoshi failed to bequeath his power to his heir, Hideyori, and Tokugawa Ieyasu emerged as the strongest candidate to succeed him. History Japan since 1850 The Meiji restoration Important Japanese historical sites. The term restoration is commonly applied to the political changes in Japan that returned power to the imperial house in 1868. In that year the boy emperor Mutsuhitolater known by his reign name Meiji, or Enlightened Rulereplaced the Tokugawa bakufu, or shogunate, at the political centre of the nation. Although phrased in traditional terms as a restoration of imperial rule, the changes initiated during the Meiji period (18681912) constituted a social and political revolution that began in the late Tokugawa period and was not completed until the promulgation of the Meiji constitution in 1889. The fall of the Tokugawa The arrival of Americans and Europeans in the 1850s increased domestic tensions. The bakufu, already weakened by an eroding economic base and ossified political structure, now found itself challenged by Western powers intent on opening Japan to trade and foreign intercourse. When the bakufu, despite opposition from the throne in Kyoto, signed the Treaty of Kanagawa (or Perry Convention; 1854) and the Harris treaty (1858), the shogun's claim of loyalty to the throne and his role as subduer of barbarians came to be questioned. To bolster his position, the shogun elicited support from the daimyo through consultation, only to discover that they were firmly xenophobic and called for the expulsion of Westerners. The growing influence of imperial loyalism, nurtured by years of peace and study, received support even within the shogunal camp from men such as Tokugawa Nariaki, the lord of Mito domain (han). Activists used the slogan Sonno joi (Revere the emperor! Expel the barbarians!) not only to support the throne but also to embarrass the bakufu. Nariaki and his followers sought to involve the Kyoto court directly in shogunal affairs in order to establish a nationwide program of preparedness. In this Nariaki was opposed by the bakufu's chief councillor (tairo), Ii Naosuke, who tried to steer the nation toward self-strengthening and gradual opening. But Ii's effort to restore the bakufu was short-lived. In the spring of 1860 he was assassinated by men from Mito and Satsuma. Ii's death inaugurated years of violence during which activist samurai used their swords against the hated barbarians and all who consorted with them. If swords proved of little use against Western guns, they exacted a heavy toll from political enemies. By the early 1860s the Tokugawa bakufu found itself in a dilemma. On the one hand it had to strengthen the country against foreigners. On the other it knew that providing the economic means for self-defense meant giving up shogunal controls that kept competing lords financially weak. Activist samurai, for their part, tried to push their feudal superiors into more strongly antiforeign positions. At the same time, antiforeign acts provoked stern countermeasures and diplomatic indemnities. Most samurai soon realized that expelling foreigners by force was impossible. Foreign military superiority was demonstrated conclusively with the bombardment of Kagoshima in 1863 and Shimonoseki in 1864. Thereafter, samurai activists used their antiforeign slogans primarily to obstruct and embarrass the bakufu, which retained little room to maneuver. Domestically it was forced to make antiforeign concessions to placate the loyalist camp, while foreigners were assured that it remained committed to opening the country and abiding by the treaties. Both sides saw it as prevaricating and ineffectual. After the arrival of the British minister Sir Harry Parkes in 1865, Great Britain, in particular, saw no reason to negotiate further with the bakufu and decided to deal directly with the imperial court in Kyoto. Samurai in several domains also revealed their dissatisfaction with the bakufu's management of national affairs. One domain in which the call for more direct action emerged was Choshu (now part of Yamaguchi prefecture), which fired on foreign shipping in the Shimonoseki Strait in 1863. This led to bombardment of Choshu's fortifications by Western ships in 1864 and a shogunal expedition that forced the domain to resubmit to Tokugawa authority. But many of Choshu's samurai refused to accept this decision, and a military coup in 1864 brought to power, as the daimyo's counselors, a group of men who had originally led the radical antiforeign movement. Several of these had secretly traveled to England and were consequently no longer blindly xenophobic. Their aims were nationalto overthrow the shogunate and create a new government headed by the emperor. The same men organized militia units that utilized Western training methods and arms and included nonsamurai troops. Choshu became the centre for discontented samurai from other domains who were impatient with their leaders' caution. In 1866 Choshu allied itself with neighbouring Satsuma, fearing a Tokugawa attempt to crush all opponents to create a centralized despotism with French help. Again shogunal armies were sent to control Choshu in 1866. The defeat of these troops by Choshu forces led to further loss of