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Lullingstone Roman Villa

Lullingstone Roman Villa is a villa built during the Roman occupation of Britain, situated in Lullingstone near the village of Eynsford in Kent, south-eastern England. The villa is located in the Darent Valley, along with six others, including those at Crofton, Crayford and Dartford. Constructed in the 1st century, perhaps around 80–90 AD, the house was repeatedly expanded and occupied until it was destroyed by fire in the 4th or 5th century. The villa was occupied over various periods within the Romano-British period, but after its destruction, it is only thought to have been reoccupied during the medieval period. The occupants were most likely wealthy Romans or native Britons who had adopted Roman customs.

Some evidence found on site suggests that around 150 AD, the villa was considerably enlarged and may have been used as the country retreat of the governors of the Roman province of Britannia. Two sculpted marble busts found in the cellar may be those of Pertinax, governor in 185–186, and his father-in-law, Publius Helvius Successus. In the 4th century a room, probably already in religious use, was converted to a Christian chapel or house church, much the earliest known in the British Isles.

In the Anglo-Saxon period, the ruins of a Roman temple-mausoleum on the site of the villa were incorporated into a Christian chapel (Lullingstone Chapel) that was extant at the time of the Norman Conquest, one of the earliest known chapels in the country.

In addition to the pagan shrine in the villa's chapel and the dining room mosaics, the villa produced significant artistic finds including the Lullingstone Victory Gem and the busts.

Construction
The earliest part of the villa was built around 82 AD. It was situated in an area near to several other villas, and was close to Watling Street, a Roman road by which travellers could move to and from Londinium, Durobrivae, Durovernum Cantiacorum, and the major Roman port of Rutupiæ (i.e., London, Rochester, Canterbury, and Richborough, respectively).

Enlargement
Around 150 AD the villa was expanded and a heated bath block with hypocaust was added, but it was later rebuilt around 290 AD after being abandoned for almost a century.  Two marble busts from the 2nd century found in the cellar perhaps depict the owners or residents of the villa, which may have been the designated country retreat of the provincial governors. There is some evidence that the busts are those of Pertinax, governor of Britannia in 185–186 (and later Roman emperor), and his father.

In the 3rd century, a larger furnace for the hypocaust as well as an expanded bath block were added, as were a temple-mausoleum and a large granary. In the 4th century, the dining room was equipped with a fine mosaic floor with one illustration of Zeus or Jupiter, disguised as a bull, abducting Europa and a second depicting Bellerophon killing the Chimera.

Destruction and rediscovery
Sometime early in the 5th century, a fire destroyed the building, and it was abandoned and forgotten until its excavation in the 20th century.

The first discovery of the site was made in 1750, when workers fencing a deer park dug post holes through a mosaic floor. While the discovery and some additional evidence was noted, no further excavation took place. It wasn't until 1939 that the ruins of the villa were rediscovered by E. Greensfield and E. Birchenough when they noticed evidence of Roman walls and mosaic fragments beneath a blown-down tree. In the mid-20th century (1949–1961) the site was finally excavated by multiple teams of archaeologists. Until this first excavation, the villa and the rest of the Lullingstone ruins had remained untouched since its destruction. The ruins themselves were preserved under a specially designed cover in the 1960s, when the villa was taken over by English Heritage, who opened the ruins to the public. The building began to leak late in the 20th century and required a major £1.8m renovation and display project in 2006 to 2008 so artefacts from the Lullingstone site could be safely displayed within it.

In his excavation reports, Lieutenant-Colonel G. W. Meates covers the initial excavation of the site, including the discovery of the boundaries of the villa, coin and pottery evidence, and various rooms that were discovered. In the two earliest reports, Meates creates a rough timeline of the Lullingstone Villa ranging from the 1st century AD until the Post-Roman periods, including its purposes, room construction, abandonment, and its final destruction. In addition to the timeline and room descriptions, there are also detailed reports of the evidence found, such as pottery, coins, and soil and clay levels which indicate the time periods in which the villa is being observed.

1st century AD
During the original excavations of the site in the 1950s, evidence from various centuries was discovered, creating a timeline for the villa. The earliest evidence comes from the 1st century AD. Many shards of pottery were found on the slope that the excavation site was located on. The shards found are considered to be hand-made with elements of "Belgic culture".

