Original sentence: Detroit became an early steel producing city in North America due to easy access to Great Lakes shipping and iron ore from northern Michigan, Wisconsin and Minnesota.The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron.The capacity of a converter was from 8 to 30 tons of molten iron with a usual charge being around 15 tons.The first Bessemer steel mill in the United States was established in 1855 in Wyandotte, Michigan, on the Detroit River, about 14 miles south of Detroit.The key principle is removal of impurities from the iron by oxidation with air being blown through the molten iron.The oxidation also raises the temperature of the iron mass and keeps it molten.The process had also been used outside of Europe for hundreds of years, but not on an industrial scale.The process was independently discovered in 1851 by William Kelly.These were major factors in development of Detroit as a renowned center of automobile manufacture
Edited sentence: Americans once learned that the process was independently discovered by William Kelly, but there is little evidence that Kelly came up with his ideas independently.And the Bessemer process shot a fiery blast of polluting gases into the environment.Modern metallurgical analysis does not indicate steel was ever made in it.Steel had also been used outside of Europe for hundreds of years, but not on an industrial scale.Steel manufacturing instead gravitated mostly to established iron producing centers, including Pittsburgh.Strangely enough, Detroit did not become an early steel producing city despite its easy access to Great Lakes shipping and iron ore from northern Michigan, Wisconsin and Minnesota.The Bessemer process was the first industrial process for the mass production of steel from molten pig iron.The capacity of a converter was from 5 to 30 tons of molten iron with a usual charge being around 15 tons.The key principle is removal of excess carbon from the iron by oxidation with air being blown through the molten iron.The oxidation also raises the temperature of the liquid iron mass and keeps it molten.The pioneering steel mill in the United States made its first batch of Bessemer steel in September 1864 in Wyandotte, Michigan, on the Detroit River, about 14 miles south of Detroit.The so-called Kelly converter, displayed at the Smithsonian for years, was constructed years after the fact