A steamship referred to as a steamer, is a type of steam powered vessel ocean-faring and seaworthy, propelled by one or more steam engines that move propellers or paddlewheels. The first steamships came into practical usage during the early 1800s. Steamships use the prefix designations of "PS" for paddle steamer or "SS" for screw steamer; as paddle steamers became less common, "SS" is assumed by many to stand for "steam ship". Ships powered by internal combustion engines use a prefix such as "MV" for motor vessel, so it is not correct to use "SS" for most modern vessels; as steamships were less dependent on wind patterns, new trade routes opened up. The steamship has been described as a "major driver of the first wave of trade globalization" and contributor to "an increase in international trade, unprecedented in human history." The steamship was preceded by smaller vessels designed for insular transportation, called steamboats. Once the technology of steam was mastered at this level, steam engines were mounted on larger, ocean-going vessels.
Becoming reliable, propelled by screw rather than paddlewheels, the technology changed the design of ships for faster, more economic propulsion. Paddlewheels as the main motive source became standard on these early vessels, it was an effective means of propulsion under ideal conditions but otherwise had serious drawbacks. The paddle-wheel performed best when it operated at a certain depth, however when the depth of the ship changed from added weight it further submerged the paddle wheel causing a substantial decrease in performance. Within a few decades of the development of the river and canal steamboat, the first steamships began to cross the Atlantic Ocean; the first sea-going steamboat was an ex-French lugger. The first iron steamship to go to sea was the 116-ton Aaron Manby, built in 1821 by Aaron Manby at the Horseley Ironworks, became the first iron-built vessel to put to sea when she crossed the English Channel in 1822, arriving in Paris on 22 June, she carried passengers and freight to Paris in 1822 at an average speed of 8 knots.
The American ship SS Savannah first crossed the Atlantic Ocean, although most of the voyage was made under sail. The first ship to make the transatlantic trip under steam power may have been the British-built Dutch-owned Curaçao, a wooden 438 ton vessel built in Dover and powered by two 50 hp engines, which crossed from Hellevoetsluis, near Rotterdam on 26 April 1827 to Paramaribo, Surinam on 24 May, spending 11 days under steam on the way out and more on the return. Another claimant is the Canadian ship SS Royal William in 1833; the first steamship purpose-built for scheduled trans-Atlantic crossings was the British side-wheel paddle steamer SS Great Western built by Isambard Kingdom Brunel in 1838, which inaugurated the era of the trans-Atlantic ocean liner. The SS Archimedes, built in Britain in 1839 by Francis Pettit Smith, was the world's first screw propeller-driven steamship for open water seagoing, it had considerable influence on ship development, encouraging the adoption of screw propulsion by the Royal Navy, in addition to her influence on commercial vessels.
The first screw-driven propeller steamship introduced in America was on a ship built by Thomas Clyde in 1844 and many more ships and routes followed. The key innovation that made ocean-going steamers viable was the change from the paddle-wheel to the screw-propeller as the mechanism of propulsion; these steamships became more popular, because the propeller's efficiency was consistent regardless of the depth at which it operated. Being smaller in size and mass and being submerged, it was far less prone to damage. James Watt of Scotland is given credit for applying the first screw propeller to an engine at his Birmingham works, an early steam engine, beginning the use of a hydrodynamic screw for propulsion; the development of screw propulsion relied on the following technological innovations. Steam engines had to be designed with the power delivered at the bottom of the machinery, to give direct drive to the propeller shaft. A paddle steamer's engines drive a shaft, positioned above the waterline, with the cylinders positioned below the shaft.
SS Great Britain used chain drive to transmit power from a paddler's engine to the propeller shaft - the result of a late design change to propeller propulsion. An effective stern tube and associated bearings were required; the stern tube contains the propeller shaft. It should provide an unrestricted delivery of power by the propeller shaft; the combination of hull and stern tube must avoid any flexing that will bend the shaft or cause uneven wear. The inboard end has a stuffing box; some early stern tubes were made of brass and operated as a water lubricated bearing along the entire length. In other instances a long bush of soft metal was fitted in the after end of the stern tube; the Great Eastern had this arrangement fail on her first transatlantic voyage, with large amounts of uneven wear. The problem was solved with a lignum vitae water-lubricated bearing, patented in 1858; this is in use today. Since the motive power of screw propulsion is delivered along the shaft, a thrust bearing is needed to transfer that load to the hull without excessive friction.