2nd century AD: the Flavian to Antonine period
At the original excavation, the full extent of the house built and maintained during the Flavian dynasty to the Nerva-Antonine dynasty was unknown. However, it is thought that the Bath Room and the Basement Room may have been built during this era. From geological evidence, such as different layers of clay, it is suggested that the few stairs leading to the basement were built during this period rather than the 4th century AD, as originally thought.

3rd century AD
Based on pottery evidence, it is thought that the Lullingstone Roman Villa was abandoned for at least the first half of the 3rd century AD. Coins found at the site provide evidence that the occupation of the villa resumed sometime during the last half of the 3rd century during the reigns of Claudius II and Allectus. It is thought that the pagan shrine and other Christian rooms were constructed during this era after the period of abandonment. In addition to the Christian elements that were added to the villa, the 3rd century AD was also when some of the villa's main external buildings, including the granary and the temple, were constructed.

4th century AD
The 4th century was an eventful era for the villa, with large renovations taking place, and probably the fire. Some of the renovations of the villa include the designing of the mosaic floor in Room 5 and the construction of another room. Excavators were able to date the construction of the mosaic floor in Room 5 using coins depicting Constantine II that were accidentally mixed into the concrete.

Post-Roman period
At the initial excavation in the 1950s, there was no evidence that suggested occupation of the villa or its site from its destruction until at least medieval times. From English Heritage, there is documentation of some findings including a "hanging bowl" and other Anglo-Saxon potsherds. This evidence suggests that the site may have been used as a burial ground in early Anglo-Saxon Britain.

Rooms

Dining room
Rooms 12 and 13, previously known as Rooms 9 and 10, include the dining room, or triclinium, which was situated in the centre of the main building. As the largest room in the villa on the western side, it connected all other rooms to the north and south together via a large verandah. The dining room was highly decorated with a pair of large mosaics on the floor dating to the mid-4th century. One depicts the abduction of the princess Europa by the god Jupiter or Zeus who is disguised as a bull, whilst the other depicts Bellerophon slaying the Chimera, whilst surrounded by four sea creatures, including dolphins. In each of the four corners of the Bellerophon mosaic there is a bust of the seasons personified including winter, spring, summer, and autumn. Surrounding these mosaics were smaller images depicting hearts, crosses and swastikas. Even though these artworks are usually only seen as depictions of myth, it is also thought by some scholars that these works were meant to ward off the evil eye. Based on the artwork and the shape of the apse, it is thought that this room was also meant for entertaining. With the measurements of the apse being 6.25 metres by 4.88 metres at its largest points, the dining room was spacious, with potentially enough room to contain a couch. The couch, usually able to seat three people, would have been 1.5 metres to 2 metres in width, and directly facing the mosaic artwork so that it could be viewed in the correct orientation by all visitors.

Bath Wing
Thought to have been constructed in the Flavian–Antonine period, the Bath Wing was renovated and constantly used throughout the villa's existence. After the abandonment of the villa for almost a century, the Bath Wing was renovated, though the details of renovations are not mentioned. During the initial excavations, it was noted that the Bath Wing contained what G. W. Meates called a "combustion chamber". This chamber, filled with chalk, also shows evidence of burned charcoal that may have been used for heating.

Basement Room
During the original excavations of the site, it was thought that during its periods of use the Basement Room had multiple purposes, including as a garden room. It should also be noted that the term 'basement' cannot be interpreted to have the same meaning as the modern word. The walls of the room were highly decorated including orange, red, and green panels. Based on the archaeological and artistic evidence, the original height of the room is thought to have been 8 feet. When the villa was abandoned, the Basement Room was especially affected. Much of the walls and stairs were stripped of their materials, and were not replaced until the reoccupation of the villa. During the reoccupation, the walls of the Basement Room were redecorated and other details such as pottery were added. Partially destroyed by the fire, parts of the mosaic and the plaster from the room above fell into the Basement Room providing an abundance of intact evidence for the villa, which remained untouched until the beginning of the Lullingstone excavations in 1949'''. '''

Pagan shrine and Christian chapel
One room of the building had been used as both a pagan shrine and, later, as a Christian chapel, one of the earliest in Britain. Along with the Christian chapel, there were three or four other rooms that were also used for Christian purposes including a possible Antechamber and a Vestibule.

