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TF閱讀真題第359篇Cotton Ginning and Interchangeable Parts:The Legacy o

2023-04-09 15:31 作者:bili_85023506665  | 我要投稿

Cotton Ginning and Interchangeable Parts:The Legacy of Eli Whitney

Cotton is a soft fiber that grows around the seeds of the cotton plant.It was first cultivated in the Indus Valley about 6,000 years ago and then spread to Egypt,Persia,China,and the Mediterranean.For thousands of years,the cultivation of cotton was very labor-intensive. Many steps were involved in preparing cotton to be used in a garment,and many machines were invented to make cotton more valuable as a general-purpose textile material.

The process of separating cotton fibers from seeds is called ginning,which is depicted as far back as the fifth century in paintings in the Ajanta Caves in India.Egyptian cotton has the longest fibers and is used to make premium fabrics.In the American South,the high quality long-staple cotton can be grown only in a narrow band along the Carolina and Georgia coast and is called Sea Island cotton.The interior areas of the American South can only grow Upland short- staple cotton.The shorter-length fibers mean reduced yarn and cloth quality,and they have “fuzzy”seeds because the fibers are tightly attached to the entire seed surface.This strong attachment of fibers to seeds makes it difficult to remove the fibers without damage,which made the process expensive as it was time-consuming and labor- intensive.These time-consuming tasks were done by slaves in the American southern states during the 1800s.

The modern cotton gin was invented by the American Eli Whitney (1765-1825),who graduated from Yale University in 1789 and is known for two great inventions:the cotton gin,which transformed the southern economy,and interchangeable parts in machinery,which led to the mass-production method of manufacturing.When he graduated,he was short of funds and went to Georgia to seek his fortune in plantations.He was introduced to the problem of finding a better way to gin the Upland short-fiber cotton,which led him to invent the cotton gin in 1794.Whitney’s cotton gin made the mechanical separation of fiber from seeds much more efficient.His machine had spiked sawteeth mounted on a revolving cylinder in a box,which was turned by a crank.The teeth pulled the cotton fiber through small slotted openings that were too small for the seeds to pass;thus,the lint was separated from the seeds.Then a rotating brush removed the fibrous lint from the teeth,and the seeds fell into a hopper.Whitney’s machine could separate up to 50 pounds of cleaned cotton daily, making cotton production profitable for the southern states.

Unfortunately for Whitney,his cotton gin was extremely simple and easy to copy,so he failed to profit from his invention.Soon after, imitations of his machine appeared,and his 1794 patent for the cotton gin could not be upheld in court until 1807.Instead,he decided to make money by going into the ginning business,and manufactured and installed cotton gins through Georgia and the southern states. However,his ginning plants were resented by the planters,who thought that he charged too much,and hence they found ways to circumvent his patent.

In later years,Eli Whitney cultivated social and political connections through his status as a Yale alumnus and through his marriage.Although he had never made a gun in his life,through those connections he won a contract from the War Department in 1798 to make and deliver 10,000 muskets (firearms used by soldiers before the invention of the rifle)for the army in 1800.Treasury Secretary Wolcott sent him a “foreign pamphlet on arms manufacturing techniques,and Whitney began to talk about interchangeable parts.This concept was a departure from the usual method of having an individual master machinist make each part of the musket and fit them together,which is slow and painstaking. Whitney’s method was to have many less skilled machinists specialize in making only one part per person to highly specified dimensions,so that the parts would be interchangeable and could then be assembled.This is the heart of the mass-production method later made more famous by Henry Ford in the manufacture of the Model T automobile.Whitney ultimately delivered on the army contract in 1809,and he spent the rest of his life promoting interchangeability.?

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?Cotton is a soft fiber that grows around the seeds of the cotton plant.It was first cultivated in the Indus Valley about 6,000 years ago and then spread to Egypt,Persia,China,and the Mediterranean.For thousands of years,the cultivation of cotton was very labor-intensive. Many steps were involved in preparing cotton to be used in a?garment,and many machines were invented to make cotton more valuable as a general-purpose textile material.?


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