SS Great Britain had a 2 ft diameter gunmetal plate on the forward end of the shaft which bore against a steel plate attached to the engine beds. Water
Drevsjø is a village in Engerdal municipality, Norway, taking its name from the Drevsjø, the lake near which it stands. Drevsjø is well known for its fishing opportunities, it is only 60 minutes from one of Scandinavia's biggest alpine centres, Trysilfjellet. It is the site of the Blokkodden Villmarksmuseum, an open-air museum presenting the history of the use of the natural world since the 18th century. Since 1990 it has had a reception centre for asylum seekers in Norway. Drevsjø has a subarctic climate with only 3 months with a mean exceeding 10. There is a wetter period from a dry period from December to April. Store Norske Lekison: Drevsjø
Hedmark is a county in Norway, bordering Trøndelag to the north, Oppland to the west and Akershus to the south. The county administration is in Hamar. Hedmark makes up the northeastern part of the southeastern part of the country, it has a long border with Dalarna County and Värmland County. The largest lakes are the largest lake in Norway. Parts of Glomma, Norway's longest river, flow through Hedmark. Geographically, Hedmark is traditionally divided into: Hedemarken, east of Mjøsa, Østerdalen, north of Elverum, Glåmdalen, south of Elverum. Hedmark and Oppland are the only Norwegian counties with no coastline. Hedmark hosted some events of the 1994 Winter Olympic Games. Hamar, Kongsvinger and Tynset are cities in the county. Hedmark is one of the less urbanized areas in Norway; the population is concentrated in the rich agricultural district adjoining Mjøsa to the southeast. The county's extensive forests supply much of Norway's timber; the Hedmark municipality of Engerdal has the distinction of marking the current southernmost border in Norway of Sápmi, the traditional region of the Sami people.
The county is divided into three traditional districts. These are Østerdalen and Solør. Hedmark was a part of the large Akershus amt, but in 1757 Oplandenes amt was separated from it; some years in 1781, this was divided into Kristians amt and Hedemarkens amt. Until 1919, the county was called Hedemarkens amt; the Old Norse form of the name was Heiðmǫrk. The first element is heiðnir, the name of an old Germanic tribe and is related to the word heið, which means moorland; the last element is mǫrk'woodland, march'. The coat of arms is from modern times, it shows three barkespader. Every four years the inhabitants of Hedmark elect 33 representatives to Hedmark Fylkesting, the Hedmark County Assembly. After the elections of September 2007 the majority of the seats of the assembly were held by a three-party coalition consisting of the Labour Party, the Centre Party and the Socialist Left Party. Eight parties are represented in the assembly, the remaining 5 being the Progress Party, the Conservative Party, the Liberal Party, the Christian Democratic Party and the Pensioners Party.
The assembly is headed by the county mayor. As of the 2007 elections the county mayor is Arnfinn Nergård, he represents the Centre Party. In 2003 a parliamentary system was established, which means that the county assembly elects a political administration or council to hold executive power; this county council reflects the majority of the county assembly and includes the three parties holding the majority of the assembly seats, i.e. the Labour Party, the Center Party and the Socialist Left Party. The council is led by a member of the Labour Party. Official homepage Media related to Hedmark at Wikimedia Commons Hedmark travel guide from Wikivoyage
Gutulia National Park
Gutulia National Park is smallest national park in Norway. The landscape consists of lakes and virginal forests, dominated by spruce and birch; because of the climate, growth is slow, many of the spruce trees are hundreds of years old. There is only one marked path through the park. Gutulia lies close to Femundsmarka National Park and protected areas on the Swedish side of the border; the first element is the rivername Gutua, the last element is the finite form of li f'hillside'. The name of the river is derived from gate f'road'. Map of Gutulia National Park
Agriculture is the science and art of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that enabled people to live in cities; the history of agriculture began thousands of years ago. After gathering wild grains beginning at least 105,000 years ago, nascent farmers began to plant them around 11,500 years ago. Pigs and cattle were domesticated over 10,000 years ago. Plants were independently cultivated in at least 11 regions of the world. Industrial agriculture based on large-scale monoculture in the twentieth century came to dominate agricultural output, though about 2 billion people still depended on subsistence agriculture into the twenty-first. Modern agronomy, plant breeding, agrochemicals such as pesticides and fertilizers, technological developments have increased yields, while causing widespread ecological and environmental damage. Selective breeding and modern practices in animal husbandry have increased the output of meat, but have raised concerns about animal welfare and environmental damage.
