California is the most populous state in the United States and the third most extensive by area. Located on the western coast of the U. S, California is bordered by the other U. S. states of Oregon and Arizona and shares an international border with the Mexican state of Baja California. Los Angeles is Californias most populous city, and the second largest after New York City. The Los Angeles Area and the San Francisco Bay Area are the nations second- and fifth-most populous urban regions, California has the nations most populous county, Los Angeles County, and its largest county by area, San Bernardino County. The Central Valley, an agricultural area, dominates the states center. What is now California was first settled by various Native American tribes before being explored by a number of European expeditions during the 16th and 17th centuries, the Spanish Empire claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its war for independence.
The western portion of Alta California was organized as the State of California, the California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom. If it were a country, California would be the 6th largest economy in the world, fifty-eight percent of the states economy is centered on finance, real estate services and professional, scientific and technical business services. Although it accounts for only 1.5 percent of the states economy, the story of Calafia is recorded in a 1510 work The Adventures of Esplandián, written as a sequel to Amadis de Gaula by Spanish adventure writer Garci Rodríguez de Montalvo. The kingdom of Queen Calafia, according to Montalvo, was said to be a land inhabited by griffins and other strange beasts. This conventional wisdom that California was an island, with maps drawn to reflect this belief, shortened forms of the states name include CA, Cal. Calif. and US-CA.
Settled by successive waves of arrivals during the last 10,000 years, various estimates of the native population range from 100,000 to 300,000. The Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups were diverse in their organization with bands, villages. Trade and military alliances fostered many social and economic relationships among the diverse groups, the first European effort to explore the coast as far north as the Russian River was a Spanish sailing expedition, led by Portuguese captain Juan Rodríguez Cabrillo, in 1542. Some 37 years English explorer Francis Drake explored and claimed a portion of the California coast in 1579. Spanish traders made unintended visits with the Manila galleons on their trips from the Philippines beginning in 1565
Sandstone is a clastic sedimentary rock composed mainly of sand-sized minerals or rock grains. Most sandstone is composed of quartz or feldspar because these are the most common minerals in the Earths crust, like sand, sandstone may be any color, but the most common colors are tan, yellow, grey, pink and black. Since sandstone beds often form highly visible cliffs and other topographic features, quartz-bearing sandstone is converted into quartzite through heating and pressure, usually related to tectonic compression within orogenic belts. They are formed from cemented grains that may either be fragments of a rock or be mono-minerallic crystals. The cements binding these grains together are typically calcite, grain sizes in sands are defined within the range of 0.0625 mm to 2 mm. The formation of sandstone involves two principal stages, first, a layer or layers of sand accumulates as the result of sedimentation, either from water or from air. Typically, sedimentation occurs by the settling out from suspension.
The most common cementing materials are silica and calcium carbonate, which are derived either from dissolution or from alteration of the sand after it was buried. Colours will usually be tan or yellow, a predominant additional colourant in the southwestern United States is iron oxide, which imparts reddish tints ranging from pink to dark red, with additional manganese imparting a purplish hue. Red sandstones are seen in the Southwest and West of Britain, as well as central Europe. The regularity of the latter favours use as a source for masonry, either as a building material or as a facing stone. These physical properties allow the grains to survive multiple recycling events. Quartz grains evolve from rock, which are felsic in origin. Feldspathic framework grains are commonly the second most abundant mineral in sandstones, Feldspar can be divided into two smaller subdivisions, alkali feldspars and plagioclase feldspars. The different types of feldspar can be distinguished under a petrographic microscope, below is a description of the different types of feldspar.