The original pagan shrine room was dedicated to local water deities, and a wall painting depicting three water nymphs dating from this period can still be seen in a niche in the room.

Just after the 3rd century, this niche had been covered over, as the whole room had been redecorated with white plaster painted with red bands, and two busts of male figures had been placed in the room. Some scholars have theorised that at this point the inhabitants focused their worship on household deities and ancestor spirits, largely abandoning the worship of the water deities.

In the 4th century the room above the pagan shrine was apparently converted to Christian use, with painted plaster on the walls, including a row of figures of standing worshipers (orans), and a characteristic Christian Chi-rho symbol. Some of the paintings are now on display in the British Museum.

According to English Heritage, which maintains the site: "The evidence of the Christian house-church is a unique discovery for Roman Britain and the wall paintings are of international importance. Not only do they provide some of the earliest evidence for Christianity in Britain, they are almost unique – the closest parallels come from a house-church in Dura Europus, Syria.

Perhaps almost as remarkable as the discovery of the house-church is the possibility that pagan worship may have continued in the cult room below. What is not clear is whether this represented the family hedging their bets, trumpeting their apparent acceptance of Christianity, while trying to keep the old gods happy, or whether it represents some members of the family clinging to old beliefs in the face of the adoption of Christianity by others."The overall purpose of the chapel other than worship is not certain, but it is thought that it was used for "liturgical worship" such as baptisms. Based on the fact that the Christian artwork was large in size, K. S. Painter suggests that the owners of the villa at this time were not only Christians, but also wealthy.

Graves
A Romano-Celtic temple-mausoleum complex was constructed around 300 AD to hold the bodies of two young people, those of a male and a female, in lead coffins. Although the young woman's coffin was robbed in antiquity, the other remained in situ and undisturbed, and is now on display at the site.

The Victory Gem
Discovered during the initial excavations by G.W. Meates, the Victory Gem is a "Roman cornelian intaglio". Cornelian intaglios like this were normally set in rings, and based on its size, it is thought that its ring was large. Measuring 23 by 19 by 5 mm, it is one of the largest gems ever found in Britain. Considering the potential size of the ring and other remnants of precious metals on the gem, such as gold, Martin Henig suggests that the ring was once owned by a man that held both high status and wealth. The gem depicts personified Victory writing a message of triumph on a shield. It is thought that the gem has Greek characteristics as the artwork depicts elements of the goddesses Nike and Aphrodite.

Busts
The two marble busts found in the Basement Room are thought to represent Pertinax, governor in 185–186 AD, and his father, Publius Helvius Successus. Some scholars suggest that these two busts provide insight into who occupied the villa in at least the 2nd century. One of the busts is thought to date to the Hadrianic period. Though they are both quite well preserved, the second, and larger of the busts was more damaged when it was found during the initial excavations. According to excavation reports, it is not entirely certain why they were placed in the Basement Room. It was noted, however, that after the period of abandonment, those who reoccupied the villa may have decided to keep them for their own purposes.

title: Lullingstone Roman Villa


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Four Horsemen of the Apocalypse (disambiguation)

The Four Horsemen of the Apocalypse are four beings described in the New Testament's Book of Revelation.

Four Horsemen of the Apocalypse or Four Horsemen may also refer to:

People

 * Four Horsemen (Supreme Court), United States Supreme Court's conservative justices during the New Deal era
 * Four Horsemen of the Apocalypse (blackjack), the four U.S. Army engineers who discovered in the 1950s the first correct Basic Strategy for the casino game of Blackjack
 * Four Horsemen (NASA), senior scientists and consultants to NASA during the Apollo program: Bob Walker, Jim Arnold, Paul Werner Gast, and Gerry Wasserburg
 * The Four Horsemen (discussion), a round table discussion by Richard Dawkins, Daniel C. Dennett, Sam Harris, and Christopher Hitchens
 * Four Horsemen (American football), the nickname of the 1924 Notre Dame Fighting Irish football team backfield
 * The Four Horsemen (professional wrestling), a professional wrestling stable
 * The Four Horseman, a contract bridge team founded in 1931 by P. Hal Sims, consisting of Sims, Oswald Jacoby, Willard S. Karn, and David Burnstine

