The Parthian Empire

The Parthian Empire Traditionally, the Parthian Empire (Arsacid Empire) lasted from 247 B.C. – A.D. 224. The starting date is the time of which the Parthians occupied the satrapy of the Seleucid Empire known as Parthia (modern Turkmenistan). The end date marks the start of the Sassanid Empire. The founder of the Parthian Empire is said to have been Arsaces of the tribe of the Parni (a semi-nomadic steppe people), for which reason the Parthian era is also referred to as the Arsacid. There is a debate over the founding date. The high date sets the founding between 261 and 246 B.C., while the low date sets the founding between c. 240/39 and c. 237 B.C. The Extent of the Empire While the Parthian Empire started as the Parthian satrapy, it expanded and diversified. Eventually, it extended from the Euphrates to the Indus Rivers, covering Iran, Iraq, and most of Afghanistan. Although it came to embrace most of the territory occupied by the Seleucid monarchs, the Parthians never conquered Syria. The capital of the Parthian Empire was originally Arsak, but it later moved to Ctesiphon. A Sassanid prince from Fars (Persis, in southern Iran), rebelled against the last Parthian king, the Arsacid Artabanus V, thereby starting the Sassanid era. Parthian Literature In Looking East from the Classical World: Colonialism, Culture, and Trade from Alexander the Great to Shapur I, Fergus Millar says that no literature in an Iranian language survives from the entire Parthian period. He adds that there is documentation from the Parthian period, but its scanty and mostly in Greek. Government The government of the Parthian Empire has been described as an unstable, decentralized political system, but also a step in the direction of the first highly integrated, bureaucratically complex empires in Southwest Asia [Wenke]. It was, for much of its existence, a coalition of vassal states with tense relationships among rival ethnic groups. It was also subject to outside pressure from Kushans, Arabs, Romans, and others. Sources Josef Wiesehà ¶fer Parthia, Parthian empire The Oxford Companion to Classical Civilization. Ed. Simon Hornblower and Antony Spawforth. Oxford University Press, 1998. Elymeans, Parthians, and the Evolution of Empires in Southwestern Iran, Robert J. Wenke; Journal of the American Oriental Society (1981), pp. 303-315. Looking East from the Classical World: Colonialism, Culture, and Trade from Alexander the Great to Shapur I, by Fergus Millar; The International History Review (1998), pp. 507-531. The Date of the Secession of Parthia from the Seleucid Kingdom, by Kai Brodersen; Historia: Zeitschrift fà ¼r Alte Geschichte (1986), pp. 378-381

10 Interesting Facts About Mercury (Element)

10 Interesting Facts About Mercury (Element) Mercury is a shiny, silvery liquid metal, sometimes called quicksilver. It is a transition metal with atomic number 80 on the periodic table, atomic weight of 200.59, and  the element symbol Hg.  Here are some fast facts plus 10 interesting element facts about mercury. You can find even more detailed information on the mercury facts page. Fast Facts: The Element Mercury Element Name: MercuryElement Symbol: HgAtomic Number: 80Atomic Weight: 200.592Classification: Transition Metal or Post-Transition MetalState of Matter: LiquidName Origin: The symbol Hg comes from the name hydrargyrum, which means water-silver. The name mercury comes from the Roman god Mercury, known for his swiftness.Discovered By: Known before 2000 BCE in China and India Mercury is the only metal that is a liquid at standard temperature and pressure.  The only other liquid element under standard conditions is bromine (a halogen), although  the metals rubidium, cesium, and gallium melt just warmer than room temperature.  Mercury has a very high surface tension, so it forms rounded  beads of liquid.Although mercury and all of its compounds are  known to be highly toxic, it was considered therapeutic throughout much of history.The modern element symbol for mercury is Hg, which is the symbol for another name for mercury: hydrargyrum. Hydrargyrum comes from Greek words for water-silver (hydr- means water, argyros means silver).Mercury is a very rare element in the Earths crust. It accounts for only about only 0.08 parts per million (ppm).  It is mainly found in the mineral cinnabar, which is mercuric sulfide. Mercuric sulfide is the source  of the red pigment called vermilion.Mercury generally is not allowed on aircraft because it combines s o readily with aluminum, a metal that is common on aircraft. When mercury forms an amalgam with aluminum, the oxide layer that protects aluminum from oxidizing is disrupted. This causes aluminum to corrode, in much the same way as iron rusts. Mercury does not react with most acids.Mercury is a relatively poor conductor of heat. Most metals are excellent thermal conductors.  It is a mild electrical conductor. The freezing point  (-38.8 degrees Celsius) and boiling point (356 degrees Celsius) of mercury are closer together than for any other metals.Although mercury usually exhibits a 1 or 2 oxidation state, sometimes it has a 4 oxidation state.  The electron configuration causes mercury to behave somewhat like a noble gas. Like noble gases, mercury forms relatively weak chemical bonds with other elements. It forms amalgams with all the other metals, except for iron. This makes iron a good choice to make containers to hold and transport mercury.The element Mercury is named for the Roman god Mercury. Mercury is the only element to retain its alchemical name as its modern common name.  The element was known to ancient civilizations, dating back to at least 2000 BCE Vials of pure mercury have been found in Egyptian tomb s from the 1500s BCE. Mercury is used in fluorescent lamps, thermometers, float valves, dental amalgams, in medicine, for the production of other chemicals, and to make liquid mirrors. Mercury(II) fulminate is an explosive used as a primer in firearms. The disinfectant mercury compound thimerosal is an organomercury compound found in vaccines, tattoo inks, contact lens solutions, and cosmetics.   Sources Lide, D.R., editor. Handbook of Chemistry and Physics. 86th edition, CRC Press, 2005, pp.  4.125–4.126.Meija, J., et al. Atomic Weights of the Elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry, vol. 88, no. 3, 2016, pp. 265–91.Weast, R.C., editor.  Handbook of Chemistry and Physics. 64th edition, CRC Press, 1984, p.  E110.