Alkali feldspar is a group of minerals in which the composition of the mineral can range from KAlSi3O8 to NaAlSi3O8. Plagioclase feldspar is a group of solid solution minerals that range in composition from NaAlSi3O8 to CaAl2Si2O8. Lithic framework grains are pieces of ancient source rock that have yet to weather away to individual mineral grains, accessory minerals are all other mineral grains in a sandstone, commonly these minerals make up just a small percentage of the grains in a sandstone
New England is a geographical region comprising six states of the northeast United States, Maine, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York to the west and south, the Atlantic Ocean is to the east and southeast, and Long Island Sound is to the south. Its largest metropolitan area is Greater Boston, which includes Worcester, ten years later, more Puritans settled north of Plymouth Colony in Boston, thus forming Massachusetts Bay Colony. Over the next 126 years, people in the region fought in four French and Indian Wars, until the British and their Iroquois allies defeated the French and their Algonquin allies in North America. In 1692, the town of Salem and surrounding areas experienced one of the most infamous cases of hysteria in the history of the Western Hemisphere. The Boston Tea Party was a protest to which Britain responded with a series of punitive laws stripping Massachusetts of self-government, the confrontation led to the first battles of the American Revolutionary War in 1775, and the expulsion of the British authorities from the region in spring 1776.
Each state is subdivided into small incorporated municipalities known as towns. The only unincorporated areas in the region exist in the populated northern regions of Vermont, New Hampshire. The region is one of the U. S. Census Bureaus nine regional divisions, the earliest known inhabitants of New England were American Indians who spoke a variety of the Eastern Algonquian languages. Prominent tribes included the Abenaki, Penobscot, Mohegans, Narragansett Indians, prior to the arrival of Europeans, the Western Abenakis inhabited New Hampshire, New York, and Vermont, as well as parts of Quebec and western Maine. Their principal town was Norridgewock in present-day Maine, the Penobscot lived along the Penobscot River in Maine. The Narragansett and smaller tribes under Narragansett sovereignty lived in most of modern-day Rhode Island, west of Narragansett Bay, the Wampanoag occupied southeastern Massachusetts, Rhode Island, and the islands of Marthas Vineyard and Nantucket. The Pocumtucks lived in Western Massachusetts, and the Mohegan and Pequot tribes in the Connecticut region, the Connecticut River Valley includes parts of Vermont, New Hampshire and Connecticut, and linked different indigenous communities culturally and politically.
As early as 1600, French and English traders began exploring the New World, trading metal, glass, on April 10,1606, King James I of England issued a charter for each of the Virginia Companies and Plymouth. These were privately funded ventures, intended to land for England, conduct trade. In 1620, Plymouth in present-day Massachusetts was settled by Pilgrims from the Mayflower, in 1616, English explorer John Smith named the region New England. As the first colonists arrived in Plymouth, they wrote and signed the Mayflower Compact, the Massachusetts Bay Colony came to dominate the area and was established by royal charter in 1629 with its major town and port of Boston established in 1630. Massachusetts Puritans began to settle in Connecticut as early as 1633, roger Williams was banished from Massachusetts for heresy, led a group south, and founded Providence Plantation in the area that became the Colony of Rhode Island and Providence Plantations in 1636
North Conway, New Hampshire
North Conway is a census-designated place and village in eastern Carroll County, New Hampshire, United States. The population was 2,349 at the 2010 census, a year-round resort area, North Conway is the largest village within the town of Conway, which is bounded on the east by the Maine state line. The White Mountain National Forest is to the west and north, Conway is home to Cathedral Ledge, Echo Lake State Park, and Mount Cranmore. North Conway is known for its number of outlet shops. Early settlers called the area Pequawket, adopting the name of the Abenaki Indian village which stretched down the Saco River to its center at Fryeburg. North Conway is in the White Mountains, with Mount Washington to the northwest, the rugged terrain became popular in the 19th century with artists. In 1874, the built an Second Empire depot, designed by Nathaniel J. Bradlee. In 1932, snow trains began carrying enthusiasts to the birthplace of American skiing, increasing automobile travel brought the decline of trains.
The railroad, part of the Boston & Maine, abandoned passenger service to the area in 1961, the Conway Scenic Railroad was established. Today, the line offers visitors a tour of the region, the station is listed on the National Register of Historic Places. In the late 1980s, the White Mountain Airport closed and was redeveloped as an outlet mall called Settlers Green Outlet Village. Continued growth through the 1990s and 2000s in North Conway and the villages nearby made Conway the most populous community in Carroll County, a bypass of the area is being developed. North Conway remains a destination due to its shopping, recreation. North Conway and its surrounding towns offer hiking in the White Mountain National Forest, the area is a major rock climbing destination in the northeastern United States, particularly Cathedral Ledge in Echo Lake State Park. The 500-foot cliff overlooks Echo Lake and North Conway from the west, unlike nearby White Horse Ledge, another rock climbing site, Cathedral Ledge has an automobile road to the summit, which provides fine views of the Saco River Valley.