Fiction

 * The Four Horsemen of the Apocalypse (novel), novel about the First World War by Vicente Blasco Ibáñez (1916)
 * The Four Horsemen (poetry), Toronto sound-poetry group formed by Steve McCaffery in 1970
 * Horsemen of Apocalypse, characters in Marvel's X-Men universe
 * Four Horsemen (Highlander), four immortals from Highlander: The Series
 * The Four Horsemen of the Apocalypse, lead characters in the East of West comic series by Jonathan Hickman and Nick Dragotta
 * Four Knights of the Apocalypse, Japanese manga series by Nakaba Suzuki
 * Four Horsemen (Chainsaw Man), a group of powerful devils in the Chainsaw Man manga series

Film and television

 * The Four Horsemen of the Apocalypse (film), a film based on the Blasco Ibáñez novel (1921)
 * The 4 Horsemen of the Apocalypse (film), remake of the 1921 film (1962)
 * Four of the Apocalypse, a spaghetti western (1975)
 * Four Horsemen (film), a documentary film by Ross Ashcroft on the banking system (2012)
 * Four Horsemen (Highlander), a group of Immortals on the television show Highlander: The Series
 * The Four Horsemen of the Apocalypse, characters in the 5th season of the TV series Supernatural
 * The Four Horsemen (professional wrestling), a former wrestling stable in the NWA and WCW wrestling organizations
 * The Four Horsemen, a fictitious group of 4 magicians in Now You See Me and its sequel

Bands

 * The Four Horsemen (band), a hard rock band from Hollywood (1989–1996)
 * The Four Horsemen (rap group), formed by Canibus, Killah Priest, Ras Kass, and Kurupt in 1996

Albums

 * Horsemen of the Apocalypse (album), Metallica demo
 * 4 Horsemen of the Apocalypse, an album by the Bollock Brothers (1985)
 * The Four Horsemen (album), by Ultramagnetic MC's (1993)

Songs

 * "The Four Horsemen (Aphrodite's Child song)", a song on the Aphrodite's Child album 666 (1972)
 * "Four Horsemen", a song on The Clash album London Calling (1979)
 * "The Four Horsemen" (Metallica song), on the Metallica album Kill 'Em All (1983)
 * "4 Horsemen of 2012", a song on the Klaxons EP Xan Valleys (2006)
 * "4 Horsemen", a song on the Timbaland album Textbook Timbo (2007)
 * "Four Horsemen of 2012", a song on the Klaxons album Myths of the Near Future (2007)
 * "The Four Horsemen", a song on the Judas Priest album Nostradamus (2008)
 * "The Four Horsemen", a song on the Rotting Christ album Rituals (2016)
 * "The Four Horseman", a song by Nebula from their album Transmission from Mothership Earth (2022)

Other uses

 * Four Horsemen Studios, a collectible figure design studio and manufacturer
 * The Four Horsemen of the Apocalypse (video game), a cancelled video game (2002)
 * The Four Horsemen of the Apocalypse, a woodcut by Albrecht Dürer in his series Apocalypse (1498)
 * Four Horsemen of the Apocalypse (painting), a painting by Russian artist Viktor Vasnetsov

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


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Stomach

The stomach is a muscular, hollow organ in the upper gastrointestinal tract of humans and many other animals, including several invertebrates. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach is involved in the gastric phase of digestion, following the cephalic phase in which the sight and smell of food and the act of chewing are stimuli. In the stomach a chemical breakdown of food takes place by means of secreted digestive enzymes and gastric acid.

The stomach is located between the esophagus and the small intestine. The pyloric sphincter controls the passage of partially digested food (chyme) from the stomach into the duodenum, the first and shortest part of the small intestine, where peristalsis takes over to move this through the rest of the intestines.

Structure
In the human digestive system, the stomach lies between the esophagus and the duodenum (the first part of the small intestine). It is in the left upper quadrant of the abdominal cavity. The top of the stomach lies against the diaphragm. Lying behind the stomach is the pancreas. A large double fold of visceral peritoneum called the greater omentum hangs down from the greater curvature of the stomach. Two sphincters keep the contents of the stomach contained; the lower esophageal sphincter (found in the cardiac region), at the junction of the esophagus and stomach, and the pyloric sphincter at the junction of the stomach with the duodenum.