power and prestige. Meanwhile, the death of the shogun Iemochi in 1866 brought to power the last shogun, Yoshinobu, who realized the pressing need for national unity. In 1867 he resigned his powers rather than risk a full-scale military confrontation with Satsuma and Choshu, doing so in the belief that he would retain an important place in any emerging national administration. But this was not to be. Outmaneuvered by the young Meiji emperor, who succeeded to the throne in 1867, and a few court nobles who maintained close ties with Satsuma and Choshu, the shogun faced the choice of giving up his lands, which would risk revolt from his vassals, or appearing disobedient, which would justify punitive measures against him. Yoshinobu tried to move troops against Kyoto, only to be defeated. In the wake of this defeat, Satsuma, Choshu, and Tosa units, now the imperial army, advanced on Edo, which was surrendered without battle. While sporadic fighting continued until the summer of 1869, the Tokugawa cause was doomed. In January 1868 the principal daimyo were summoned to Kyoto to learn of the restoration of imperial rule. Later that year the emperor moved into the Tokugawa castle in Edo, and the city was renamed Tokyo (Eastern Capital). With the emperor and his supporters now in control, the building of the modern state began. History Ancient Japan to 1185 Prehistoric Japan Pre-Ceramic culture Important Japanese historical sites. It is not known when humans first settled on the Japanese archipelago. It was long believed that there was no Paleolithic occupation in Japan, but since World War II thousands of sites have been unearthed throughout the country, yielding a wide variety of Paleolithic tools. These include both core tools, made by chipping away the surface of a stone, and flake tools, made by working with a stone flake broken off from a larger piece of stone. There is little doubt that the people who used these implements moved to Japan from the Asian continent. At one stage, land connections via what are now the Korea and Tsushima straits made immigration from the Korean peninsula possible, while another connection, via what are now the Soya and Tsugaru straits, allowed people to come in from northeastern Asia. The Paleolithic Period in Japan is variously dated from 30,000 to 10,000 years ago, although the argument has been made for a Lower Paleolithic culture prior to 35,000 BC. Nothing certain is known of the culture of the period, though it seems likely that people lived by hunting and gathering, used fire, and made their homes either in pit-type dwellings or in caves. No bone or horn artifacts of the kind associated with this period in other areas of the world have yet been found in Japan. Since there was no knowledge whatsoever of pottery, the period is referred to as the Pre-Ceramic era. Climatic changes help to account for the existence of a Mesolithic stage in early Japanese culture, a time when much of the abundant fauna of earlier times became depleted by the expanding human population of the archipelago. The introduction of the bow and arrow is regarded as a local response to a decrease in game available for food. Jomon culture (7500 BC to c. 250 BC) The Pre-Ceramic era was followed by two better-recorded cultures, the Jomon and the Yayoi. The former takes its name from a type of pottery found throughout the archipelago; its discoverer, the 19th-century American zoologist Edward S. Morse, called the pottery jomon (cord marks) to describe the patterns pressed into the clay. A convincing theory dates the period during which Jomon pottery was used from about 10,000 years ago until the 2nd or 3rd century BC. Of the features common to Neolithic cultures throughout the worldprogress from chipped tools to polished tools, the manufacture of pottery, the beginnings of agriculture and pasturage, the development of weaving, and the erection of monuments using massive stonesthe first two are prominent features of the Jomon period, but the remaining three did not appear until the succeeding Yayoi period. Pottery, for example, first appeared in northern Kyushu (the southernmost of the four main Japanese islands) about 10,000 BC, in an era that is sometimes called the incipient Jomon period. While continental influence is suspected, the fact that Kyushu pottery remains predate any Chinese findings strongly suggests that the impetus to develop pottery was local. Jomon is thus best described as a Mesolithic culture, while Yayoi is fully Neolithic. The manufacture of pottery, however, was highly developed, and the work of Jomon peoples has a diversity and complexity of form and an exuberance of artistic decoration. It is customary to regard changes in pottery types as a basis for subdividing the age into six periods: incipient, very early, early, middle, late, and very late. Since Jomon culture spread over the entire archipelago, it also developed regional differences, and this combination of both chronological and regional variations gives the evolution of Jomon pottery a high degree of complexity. The pottery of the very early period includes many deep, urnlike vessels with tapered, bullet-shaped bases. In the early period the vessels of eastern Japan become roughly