paragraph_text: Cotton picking was originally done by hand. In many societies, like America, slave and serf labor was utilized to pick the cotton, increasing the plantation owner's profit margins (See Trans - Atlantic Slave Trade). The first practical cotton picker was invented over a period of years beginning in the late 1920s by John Daniel Rust (1892 -- 1954) with the later help of his brother Mack Rust. Other inventors had tried designs with a barbed spindle to twist cotton fibers onto the spindle and then pull the cotton from the boll, but these early designs were impractical because the spindle became clogged with cotton. Rust determined that a smooth, moist spindle could be used to strip the fibers from the boll without trapping them in the machinery. In 1933 John Rust received his first patent, and eventually, he and his brother owned forty - seven patents on cotton picking machinery. However, during the Great Depression it was difficult to obtain financing to develop their inventions.

paragraph_text: During the late medieval period, cotton became known as an imported fiber in northern Europe, without any knowledge of how it was derived, other than that it was a plant. Because Herodotus had written in his Histories, Book III, 106, that in India trees grew in the wild producing wool, it was assumed that the plant was a tree, rather than a shrub. This aspect is retained in the name for cotton in several Germanic languages, such as German Baumwolle, which translates as "tree wool" (Baum means "tree"; Wolle means "wool"). Noting its similarities to wool, people in the region could only imagine that cotton must be produced by plant-borne sheep. John Mandeville, writing in 1350, stated as fact the now-preposterous belief: "There grew there [India] a wonderful tree which bore tiny lambs on the endes of its branches. These branches were so pliable that they bent down to allow the lambs to feed when they are hungrie  [sic]." (See Vegetable Lamb of Tartary.) By the end of the 16th century, cotton was cultivated throughout the warmer regions in Asia and the Americas.

paragraph_text: Beginning as a self-help program in the mid-1960s, the Cotton Research and Promotion Program (CRPP) was organized by U.S. cotton producers in response to cotton's steady decline in market share. At that time, producers voted to set up a per-bale assessment system to fund the program, with built-in safeguards to protect their investments. With the passage of the Cotton Research and Promotion Act of 1966, the program joined forces and began battling synthetic competitors and re-establishing markets for cotton. Today, the success of this program has made cotton the best-selling fiber in the U.S. and one of the best-selling fibers in the world.[citation needed]

paragraph_text: A Cotton Office in New Orleans is an 1873 oil painting by Edgar Degas. In it, Degas depicts his uncle Michel Musson's cotton brokerage business (which several years later went bankrupt in an economic crash, according to Michael McMahon of the "Pittsburgh Post-Gazette" when the firm was swamped by the postwar growth of the much larger Cotton Exchange). In the painting, Musson is seen examining raw cotton for its quality while Degas' brother Rene reads "The Daily Picayune". Another brother, Achille, rests against a window wall at left while others, including Musson's partners, go about their business.

paragraph_text: Worldwide prosperity changed dramatically with the onset of the Great Depression in 1929. The Wall Street Crash of 1929 served to punctuate the end of the previous era, as The Great Depression set in. The Great Depression was a worldwide economic downturn starting in most places in 1929 and ending at different times in the 1930s or early 1940s for different countries. It was the largest and most important economic depression in the 20th century, and is used in the 21st century as an example of how far the world's economy can fall.

paragraph_text: Cotton remains a major export of the southern United States, and a majority of the world's annual cotton crop is of the long - staple American variety.

paragraph_text: Production capacity in Britain and the United States was improved by the invention of the cotton gin by the American Eli Whitney in 1793. Before the development of cotton gins, the cotton fibers had to be pulled from the seeds tediously by hand. By the late 1700s a number of crude ginning machines had been developed. However, to produce a bale of cotton required over 600 hours of human labor, making large-scale production uneconomical in the United States, even with the use of humans as slave labor. The gin that Whitney manufactured (the Holmes design) reduced the hours down to just a dozen or so per bale. Although Whitney patented his own design for a cotton gin, he manufactured a prior design from Henry Odgen Holmes, for which Holmes filed a patent in 1796. Improving technology and increasing control of world markets allowed British traders to develop a commercial chain in which raw cotton fibers were (at first) purchased from colonial plantations, processed into cotton cloth in the mills of Lancashire, and then exported on British ships to captive colonial markets in West Africa, India, and China (via Shanghai and Hong Kong).