The stomach is surrounded by parasympathetic (stimulant) and sympathetic (inhibitor) plexuses (networks of blood vessels and nerves in the anterior gastric, posterior, superior and inferior, celiac and myenteric), which regulate both the secretory activity of the stomach and the motor (motion) activity of its muscles.

The stomach is distensible, and can normally expand to hold about one litre of food. In a newborn human baby the stomach will only be able to hold about 30 millilitres. The maximum stomach volume in adults is between 2 and 4 litres. Although volumes of up to 15 L have been observed in extreme circumstances.

Sections

The human stomach can be divided into four sections, beginning at the cardia followed by the fundus, the body and the pylorus.
 * The gastric cardia is where the contents of the esophagus empty from the gastroesophageal sphincter into the cardiac orifice, the opening into the gastric cardia. A cardiac notch at the left of the cardiac orifice, marks the beginning of the greater curvature of the stomach. A horizontal line across from the cardiac notch gives the dome-shaped region called the fundus. The cardia is a very small region of the stomach that surrounds the esophageal opening.
 * The fundus is formed in the upper curved part.
 * The body or corpus is the main, central region of the stomach.
 * The pylorus opens to the body of the stomach. The pylorus connects the stomach to the duodenum at the pyloric sphincter.

The cardia is defined as the region following the "z-line" of the gastroesophageal junction, the point at which the epithelium changes from stratified squamous to columnar. Near the cardia is the lower esophageal sphincter.

Anatomical proximity
The stomach bed refers to the structures upon which the stomach rests in mammals. These include the tail of the pancreas, splenic artery, left kidney, left suprarenal gland, transverse colon and its mesocolon, and the left crus of diaphragm, and the left colic flexure. The term was introduced around 1896 by Philip Polson of the Catholic University School of Medicine, Dublin. However this was brought into disrepute by surgeon anatomist J Massey.

Blood supply

The lesser curvature of the human stomach is supplied by the right gastric artery inferiorly and the left gastric artery superiorly, which also supplies the cardiac region. The greater curvature is supplied by the right gastroepiploic artery inferiorly and the left gastroepiploic artery superiorly. The fundus of the stomach, and also the upper portion of the greater curvature, is supplied by the short gastric arteries, which arise from the splenic artery.

Lymphatic drainage
The two sets of gastric lymph nodes drain the stomach.

Wall

Like the other parts of the gastrointestinal wall, the human stomach wall from inner to outer, consists of a mucosa, submucosa, muscular layer, subserosa and serosa.

The inner part of the stomach wall is the gastric mucosa a mucous membrane that forms the lining of the stomach. the membrane consists of an outer layer of columnar epithelium, a lamina propria, and a thin layer of smooth muscle called the muscularis mucosa. Beneath the mucosa lies the submucosa, consisting of fibrous connective tissue. Meissner's plexus is in this layer interior to the oblique muscle layer.

Outside of the submucosa lies the muscular layer. It consists of three layers of muscular fibres, with fibres lying at angles to each other. These are the inner oblique, middle circular, and outer longitudinal layers. The presence of the inner oblique layer is distinct from other parts of the gastrointestinal tract, which do not possess this layer. The stomach contains the thickest muscular layer consisting of three layers, thus maximum peristalsis occurs here.
 * The inner oblique layer: This layer is responsible for creating the motion that churns and physically breaks down the food. It is the only layer of the three which is not seen in other parts of the digestive system. The antrum has thicker skin cells in its walls and performs more forceful contractions than the fundus.
 * The middle circular layer: At this layer, the pylorus is surrounded by a thick circular muscular wall, which is normally tonically constricted, forming a functional (if not anatomically discrete) pyloric sphincter, which controls the movement of chyme into the duodenum. This layer is concentric to the longitudinal axis of the stomach.
 * The myenteric plexus (Auerbach's plexus) is found between the outer longitudinal and the middle circular layer and is responsible for the innervation of both (causing peristalsis and mixing).