In late September through early October, tourists arrive to see the colors on the surrounding mountains. The Conway Scenic Railroad features train rides that leave from the villages Victorian station, North Conway is located at 44°3′6″N 71°7′22″W, in the northern part of the town of Conway. North Conway is drained by the Saco River, as of the census of 2010, there were 2,349 people,1,105 households, and 547 families residing in the CDP
Mount Kilimanjaro, with its three volcanic cones, Kibo and Shira, is a dormant volcano in Tanzania. It is the highest mountain in Africa, and rises approximately 4,900 m from its base to 5,895 metres above sea level, the first recorded ascent to the summit of the mountain was by Hans Meyer and Ludwig Purtscheller in 1889. The mountain is part of the Kilimanjaro National Park and is a major climbing destination, the mountain has been the subject of many scientific studies because of its shrinking glaciers. Kilimanjaro rises approximately 4,900 m from its base in the plains near the municipality of Moshi to its summit height of 5,895 metres. Kilimanjaro is the highest volcano outside South America, Kilimanjaro is a large stratovolcano and is composed of three distinct volcanic cones, the highest, Mawenzi at 5,149 metres, and Shira, the shortest at 4,005 metres. Mawenzi and Shira are extinct, while Kibo is dormant and could erupt again, Uhuru Peak is the highest summit on Kibos crater rim. The Tanzania National Parks Authority, a Tanzanian governmental agency, and that height is based on a British Ordnance Survey in 1952.
Since then, the height has been measured as 5,892 metres in 1999,5,891 metres in 2008, the interior of the volcanic edifice is poorly known, given the lack of large scale erosion that could have exposed the interiors of the volcano. Shira is topped by a plateau at 3,800 metres. The remnant caldera rim has been degraded deeply by erosion, before the caldera formed and erosion began, Shira might have been between 4,900 m and 5,200 m high. It is mostly composed of lavas with some pyroclastics. The formation of the caldera was accompanied by lava emanating from ring fractures, two cones formed subsequently, the phonolitic one at the northwest end of the ridge and the doleritic Platzkegel in the caldera centre. Both Mawenzi and Kibo began erupting about 1 million years ago and they are separated by the Saddle Plateau at 4,400 metres elevation. The youngest dated rocks at Mawenzi are about 448,000 years old, Mawenzi forms a horseshoe shaped ridge with pinnacles and ridges opening to the northeast which has a tower like shape resulting from deep erosion and a mafic dyke swarm.
Several large cirques cut into the ring, the largest of these sits on top of the Great Barranco gorge, notable are the Ost and West Barrancos on the northeastern side of the mountain. Most of the side of the mountain has been removed by erosion. Mawenzi has a peak named Neumann Tower. Kibo is the largest cone and is more than 15 miles wide at the Saddle Plateau altitude, the last activity here has been dated to between 150,000 and 200,000 years ago and created the current Kibo summit crater
The Antarctic Peter I Island and the sub-Antarctic Bouvet Island are dependent territories and thus not considered part of the Kingdom. Norway lays claim to a section of Antarctica known as Queen Maud Land, until 1814, the kingdom included the Faroe Islands and Iceland. It included Isle of Man until 1266, Shetland and Orkney until 1468, Norway has a total area of 385,252 square kilometres and a population of 5,258,317. The country shares a long border with Sweden. Norway is bordered by Finland and Russia to the north-east, Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. King Harald V of the Dano-German House of Glücksburg is the current King of Norway, erna Solberg became Prime Minister in 2013, replacing Jens Stoltenberg. A constitutional monarchy, Norway divides state power between the Parliament, the Cabinet and the Supreme Court, as determined by the 1814 Constitution, the kingdom is established as a merger of several petty kingdoms. By the traditional count from the year 872, the kingdom has existed continuously for 1,144 years, Norway has both administrative and political subdivisions on two levels and municipalities.