cylindrical in shape, with flat bases, and the walls contain an admixture of vegetable fibre. In the middle period there were rapid strides in pottery techniques; the pots produced during this time in the central mountain areas are generally considered to be the finest of the whole Jomon era. The surface of these normally cylindrical vessels is covered with complex patterns of raised lines, and powerfully decorative projections rise from the rim to form handles. From the middle period onward there is increasing variety in the types of vessels, and a clear distinction developed between high-quality ware using elaborate techniques and simpler pots made for purely practical use. The amount of the latter increases steadily, preparing the way for the transition to Yayoi pottery. Jomon dwelling sites have been found in various parts of the country. They can be classified into two types: one, the pit-type dwelling, consisted of a shallow pit with a floor of trodden earth and a roof; the other was made by laying a circular or oval floor of clay or stones on the surface of the ground and covering it with a roof. Remains of such dwellings have been found in groups ranging from five or six to several dozen, apparently representing the size of human settlements at the time. Most of these settlements form a horseshoe shape, with a space in the centre that seems to have been used for communal purposes. Nothing certain is known, however, concerning social or political organization at this period. It can be deduced that each household was made up of several family members and that the settlement made up of such households was led by a headman or shaman. The people of the Jomon period lived mainly by hunting and fishing and by gathering edible nuts and roots. The appearance of large settlements from the middle period onward has been interpreted by some scholars as implying the cultivation of certain types of cropa hypothesis seemingly supported by the fact that the chipped-stone axes of this period are not sharp but seem to have been used for digging soil. Doubtless there was some form of cultivation: starchy yams and taro, probably originating from the continent, were raised, the starch from them formed into a type of bread. This incipient agriculture seems related to a cultural florescence in mid-Jomon times that lasted about 1,000 years. Weaving was still unknown, and archaeological findings indicate that clothes were largely made of bark. Body ornamentation included bracelets made of seashells, earrings of stone or clay, and necklaces and hair ornaments of stone or bone and horn. From the latter part of the period, the custom also spread throughout the archipelago of extracting or pointing certain teeth, probably performed as a rite marking the attainment of adulthood. No especially elaborate rites of burial evolved, and the dead were buried in a small pit dug near the dwelling. Sometimes the body was buried with its knees drawn up or with a stone clasped to its chest, a procedure that probably had some religious or magical significance. A large number of clay figurines have been found, many representing female forms that were probably magical objects associated with primitive fertility cults. For years certain scholars have claimed that the bearers of the Jomon culture were not of Japanese ethnicity but were ancestors of the Ainu, an aboriginal people often regarded as having European (Caucasian) racial connections who now are found in northern Japan. Scientific investigation of the bones of Jomon people carried out since the beginning of the 20th century, however, has disproved this theory. The Jomon people might be called proto-Japanese, and they were spread throughout the archipelago. Despite certain variations in character arising from differences in period or place, they seem to have constituted a single ethnic stock with more or less consistent characteristics. The present Japanese people were produced by an admixture of certain strains from the Asian continent and from the South Pacific, together with adaptations made in accordance with environmental changes. Linguistic evidence suggests that a people speaking a language belonging to the Ural-Altaic family moved eastward across Siberia and entered Japan via Sakhalin Island and Hokkaido. Nothing can yet be proved concerning their relationship with the people of the Pre-Ceramic period, but it cannot be asserted that they were entirely unrelated. History Medieval Japan The Kamakura period (11851333) The establishment of warrior government The establishment of the bakufu by Minamoto Yoritomo at the end of the 12th century can be regarded as the beginning of a new era, one in which independent government by the warrior class successfully opposed the political authority of the civil aristocracy. Modern scholarly interpretation, however, has retreated from recognizing a major break and the establishment of feudal institutions with the founding of the Kamakura regime. During the Kamakura period, total warrior dominance was not achieved. There was, instead, what approached a dyarchy with civil power in Kyoto and military power in Kamakura sharing authority for governing the nation. Institutions of the Heian imperial-aristocratic