paragraph_text: Current estimates for world production are about 25 million tonnes or 110 million bales annually, accounting for 2.5% of the world's arable land. China is the world's largest producer of cotton, but most of this is used domestically. The United States has been the largest exporter for many years. In the United States, cotton is usually measured in bales, which measure approximately 0.48 cubic meters (17 cubic feet) and weigh 226.8 kilograms (500 pounds).

paragraph_text: The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east - to - west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe. Several walls were being built as early as the 7th century BC; these, later joined together and made bigger and stronger, are collectively referred to as the Great Wall. Especially famous is the wall built in 220 -- 206 BC by Qin Shi Huang, the first Emperor of China. Little of that wall remains. The Great Wall has been rebuilt, maintained, and enhanced over various dynasties; the majority of the existing wall is from the Ming Dynasty (1368 -- 1644).

paragraph_text: The Great Wall stretches from Dandong in the east to Lop Lake in the west, along an arc that roughly delineates the southern edge of Inner Mongolia. A comprehensive archaeological survey, using advanced technologies, has concluded that the Ming walls measure 8,850 km (5,500 mi). This is made up of 6,259 km (3,889 mi) sections of actual wall, 359 km (223 mi) of trenches and 2,232 km (1,387 mi) of natural defensive barriers such as hills and rivers. Another archaeological survey found that the entire wall with all of its branches measure out to be 21,196 km (13,171 mi). Today, the Great Wall is generally recognized as one of the most impressive architectural feats in history.

paragraph_text: In addition to concerns over subsidies, the cotton industries of some countries are criticized for employing child labor and damaging workers' health by exposure to pesticides used in production. The Environmental Justice Foundation has campaigned against the prevalent use of forced child and adult labor in cotton production in Uzbekistan, the world's third largest cotton exporter. The international production and trade situation has led to "fair trade" cotton clothing and footwear, joining a rapidly growing market for organic clothing, fair fashion or "ethical fashion". The fair trade system was initiated in 2005 with producers from Cameroon, Mali and Senegal.

paragraph_text: The invention of the cotton gin caused massive growth in the production of cotton in the United States, concentrated mostly in the South. Cotton production expanded from 750,000 bales in 1830 to 2.85 million bales in 1850. As a result, the region became even more dependent on plantations and slavery, with plantation agriculture becoming the largest sector of its economy. While it took a single slave about ten hours to separate a single pound of fiber from the seeds, a team of two or three slaves using a cotton gin could produce around fifty pounds of cotton in just one day. The number of slaves rose in concert with the increase in cotton production, increasing from around 700,000 in 1790 to around 3.2 million in 1850. By 1860, black slave labor from the American South was providing two - thirds of the world's supply of cotton, and up to 80% of the crucial British market. The cotton gin thus ``transformed cotton as a crop and the American South into the globe's first agricultural powerhouse ''.

paragraph_text: GM cotton acreage in India grew at a rapid rate, increasing from 50,000 hectares in 2002 to 10.6 million hectares in 2011. The total cotton area in India was 12.1 million hectares in 2011, so GM cotton was grown on 88% of the cotton area. This made India the country with the largest area of GM cotton in the world. A long-term study on the economic impacts of Bt cotton in India, published in the Journal PNAS in 2012, showed that Bt cotton has increased yields, profits, and living standards of smallholder farmers. The U.S. GM cotton crop was 4.0 million hectares in 2011 the second largest area in the world, the Chinese GM cotton crop was third largest by area with 3.9 million hectares and Pakistan had the fourth largest GM cotton crop area of 2.6 million hectares in 2011. The initial introduction of GM cotton proved to be a success in Australia – the yields were equivalent to the non-transgenic varieties and the crop used much less pesticide to produce (85% reduction). The subsequent introduction of a second variety of GM cotton led to increases in GM cotton production until 95% of the Australian cotton crop was GM in 2009 making Australia the country with the fifth largest GM cotton crop in the world. Other GM cotton growing countries in 2011 were Argentina, Myanmar, Burkina Faso, Brazil, Mexico, Colombia, South Africa and Costa Rica.