The Sámi people have an amount of self-determination and influence over traditional territories through the Sámi Parliament. Norway maintains close ties with the European Union and the United States, the country maintains a combination of market economy and a Nordic welfare model with universal health care and a comprehensive social security system. Norway has extensive reserves of petroleum, natural gas, lumber, the petroleum industry accounts for around a quarter of the countrys gross domestic product. On a per-capita basis, Norway is the worlds largest producer of oil, the country has the fourth-highest per capita income in the world on the World Bank and IMF lists. On the CIAs GDP per capita list which includes territories and some regions, from 2001 to 2006, and again from 2009 to 2017, Norway had the highest Human Development Index ranking in the world. It has the highest inequality-adjusted ranking, Norway ranks first on the World Happiness Report, the OECD Better Life Index, the Index of Public Integrity and the Democracy Index.
Norway has two names, Noreg in Nynorsk and Norge in Bokmål. The name Norway comes from the Old English word Norðrveg mentioned in 880, meaning way or way leading to the north. In contrasting with suðrvegar southern way for Germany, and austrvegr eastern way for the Baltic, the Anglo-Saxon of Britain referred to the kingdom of Norway in 880 as Norðmanna land. This was the area of Harald Fairhair, the first king of Norway, and because of him
East Germany, formally the German Democratic Republic, was an Eastern Bloc state during the Cold War period. The Soviet zone surrounded West Berlin, but did not include it, as a result, the German Democratic Republic was established in the Soviet Zone, while the Federal Republic was established in the three western zones. East Germany, which lies culturally in Central Germany, was a state of the Soviet Union. Soviet occupation authorities began transferring administrative responsibility to German communist leaders in 1948, Soviet forces, remained in the country throughout the Cold War. Until 1989, the GDR was governed by the Socialist Unity Party, though other parties participated in its alliance organisation. The economy was centrally planned, and increasingly state-owned, prices of basic goods and services were set by central government planners, rather than rising and falling through supply and demand. Although the GDR had to pay war reparations to the USSR. Nonetheless it did not match the growth of West Germany.
Emigration to the West was a significant problem—as many of the emigrants were well-educated young people, the government fortified its western borders and, in 1961, built the Berlin Wall. Many people attempting to flee were killed by guards or booby traps. In 1989, numerous social and political forces in the GDR and abroad led to the fall of the Berlin Wall, the following year open elections were held, and international negotiations led to the signing of the Final Settlement treaty on the status and borders of Germany. The GDR was dissolved and Germany was unified on 3 October 1990, the GDR bordered the Soviet sector of Allied-occupied Berlin known as East Berlin which was administered as the states de facto capital. It bordered the three sectors occupied by the United States, United Kingdom and France known collectively as West Berlin. The three sectors occupied by the Western nations were sealed off from the rest of the GDR by the Berlin Wall from its construction in 1961 until it was brought down in 1989, the official name was Deutsche Demokratische Republik, usually abbreviated to DDR.
West Germans, the media and statesmen purposely avoided the official name and its abbreviation, instead using terms like Ostzone, Sowjetische Besatzungszone. The centre of power in East Berlin was referred to as Pankow. Over time, the abbreviation DDR was used colloquially by West Germans. However, this use was not always consistent, for example, before World War II, Ostdeutschland was used to describe all the territories east of the Elbe, as reflected in the works of sociologist Max Weber and political theorist Carl Schmitt
Mount Wellington (Tasmania)
Mount Wellington, officially known as kunanyi / Mount Wellington, is a mountain in the southeast coastal region of Tasmania, Australia. The mountain is the summit of the Wellington Range on whose foothills is built much of the city of Hobart, there is a sealed narrow road to the summit, about 22 kilometres from Hobart central business district. An enclosed lookout near the summit provides views of the city below and to the east, the Derwent estuary. From Hobart, the most distinctive feature of Mount Wellington is the cliff of dolerite columns known as the Organ Pipes and it has extensive views of Hobart and is one of the citys biggest tourist destinations. The low-lying areas and foothills of Mount Wellington were formed by slow geological upsurge when the whole Hobart area was a low-lying cold shallow seabed and it is often incorrectly considered to be a dormant volcano. Mount Wellington was originally referred by the original Tasmanian nations of the area as Unghbanyahletta, the Palawa, the surviving descendants of the original indigenous Tasmanians, tend to prefer the latter name.
