Like Mecca, the city of Medina only permits Muslims to enter. The "haram" (area closed to non-Muslims) of Medina is much smaller than that of Mecca, though. Many facilities on the outskirts of Medina are open to non-Muslims. In Mecca the area closed to non-Muslims extends well beyond the limits of the built-up area. Both cities' numerous mosques are the destination for large numbers of Muslims on their annual pilgrimage. Hundreds of thousands of Muslims come to Medina each year to visit the 'Tomb of Prophet' and to worship at mosques in a unified celebration. Muslims believe that praying once in the Mosque of the Prophet is equal to praying at least 1000 times in any other mosque.
Doctrine
Doctrine (Latin: "doctrina") is a code of beliefs or "a body of teachings".
Doctrine often means several religious dogmas that a church teaches.
But it can also mean a principle of law, in the common law traditions, established through a history of past decisions, such as the doctrine of self-defense, or the principle of fair use.
In matters of foreign policy, a doctrine, also known as dogma, is group of fundamental rules for a nation's foreign policy. Examples include the Monroe Doctrine, the Stimson Doctrine, the Truman Doctrine, the Eisenhower Doctrine, the Nixon Doctrine, the Brezhnev Doctrine, the Kirkpatrick doctrine, and the Bush Doctrine.
Examples of religious doctrines include:
One department of the Roman Curia is called the Congregation for the Doctrine of the Faith.
The term also applies to the concept of an established procedure to a complex operation in warfare. The typical example is tactical doctrine in which a standard set of maneuvers, kinds of troops and weapons are employed as a default approach to a kind of attack.
Examples of military doctrines include:
Citron
The citron ("Citrus medica") is a species of citrus fruit. It usually has a thick rind and small sections. Originally, the tree came from Southeast Asia. Today it is mainly grown in Sicily, Morocco, Crete, and Corsica, as well as Puerto Rico. The tree can grow to a size of about 3 metres. The fruit can grow to a size of about 25 cm in length, and about 4 kg in weight. The pulp of the fruit is hardly ever used. The rind is used. It is made into an additive for cooking. Jam can also be made from the rind. The rind is also used to make vegetable oil, which is used for perfumes.
Generally, it is eaten preserved or in bakery goods, such as fruitcakes. (The candied peel rather than the fruit is often used in cooking.) In some cultures, it is made into a fruity tea. Pliny the Elder states that in his time , the citron could only be grown in Media and Persia ("HN" xii.7). The Romans tried to transport it into the Roman Empire in tightly packed pots, but failed, according to Pliny. There is evidence, however, which shows it was cultivated in the Mediterranean during Pliny's lifetime. Zohary and Hopf believe this tree was first domesticated in India. They think that its wild forms, along with those of the mandarin and pomelo, were the original citrus species.
The citron has many names in different countries; one popular reference is "Cedrat", which is the French name for the fruit. Theophrastus referred to the citron as the Persian or Median Apple, and the fruit later came to be known as the Citrus Apple. Pliny calls the tree the Assyrian, or the Median, "apple" (the generic Greco-Roman name for globose fruits). Other citrus crops were not introduced to the Mediterranean basin until Islamic times.
In many languages other than English, a normal lemon is called a "citron" and a Lime is called a "limon". Although the East Asian citrus fruit "yuzu" (also called "yuja") is sometimes called a citron, it is actually a separate species, "Citrus junos".
The citron fruit is slow-growing. The citron tree is typically grown from cuttings that are two to four years old; the tree begins to bear fruit when it is around three years old. The fruit is oblong in shape, and sometimes as much as six inches in length. Its skin is thick, somewhat hard, fragrant, and covered with protuberances; the pulp is white and subacid.
In Pliny's time the fruit was never eaten (it began to be used in cooking by the early 2nd century), but its intense perfume was used, penetrating clothes to repel noxious insects (compare Citronella).
In Hebrew, the citron is known as the etrog (). It is one of the Four Species used during the holiday of Sukkot each fall. The role of the citron in that holiday was portrayed in the Israeli movie Ushpizin. Citrons that have been bred with lemon (in order to increase output per tree and make the tree less fragile) are not kosher for use as part of the Four Species.
In South Indian cuisine, especially Tamil cuisine, citron is widely used in pickles and preserves. In Tamil, the unripe fruit is referred to as 'narthangai', which is usually salted and dried to make a preserve. The tender leaves of the plant are often used in conjunction with chili powder and other spices to make a powder, called 'narthellai podi', literally translating to 'powder of citron leaves'. Both narthangai and narthellai podi are usually consumed with 'thayir sadam' (Curd Rice - Yogurt Rice).
In Korea, it is used to create a syrupy tea (called Yuja cha) where the slices of whole fruit are eaten with the sweet tea. The fruit is thinly sliced (peel, pith and pulp) and soaked or cooked in honey or sugar to create a chunky syrup. This syrupy candied fruit is mixed with hot water as a fragrant tea, where the fruit at the bottom of the cup is eaten as well. Often perserved in the syrup for the cold months, Yuja tea served as a source of fruit in winter. It is also popular in Taiwan, where it is known as 柚子茶 (Youzi cha).
[Note: The Korean Yuja is the same as the Japanese Yuzu 柚子 and must be different from the citron being described in this article. The Japanese Yuzu = Citrus junos.]
Citric acid
Citric acid is a weak organic acid. It can be found in citrus fruits ( like oranges). It is used by organisms for Krebs cycle. It acts like a preservative when added to food. It is also used to add a sour (acidic) taste to foods and soft drinks. In the European Union it is known as E 330, as a food additive.
Carl Wilhelm Scheele was the first who could extract citric acid from lemons, in 1782. The substance was probably known to alchemists, perhaps with a different name. The Arabian alchemist Geber is said to have discovered citric acid in the 9th century. Citric Acid contains 6 Carbon atoms, 8 Hydrogen atoms and 7 Oxygen atoms. Its chemical formula is CHO.
Geber
Jābir ibn Ḥayyān (; ; died between 806 and 816), is the name for the writer of a great number of writings in Arabic. The writings together have the name Jabirian corpus. The most important subjects of these writings are: alchemy, cosmology, numerology, astrology, medicine, magic, mysticism, and philosophy.
Jabir's writings have in them the oldest known list of chemical substances. For the first time, the writings gave an explanation of how to produce an inorganic substance (ammonium chloride) from organic substances (such as plants, blood, and hair).
Modern scholars doubt the historical existence of Jabir. It is probable that one person did not write all of the writings in the Jabirian corpus. Instead, scholars see Jabir ibn Hayyan as a pseudonym that a group of writers used.
Translations into Latin of some of Jabir's Arabic writings (like the "Book of Mercy", and the "Book of Seventy") came into existence in the Middle Ages. In Latin, Jabir had the name "Geber", a transliteration of "Jabir".
In 13th-century Europe an anonymous writer, called pseudo-Geber, started to produce new writings about alchemy under the name Geber. People still read the in the 17th century. The "" was one of the writings that pseudo-Geber produced in the 13th century. It was an influence on early modern chemists like Robert Boyle (1627–1691).
Carl Wilhelm Scheele