The outer longitudinal layer is responsible for moving the semi-digested food towards the pylorus of the stomach through muscular shortening.

To the outside of the muscular layer lies a serosa, consisting of layers of connective tissue continuous with the peritoneum.

Smooth mucosa along the inside of the lesser curvature forms a passageway - the gastric canal that fast-tracks liquids entering the stomach, to the pylorus.

Glands
The mucosa lining the stomach is lined with gastric pits, which receive gastric juice, secreted by between 2 and 7 gastric glands. Gastric juice is an acidic fluid containing hydrochloric acid and digestive enzymes. The glands contains a number of cells, with the function of the glands changing depending on their position within the stomach.

Within the body and fundus of the stomach lie the fundic glands. In general, these glands are lined by column-shaped cells that secrete a protective layer of mucus and bicarbonate. Additional cells present include parietal cells that secrete hydrochloric acid and intrinsic factor, chief cells that secrete pepsinogen (this is a precursor to pepsin- the highly acidic environment converts the pepsinogen to pepsin), and neuroendocrine cells that secrete serotonin.

Glands differ where the stomach meets the esophagus and near the pylorus. Near the gastroesophageal junction lie cardiac glands, which primarily secrete mucus. They are fewer in number than the other gastric glands and are more shallowly positioned in the mucosa. There are two kinds - either simple tubular glands with short ducts or compound racemose resembling the duodenal Brunner's glands. Near the pylorus lie pyloric glands located in the antrum of the pylorus. They secrete mucus, as well as gastrin produced by their G cells.

Gene and protein expression
About 20,000 protein-coding genes are expressed in human cells and nearly 70% of these genes are expressed in the normal stomach. Just over 150 of these genes are more specifically expressed in the stomach compared to other organs, with only some 20 genes being highly specific. The corresponding specific proteins expressed in stomach are mainly involved in creating a suitable environment for handling the digestion of food for uptake of nutrients. Highly stomach-specific proteins include gastrokine-1 expressed in the mucosa; pepsinogen and lipase, expressed in gastric chief cells; and a gastric ATPase and gastric intrinsic factor, expressed in parietal cells.

Development
In the early part of the development of the human embryo, the ventral part of the embryo abuts the yolk sac. During the third week of development, as the embryo grows, it begins to surround parts of the yolk sac. The enveloped portions form the basis for the adult gastrointestinal tract. The sac is surrounded by a network of vitelline arteries and veins. Over time, these arteries consolidate into the three main arteries that supply the developing gastrointestinal tract: the celiac artery, superior mesenteric artery, and inferior mesenteric artery. The areas supplied by these arteries are used to define the foregut, midgut, and hindgut. The surrounded sac becomes the primitive gut. Sections of this gut begin to differentiate into the organs of the gastrointestinal tract, and the esophagus, and stomach form from the foregut.

As the stomach rotates during early development, the dorsal and ventral mesentery rotate with it; this rotation produces a space anterior to the expanding stomach called the greater sac, and a space posterior to the stomach called the lesser sac. After this rotation the dorsal mesentery thins and forms the greater omentum, which is attached to the greater curvature of the stomach. The ventral mesentery forms the lesser omentum, and is attached to the developing liver. In the adult, these connective structures of omentum and mesentery form the peritoneum, and act as an insulating and protective layer while also supplying organs with blood and lymph vessels as well as nerves. Arterial supply to all these structures is from the celiac trunk, and venous drainage is by the portal venous system. Lymph from these organs is drained to the prevertebral celiac nodes at the origin of the celiac artery from the aorta.

Digestion
In the human digestive system, a bolus (a small rounded mass of chewed up food) enters the stomach through the esophagus via the lower esophageal sphincter. The stomach releases proteases (protein-digesting enzymes such as pepsin), and hydrochloric acid, which kills or inhibits bacteria and provides the acidic pH of 2 for the proteases to work. Food is churned by the stomach through peristaltic muscular contractions of the wall – reducing the volume of the bolus, before looping around the fundus and the body of stomach as the boluses are converted into chyme (partially digested food). Chyme slowly passes through the pyloric sphincter and into the duodenum of the small intestine, where the extraction of nutrients begins.