In 2013, a Tasmanian dual naming policy was announced and Kunanyi / Mount Wellington was named as one of the inaugural dual named geographic features. In 1793 Commodore John Hayes arrived at the Derwent River, naming the mountain Skiddaw, after the mountain in the Lake District, in 1798 Matthew Flinders and George Bass circumnavigated the island. Bruni dEntrecasteauxs men were the first European to sail up the river, Nicholas Baudin led another French expedition in 1802, and whilst sheltering in the Derwent River Baudin referred to the mountain as ‘Montagne du Plateau’. However, the British first settled in the Hobart area in 1804, in February 1836, Charles Darwin visited Hobart Town and climbed Mount Wellington. In his book The Voyage of the Beagle, Darwin described the mountain thus, in many parts the Eucalypti grew to a great size, and composed a noble forest. The fronds forming the most elegant parasols, produced a gloomy shade, the summit of the mountain is broad and flat, and is composed of huge angular masses of naked greenstone.
Its elevation is 3,100 feet above the level of the sea, the first weather station was set up on Mount Wellington in 1895 by Clement Lindley Wragge. Mount Wellington has played host to some notorious characters over time, especially the bushranger Rocky Whelan, the cave where he lived is known appropriately as Rocky Whelans Cave, and is an easy walk from the Springs. Throughout the 19th and into the 20th centuries, the Mountain was a popular day-resort for residents of Hobart, to that end, many excursion huts were built over the lower slopes of the mountain. Sadly, many of the more remote huts have suffered from vandalism, the road to the summit was constructed in the early 1930s as a relief scheme for the unemployed, an idea initiated by Albert Ogilvie, the Premier of Tasmania of the day. Today the trees have grown again but the scar most people see today is not actually the road but a line of rocks with no trees 50–100 m above the road. The road itself was opened in August 1937, after two years of work, by Governor Sir Ernest Clark
Scotland is a country that is part of the United Kingdom and covers the northern third of the island of Great Britain. It shares a border with England to the south, and is surrounded by the Atlantic Ocean, with the North Sea to the east. In addition to the mainland, the country is made up of more than 790 islands, including the Northern Isles, the Kingdom of Scotland emerged as an independent sovereign state in the Early Middle Ages and continued to exist until 1707. By inheritance in 1603, James VI, King of Scots, became King of England and King of Ireland, Scotland subsequently entered into a political union with the Kingdom of England on 1 May 1707 to create the new Kingdom of Great Britain. The union created a new Parliament of Great Britain, which succeeded both the Parliament of Scotland and the Parliament of England. Within Scotland, the monarchy of the United Kingdom has continued to use a variety of styles, the legal system within Scotland has remained separate from those of England and Wales and Northern Ireland, Scotland constitutes a distinct jurisdiction in both public and private law.
Glasgow, Scotlands largest city, was one of the worlds leading industrial cities. Other major urban areas are Aberdeen and Dundee, Scottish waters consist of a large sector of the North Atlantic and the North Sea, containing the largest oil reserves in the European Union. This has given Aberdeen, the third-largest city in Scotland, the title of Europes oil capital, following a referendum in 1997, a Scottish Parliament was re-established, in the form of a devolved unicameral legislature comprising 129 members, having authority over many areas of domestic policy. Scotland is represented in the UK Parliament by 59 MPs and in the European Parliament by 6 MEPs, Scotland is a member nation of the British–Irish Council, and the British–Irish Parliamentary Assembly. Scotland comes from Scoti, the Latin name for the Gaels, the Late Latin word Scotia was initially used to refer to Ireland. By the 11th century at the latest, Scotia was being used to refer to Scotland north of the River Forth, alongside Albania or Albany, the use of the words Scots and Scotland to encompass all of what is now Scotland became common in the Late Middle Ages.