system remained in place throughout the Kamakura age, replaced with new feudal institutions when Kamakura passed from the scene. During the Gempei War, Yoritomo established his headquarters in Kamakura and entrusted the suppression of the Taira to his younger brothers Noriyori and Yoshitsune. Meanwhile, he gathered a following of great eastern warrior leaders and began to lay the foundation for a new military government. In 1180, for example, Yoritomo set up the Samurai-dokoro (Board of Retainers), a disciplinary board to control his multiplying military vassals. General administration was handled by a secretariat, which was opened four years later and known as the Kumonjo (later renamed the Mandokoro). In addition, a judicial board, the Monchujo, was set up to handle lawsuits and appeals. These institutions represent the emergence of Yoritomo's regime (the term bakufu was used only later in retrospect). In 1185, after the destruction of the Taira family at the Battle of Dannoura, Yoritomo was granted the right to appoint his vassals, or gokenin (housemen) as military governors (shugo) in the provinces and military stewards (jito) in both public and private landed estates. It was the job of the shugo to recruit metropolitan guards and keep strict control over subversives and criminals. The jito collected taxes, supervised the management of landed estates, and maintained public order. Although the Gempei War ended in 1185, a dispute between Yoritomo and his brother Yoshitsune resulted in continued warfare until 1189, when Yoritomo finally destroyed the northern Fujiwara family of Mutsu province (modern Aomori prefecture), which had sheltered his rebellious brother. Three years later Yoritomo went to Kyoto and was appointed shogun (an abbreviation of seii taishogun; barbarian-quelling generalissimo), the highest honour that could be accorded a warrior. Though he kept the title only briefly and was not known by that term in the documents he issued to manage Kamakura affairs, shogun ultimately emerged as the title associated with the head of a bakufu. At first the chief base of the Kamakura bakufu lay in the shoen seized from the Taira family and in the limited administrative revenues from public estates in provinces granted to Yoritomo by the imperial court. But later the bakufu was able to expand its influence over lands that were still controlled by the civil provincial governors, as well as the private estates of the civil aristocracy and the temples and shrines. The Hojo regency Important Japanese historical sites. After the death of Yoritomo in 1199, real power in the bakufu passed into the hands of the Hojo family, from which Yoritomo's wife, Masako, had come. In 1203 Hojo Tokimasa, Masako's father, assumed the position of regent (shikken) for the shogun, an office that was held until 1333 by nine successive members of the Hojo family. Taking advantage of disputes among Yoritomo's generals, the Hojo overthrew and outmaneuvered their rivals, and after three generations the direct line of descent from Yoritomo had become extinct. Though wielding actual power, the Hojo family was of low social rank, and its leaders could not aspire to become shoguns themselves. Kujo Yoritsune, a Fujiwara scion and distant relative of Yoritomo, was appointed shogun, while Tokimasa's son Hojo Yoshitoki (shikken 120524) handled most government business. Thereafter, the appointment and dismissal of the shogun followed the wishes of the Hojo family. Shoguns were selected only from the Fujiwara or imperial houses, out of concern for pedigree. The increasing political power of the military led to a conflict with the aristocracy. Hence, the emperor Go-Toba, seeing in the demise of the Minamoto family a good opportunity to restore his political power, in 1221 issued a mandate to the country for the overthrow of Yoshitoki. Few warriors, however, responded to his call. Instead, the Hojo family dispatched a bakufu army that occupied Kyoto, and Go-Toba was arrested and banished to the island of Oki. This incident is known as the Jokyu Disturbance, named for the era name Jokyu (121922). The bakufu now set up a headquarters in Kyoto to supervise the court and to control the legal and administrative business of the western provinces. The several thousand estates of the civil aristocrats and warriors who had joined Go-Toba were confiscated, and Kamakura vassals were appointed to jito posts in them as rewards. The political power of the bakufu now extended over the whole country. Meanwhile, the regent Hojo Yasutoki, to strengthen the base of his political power, reorganized the council of leading retainers into a Council of State (Hyojo-shu). In 1232 the council drew up a legal code known as the Joei Formulary (Joei Shikimoku). Its 51 articles set down in writing for the first time the legal precedents of the bakufu. Its purpose was simpler than that of the ritsuryo, the old legal and political system of the Nara and Heian civil aristocracy. In essence, it was a body of pragmatic law laid down for the proper conduct of the warriors in administering justice. In 1249 the regent Hojo Tokiyori also set up a judicial court, the Hikitsuke-shu, to secure greater impartiality and promptness in legal decisions.