Gastric juice in the stomach also contains pepsinogen. Hydrochloric acid activates this inactive form of enzyme into the active form, pepsin. Pepsin breaks down proteins into polypeptides.

Mechanical digestion
Within a few moments after food enters the stomach, mixing waves begin to occur at intervals of approximately 20 seconds. A mixing wave is a unique type of peristalsis that mixes and softens the food with gastric juices to create chyme. The initial mixing waves are relatively gentle, but these are followed by more intense waves, starting at the body of the stomach and increasing in force as they reach the pylorus.

The pylorus, which holds around 30 mL of chyme, acts as a filter, permitting only liquids and small food particles to pass through the mostly, but not fully, closed pyloric sphincter. In a process called gastric emptying, rhythmic mixing waves force about 3 mL of chyme at a time through the pyloric sphincter and into the duodenum. Release of a greater amount of chyme at one time would overwhelm the capacity of the small intestine to handle it. The rest of the chyme is pushed back into the body of the stomach, where it continues mixing. This process is repeated when the next mixing waves force more chyme into the duodenum.

Gastric emptying is regulated by both the stomach and the duodenum. The presence of chyme in the duodenum activates receptors that inhibit gastric secretion. This prevents additional chyme from being released by the stomach before the duodenum is ready to process it.

Chemical digestion
The fundus stores both undigested food and gases that are released during the process of chemical digestion. Food may sit in the fundus of the stomach for a while before being mixed with the chyme. While the food is in the fundus, the digestive activities of salivary amylase continue until the food begins mixing with the acidic chyme. Ultimately, mixing waves incorporate this food with the chyme, the acidity of which inactivates salivary amylase and activates lingual lipase. Lingual lipase then begins breaking down triglycerides into free fatty acids, and mono- and diglycerides.

The breakdown of protein begins in the stomach through the actions of hydrochloric acid, and the enzyme pepsin.

The contents of the stomach are completely emptied into the duodenum within two to four hours after the meal is eaten. Different types of food take different amounts of time to process. Foods heavy in carbohydrates empty fastest, followed by high-protein foods. Meals with a high triglyceride content remain in the stomach the longest. Since enzymes in the small intestine digest fats slowly, food can stay in the stomach for 6 hours or longer when the duodenum is processing fatty chyme. However, this is still a fraction of the 24 to 72 hours that full digestion typically takes from start to finish.

Absorption
Although the absorption in the human digestive system is mainly a function of the small intestine, some absorption of certain small molecules nevertheless does occur in the stomach through its lining. This includes:
 * Water, if the body is dehydrated
 * Medication, such as aspirin
 * Amino acids
 * 10–20% of ingested ethanol (e.g. from alcoholic beverages)
 * Caffeine
 * To a small extent water-soluble vitamins (most are absorbed in the small intestine)

The parietal cells of the human stomach are responsible for producing intrinsic factor, which is necessary for the absorption of vitamin B12. B12 is used in cellular metabolism and is necessary for the production of red blood cells, and the functioning of the nervous system.

Control of secretion and motility

Chyme from the stomach is slowly released into the duodenum through coordinated peristalsis and opening of the pyloric sphincter. The movement and the flow of chemicals into the stomach are controlled by both the autonomic nervous system and by the various digestive hormones of the digestive system:

Other than gastrin, these hormones all act to turn off the stomach action. This is in response to food products in the liver and gall bladder, which have not yet been absorbed. The stomach needs to push food into the small intestine only when the intestine is not busy. While the intestine is full and still digesting food, the stomach acts as storage for food.

Other
Epidermal growth factor (EGF) results in cellular proliferation, differentiation, and survival. EGF is a low-molecular-weight polypeptide first purified from the mouse submandibular gland, but since then found in many human tissues including the submandibular gland, and the parotid gland. Salivary EGF, which also seems to be regulated by dietary inorganic iodine, also plays an important physiological role in the maintenance of oro-esophageal and gastric tissue integrity. The biological effects of salivary EGF include healing of oral and gastroesophageal ulcers, inhibition of gastric acid secretion, stimulation of DNA synthesis, and mucosal protection from intraluminal injurious factors such as gastric acid, bile acids, pepsin, and trypsin and from physical, chemical, and bacterial agents.
 * Effects of EGF