Repeated glaciations, which covered the land mass of modern Scotland. It is believed the first post-glacial groups of hunter-gatherers arrived in Scotland around 12,800 years ago, the groups of settlers began building the first known permanent houses on Scottish soil around 9,500 years ago, and the first villages around 6,000 years ago. The well-preserved village of Skara Brae on the mainland of Orkney dates from this period and it contains the remains of an early Bronze Age ruler laid out on white quartz pebbles and birch bark. It was discovered for the first time that early Bronze Age people placed flowers in their graves, in the winter of 1850, a severe storm hit Scotland, causing widespread damage and over 200 deaths. In the Bay of Skaill, the storm stripped the earth from a large irregular knoll, when the storm cleared, local villagers found the outline of a village, consisting of a number of small houses without roofs. William Watt of Skaill, the laird, began an amateur excavation of the site, but after uncovering four houses
It is bordered by the Atlantic Ocean to the east, the states of Connecticut and Rhode Island to the south, New Hampshire and Vermont to the north, and New York to the west. The state is named for the Massachusett tribe, which inhabited the area. The capital of Massachusetts and the most populous city in New England is Boston, over 80% of Massachusetts population lives in the Greater Boston metropolitan area, a region influential upon American history and industry. Originally dependent on agriculture and trade, Massachusetts was transformed into a manufacturing center during the Industrial Revolution, during the 20th century, Massachusetts economy shifted from manufacturing to services. Modern Massachusetts is a leader in biotechnology, higher education, finance. Plymouth was the site of the first colony in New England, founded in 1620 by the Pilgrims, in 1692, the town of Salem and surrounding areas experienced one of Americas most infamous cases of mass hysteria, the Salem witch trials. In 1777, General Henry Knox founded the Springfield Armory, which during the Industrial Revolution catalyzed numerous important technological advances, in 1786, Shays Rebellion, a populist revolt led by disaffected American Revolutionary War veterans, influenced the United States Constitutional Convention.
In the 18th century, the Protestant First Great Awakening, which swept the Atlantic World, in the late 18th century, Boston became known as the Cradle of Liberty for the agitation there that led to the American Revolution. The entire Commonwealth of Massachusetts has played a commercial and cultural role in the history of the United States. Before the American Civil War, Massachusetts was a center for the abolitionist, temperance, in the late 19th century, the sports of basketball and volleyball were invented in the western Massachusetts cities of Springfield and Holyoke, respectively. Many prominent American political dynasties have hailed from the state, including the Adams, both Harvard University and the Massachusetts Institute of Technology, in Cambridge, have been ranked among the most highly regarded academic institutions in the world. Massachusetts public school students place among the top nations in the world in academic performance, the official name of the state is the Commonwealth of Massachusetts.
While this designation is part of the official name, it has no practical implications. Massachusetts has the position and powers within the United States as other states. Massachusetts was originally inhabited by tribes of the Algonquian language family such as the Wampanoag, Nipmuc, Pocomtuc and Massachusett. While cultivation of crops like squash and corn supplemented their diets, villages consisted of lodges called wigwams as well as longhouses, and tribes were led by male or female elders known as sachems. Between 1617 and 1619, smallpox killed approximately 90% of the Massachusetts Bay Native Americans, the first English settlers in Massachusetts, the Pilgrims, arrived via the Mayflower at Plymouth in 1620, and developed friendly relations with the native Wampanoag people. This was the second successful permanent English colony in the part of North America that became the United States, the event known as the First Thanksgiving was celebrated by the Pilgrims after their first harvest in the New World which lasted for three days
Nylon is a generic designation for a family of synthetic polymers, more specifically aliphatic or semi-aromatic polyamides. They can be melt-processed into fibers, films or shapes, the first example of nylon was produced on February 28,1935, by Wallace Carothers at DuPonts research facility at the DuPont Experimental Station. Nylon polymers have significant commercial applications in fibers, in shapes. Nylon is made of repeating units linked by bonds and is a type of polyamide and is frequently referred to as such. Nylon was the first commercially successful synthetic thermoplastic polymer, nylon polymer is made by reacting monomers which are either lactams, acid/amines or stoichiometric mixtures of diamines and diacids. Mixtures of these can be polymerized together to make copolymers, Nylon polymers can be mixed with a wide variety of additives to achieve many different property variations. Nylon was invented accidentally by Julian W. Hill, a chemist for DuPont under Wallace Carotherss supervision and it was only given this name at the 1939 New York Worlds Fair.