paragraph_text: Engineering achievements of the revolution ranged from electrification to developments in materials science. The advancements made a great contribution to the quality of life. In the first revolution, Lewis Paul was the original inventor of roller spinning, the basis of the water frame for spinning cotton in a cotton mill. Matthew Boulton and James Watt's improvements to the steam engine were fundamental to the changes brought by the Industrial Revolution in both the Kingdom of Great Britain and the world.

paragraph_text: The Calico Acts (1700, 1721) banned the import of most cotton textiles into England, followed by the restriction of sale of most cotton textiles. It was a form of economic protectionism, largely in response to India (particularly Bengal), which dominated world cotton textile markets at the time. The Acts were a precursor to the Industrial Revolution, when Britain eventually surpassed India as the world's leading textile manufacturer in the 19th century.

paragraph_text: Though known since antiquity the commercial growing of cotton in Egypt only started in 1820's, following a Frenchman, by the name of M. Jumel, propositioning the then ruler, Mohamed Ali Pasha, that he could earn a substantial income by growing an extra-long staple Maho (Barbadence) cotton, in Lower Egypt, for the French market. Mohamed Ali Pasha accepted the proposition and granted himself the monopoly on the sale and export of cotton in Egypt; and later dictated cotton should be grown in preference to other crops. By the time of the American Civil war annual exports had reached $16 million (120,000 bales), which rose to $56 million by 1864, primarily due to the loss of the Confederate supply on the world market. Exports continued to grow even after the reintroduction of US cotton, produced now by a paid workforce, and Egyptian exports reached 1.2 million bales a year by 1903.

paragraph_text: The advent of the Industrial Revolution in Britain provided a great boost to cotton manufacture, as textiles emerged as Britain's leading export. In 1738, Lewis Paul and John Wyatt, of Birmingham, England, patented the roller spinning machine, as well as the flyer-and-bobbin system for drawing cotton to a more even thickness using two sets of rollers that traveled at different speeds. Later, the invention of the James Hargreaves' spinning jenny in 1764, Richard Arkwright's spinning frame in 1769 and Samuel Crompton's spinning mule in 1775 enabled British spinners to produce cotton yarn at much higher rates. From the late 18th century on, the British city of Manchester acquired the nickname "Cottonopolis" due to the cotton industry's omnipresence within the city, and Manchester's role as the heart of the global cotton trade.

paragraph_text: Historically, in North America, one of the most economically destructive pests in cotton production has been the boll weevil. Due to the US Department of Agriculture's highly successful Boll Weevil Eradication Program (BWEP), this pest has been eliminated from cotton in most of the United States. This program, along with the introduction of genetically engineered Bt cotton (which contains a bacterial gene that codes for a plant-produced protein that is toxic to a number of pests such as cotton bollworm and pink bollworm), has allowed a reduction in the use of synthetic insecticides.

paragraph_text: Texas produces more cotton than any other state in the United States. With eight production regions around Texas, and only four geographic regions, it is the state's leading cash crop. Texas produces approximately 25% of the country's cotton crop on more than 6 million acres, the equivalent of over 9,000 square miles (23,000 km) of cotton fields. Texas Cotton Producers includes nine certified cotton grower organizations; it addresses national and statewide cotton grower issues, such as the national farm bill and environmental legislation.

paragraph_text: The Great Wall of China is a series of fortifications made of stone, brick, tamped earth, wood, and other materials, generally built along an east - to - west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe with an eye to expansion. Several walls were being built as early as the 7th century BC; these, later joined together and made bigger and stronger, are collectively referred to as the Great Wall. Especially famous is the wall built in 220 -- 206 BC by Qin Shi Huang, the first Emperor of China. Little of that wall remains. The Great Wall has been rebuilt, maintained, and enhanced over various dynasties; the majority of the existing wall is from the Ming Dynasty (1368 -- 1644).

Question: Where does the great wall of the country producing the most cotton in the world end?
Answer: Lop Lake in the west