The human stomach has receptors responsive to sodium glutamate and this information is passed to the lateral hypothalamus and limbic system in the brain as a palatability signal through the vagus nerve. The stomach can also sense, independently of tongue and oral taste receptors, glucose, carbohydrates, proteins, and fats. This allows the brain to link nutritional value of foods to their tastes.
 * Stomach as nutrition sensor

This syndrome defines the association between thyroid disease and chronic gastritis, which was first described in the 1960s. This term was coined also to indicate the presence of thyroid autoantibodies or autoimmune thyroid disease in patients with pernicious anemia, a late clinical stage of atrophic gastritis. In 1993, a more complete investigation on the stomach and thyroid was published, reporting that the thyroid is, embryogenetically and phylogenetically, derived from a primitive stomach, and that the thyroid cells, such as primitive gastroenteric cells, migrated and specialized in uptake of iodide and in storage and elaboration of iodine compounds during vertebrate evolution. In fact, the stomach and thyroid share iodine-concentrating ability and many morphological and functional similarities, such as cell polarity and apical microvilli, similar organ-specific antigens and associated autoimmune diseases, secretion of glycoproteins (thyroglobulin and mucin) and peptide hormones, the digesting and readsorbing ability, and lastly, similar ability to form iodotyrosines by peroxidase activity, where iodide acts as an electron donor in the presence of H2O2. In the following years, many researchers published reviews about this syndrome.
 * Thyrogastric syndrome

Diseases
A series of radiographs can be used to examine the stomach for various disorders. This will often include the use of a barium swallow. Another method of examination of the stomach, is the use of an endoscope. A gastric emptying study is considered the gold standard to assess the gastric emptying rate.

A large number of studies have indicated that most cases of peptic ulcers, and gastritis, in humans are caused by Helicobacter pylori infection, and an association has been seen with the development of stomach cancer.

A stomach rumble is actually noise from the intestines.

Surgery
In humans, many bariatric surgery procedures involve the stomach, in order to lose weight. A gastric band may be placed around the cardia area, which can adjust to limit intake. The anatomy of the stomach may be modified, or the stomach may be bypassed entirely.

Surgical removal of the stomach is called a gastrectomy, and removal of the cardia area is a called a cardiectomy. "Cardiectomy" is a term that is also used to describe the removal of the heart. A gastrectomy may be carried out because of gastric cancer or severe perforation of the stomach wall.

Fundoplication is stomach surgery in which the fundus is wrapped around the lower esophagus and stitched into place. It is used to treat gastroesophageal reflux disease (GERD).

Etymology
The word stomach is derived from Greek stomachos (στόμαχος), ultimately from stoma (στόμα) 'mouth'. Gastro- and gastric (meaning 'related to the stomach') are both derived from Greek gaster (γαστήρ) 'belly'.

Other animals
Although the precise shape and size of the stomach varies widely among different vertebrates, the relative positions of the esophageal and duodenal openings remain relatively constant. As a result, the organ always curves somewhat to the left before curving back to meet the pyloric sphincter. However, lampreys, hagfishes, chimaeras, lungfishes, and some teleost fish have no stomach at all, with the esophagus opening directly into the intestine. These animals all consume diets that require little storage of food, no predigestion with gastric juices, or both.

The gastric lining is usually divided into two regions, an anterior portion lined by fundic glands and a posterior portion lined with pyloric glands. Cardiac glands are unique to mammals, and even then are absent in a number of species. The distributions of these glands vary between species, and do not always correspond with the same regions as in humans. Furthermore, in many non-human mammals, a portion of the stomach anterior to the cardiac glands is lined with epithelium essentially identical to that of the esophagus. Ruminants, in particular, have a complex stomach, the first three chambers of which are all lined with esophageal mucosa.

In birds and crocodilians, the stomach is divided into two regions. Anteriorly is a narrow tubular region, the proventriculus, lined by fundic glands, and connecting the true stomach to the crop. Beyond lies the powerful muscular gizzard, lined by pyloric glands, and, in some species, containing stones that the animal swallows to help grind up food.

In insects, there is also a crop. The insect stomach is called the midgut.

Information about the stomach in echinoderms or molluscs can be found under the respective articles.

title: Stomach