The patents were owned by DuPont, Nylon was intended to be a synthetic replacement for silk and substituted for it in many different products after silk became scarce during World War II. It replaced silk in military applications such as parachutes and flak vests, after initial commercialization of nylon as a fiber, applications in the form of shapes and films were developed. The main market for nylon shapes now is in auto components, in 1940, John W. Eckelberry of DuPont stated that the letters nyl were arbitrary and the on was copied from the suffixes of other fibers such as cotton and rayon. A publication by DuPont explained that the name was intended to be No-Run. Since the products were not really run-proof, the vowels were swapped to produce nuron, for clarity in pronunciation, the i was changed to y. Most nylons are made from the reaction of an acid with a diamine or a lactam or amino acid with itself. In the first case, the structure is so-called ABAB similar to polyesters and polyurethanes, in the second case, the repeating unit corresponds to the single monomer.
It is difficult to get the proportions exactly correct, and deviations can lead to termination at molecular weights less than a desirable 10,000 daltons. To overcome this problem, a crystalline, solid nylon salt can be formed at room temperature, using an exact 1,1 ratio of the acid, the salt is crystallized to purify it and obtain the desired precise stoichiometry. Heated to 285 °C, the salt reacts to form nylon polymer with the production of water, Wallace Carothers at DuPont patented nylon 66, but overlooked the possibility to use lactams. That synthetic route was developed by Paul Schlack at IG Farben, leading to nylon 6, the peptide bond within the caprolactam is broken with the exposed active groups on each side being incorporated into two new bonds as the monomer becomes part of the polymer backbone
Aid climbing is a style of climbing in which standing on or pulling oneself up via devices attached to fixed or placed protection is used to make upward progress. In general, aid techniques are reserved for pitches where free climbing is difficult to impossible, while aid climbing places less emphasis on athletic fitness and raw strength than free climbing, the physical demands of hard aid climbing should not be underestimated. Aid climbing has its own ranking system, using a scale from A0 through A5. Just as in climbing, the usual aid technique involves two climbers, a leader and a belayer. The leader is connected by a rope to the belayer, who remains at the station while the leader moves up. As the leader advances, the rope is let out by the belayer, if the leader falls, the belayer locks off the rope and, assuming the protection doesnt pull out, catches the leaders fall on the rope. When the leader, moving up, reaches the end of the rope, or a convenient stopping point, he or she builds an anchor, hangs on it and this becomes the next belay station.
The belayer ascends the rope using mechanical ascenders, retrieving the protection that was placed by the leader. Many variations on this technique are possible, including solo aid climbing and climbing with a team of three or more. Until the 1940s protection was provided by the piton, driven into a crack in the rock with a hammer, aid climbing uses a considerably larger array of hardware than the pitons used by the first climbers although the primary technique of ascension has not much evolved. The typical gear of an aid climber includes pitons, copperheads, camming devices, hauling pulleys, daisy chains, the hardest aid routes are poorly protected requiring the climber to make long sequences of moves using hooks or tenuous placements. On these routes, a climber may have to commit to moving up onto the most marginal of placements risking long and sometimes dangerous falls. By contrast, the vast majority of aid ascents are done on popular free climbs which are too difficult for the aid party to free, but offer excellent gear placements.
Since aid climbing is extremely slow compared to climbing, this can lead to some conflicts between aid climbers and free climbers waiting to climb a route. There is additional tension caused by the damage that aid climbing often does to routes, hooks frequently break or otherwise damage holds that human hands and feet do not. Until the 1960s or so, aid climbing was normal practice in most climbing areas, reinhold Messner wrote, Rock faces are no longer overcome by climbing skill, but are humbled, pitch by pitch, by methodical manual labour … Who has polluted the pure spring of mountaineering. Free climbing is now the mainstream of climbing, the solution is often a compromise in which an absolute minimum of bolts is added to allow safe protection for free climbers, while not totally destroying the challenge of the route as an aid climb. However, as with most compromises, this is not a solution that satisfies everyone, the A grading scale incorporates difficulty of placing protection, and the danger associated with falling