Environmental issues include contributions to global warming, depletion of aquifers, antibiotic resistance, growth hormones in industrial meat production. Genetically modified organisms are used, although some are banned in certain countries; the major agricultural products can be broadly grouped into foods, fibers and raw materials. Food classes include cereals, fruits, meat, milk and eggs. Over one-third of the world's workers are employed in agriculture, second only to the service sector, although the number of agricultural workers in developed countries has decreased over the centuries; the word agriculture is a late Middle English adaptation of Latin agricultūra, from ager, "field", which in its turn came from Greek αγρός, cultūra, "cultivation" or "growing". While agriculture refers to human activities, certain species of ant and ambrosia beetle cultivate crops. Agriculture is defined with varying scopes, in its broadest sense using natural resources to "produce commodities which maintain life, including food, forest products, horticultural crops, their related services".
Thus defined, it includes arable farming, animal husbandry and forestry, but horticulture and forestry are in practice excluded. The development of agriculture enabled the human population to grow many times larger than could be sustained by hunting and gathering. Agriculture began independently in different parts of the globe, included a diverse range of taxa, in at least 11 separate centres of origin. Wild grains were eaten from at least 105,000 years ago. From around 11,500 years ago, the eight Neolithic founder crops and einkorn wheat, hulled barley, lentils, bitter vetch, chick peas and flax were cultivated in the Levant. Rice was domesticated in China between 11,500 and 6,200 BC with the earliest known cultivation from 5,700 BC, followed by mung and azuki beans. Sheep were domesticated in Mesopotamia between 11,000 years ago. Cattle were domesticated from the wild aurochs in the areas of modern Turkey and Pakistan some 10,500 years ago. Pig production emerged in Eurasia, including Europe, East Asia and Southwest Asia, where wild boar were first domesticated about 10,500 years ago.
In the Andes of South America, the potato was domesticated between 10,000 and 7,000 years ago, along with beans, llamas and guinea pigs. Sugarcane and some root vegetables were domesticated in New Guinea around 9,000 years ago. Sorghum was domesticated in the Sahel region of Africa by 7,000 years ago. Cotton was domesticated in Peru by 5,600 years ago, was independently domesticated in Eurasia. In Mesoamerica, wild teosinte was bred into maize by 6,000 years ago. Scholars have offered multiple hypotheses to explain the historical origins of agriculture. Studies of the transition from hunter-gatherer to agricultural societies indicate an initial period of intensification and increasing sedentism. Wild stands, harvested started to be planted, came to be domesticated. In Eurasia, the Sumerians started to live in villages from about 8,000 BC, relying on the Tigris and Euphrates rivers and a canal system for irrigation. Ploughs appear in pictographs around 3,000 BC. Farmers grew wheat, vegetables such as lentils and onions, fruits including dates and figs.
Ancient Egyptian agriculture relied on its seasonal flooding. Farming started in the predynastic period at the end of the Paleolithic, after 10,000 BC. Staple food crops were grains such as wheat and barley, alongside industrial crops such as flax and papyrus. In India, wheat and jujube were domesticated by 9,000 BC, soon followed by sheep and goats. Cattle and goats were domesticated in Mehrgarh culture by 8,000–6,000 BC. Cotton was cultivated by the 5th-4th millennium BC. Archeological evidence indicates an animal-drawn plough from 2,500 BC in the Indus Valley Civilisation. In China, from the 5th century BC there was a nationwide granary system and widespread silk farming. Water-powered grain mills were in use followed by irrigation. By the late 2nd century, heavy ploughs had been developed with iron mouldboards; these spread westwards across Eurasia. Asian rice was domesticated 8,200–13,500 years ago – depending on the molecular clock estimate, used – on the Pearl River in southern China with a single genetic origin from the wild rice Oryza rufipogon