Charles Martin Hall (December 6, 1863 – December 27, 1914) was an American
inventor, businessman, and chemist. He is best known for his invention in 1886 of an inexpensive method for producing
aluminum
Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...
, which became the first metal to attain widespread use since the prehistoric discovery of iron. He was one of the founders of
Alcoa.
[ Alfred E. Hunt, together with Charles Hall and a group of five other individuals – his partner at the Pittsburgh Testing Laboratory, George Hubbard Clapp; his chief chemist, W. S. Sample; Howard Lash, head of the Carbon Steel Company; Millard Hunsiker, sales manager for the Carbon Steel Company; and Robert Scott, a mill superintendent for the ]Carnegie Steel Company
Carnegie Steel Company was a steel-producing company primarily created by Andrew Carnegie and several close associates to manage businesses at steel mills in the Pittsburgh, Pennsylvania area in the late 19th century. The company was form ...
– raised $20,000 to launch the Pittsburgh Reduction Company, which was later renamed Aluminum Company of America and shortened to Alcoa.
Biography
Early years
Charles Martin Hall was born to Herman Bassett Hall and Sophronia H. Brooks on December 6, 1863, in Thompson, Ohio
Thompson is an unincorporated community in Thompson Township, Geauga County, in the U.S. state of Ohio
Ohio () is a state in the Midwestern region of the United States. Of the fifty U.S. states, it is the 34th-largest by area, and with a po ...
. Charles's father, Herman, graduated from Oberlin College in 1847, and studied for three years at the Oberlin Theological Seminary, where he met his future wife, Sophronia Brooks. They married in 1849, and the next ten years were spent in missionary work in Jamaica
Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of His ...
, where the first five of their eight children were born. They returned to Ohio in 1860, after the outbreak of the Civil War forced the closing of foreign missions. Charles Hall had two brothers and five sisters; one brother died in infancy. One of his sisters was chemist Julia Brainerd Hall (1859–1925), who helped him in his research.
Hall began his education at home, and was taught to read at an early age by his mother.[ At the age of six, he was using his father's 1840s college chemistry book as a reader.] At age 8, he entered public school, and progressed rapidly.
Hall's family moved to Oberlin, Ohio
Oberlin is a city in Lorain County, Ohio, United States, 31 miles southwest of Cleveland. Oberlin is the home of Oberlin College, a liberal arts college and music conservatory with approximately 3,000 students.
The town is the birthplace of th ...
, in 1873. He spent three years at Oberlin High School, and a year at Oberlin Academy
Oberlin Academy Preparatory School, originally Oberlin Institute and then Preparatory Department of Oberlin College, was a private preparatory school in Oberlin, Ohio which operated from 1833 until 1916. It opened as Oberlin Institute which beca ...
in preparation for college.[ During this time, he demonstrated his aptitude for chemistry and invention, carrying out experiments in the kitchen and the woodshed attached to his house. In 1880, at the age of 16, he enrolled at Oberlin College.]
In his second term, Hall attended, with considerable interest, Oberlin Professor Frank Fanning Jewett's lecture on aluminum; it was here that Jewett displayed the sample of aluminum he had obtained from Friedrich Wöhler at Göttingen
Göttingen (, , ; nds, Chöttingen) is a university city in Lower Saxony, central Germany, the capital of the eponymous district. The River Leine runs through it. At the end of 2019, the population was 118,911.
General information
The ori ...
, and remarked, "if anyone should invent a process by which aluminum could be made on a commercial scale, not only would he be a benefactor to the world, but would also be able to lay up for himself a great fortune".
Discovery
Hall's initial experiments in finding an aluminum reduction process were in 1881. He attempted, unsuccessfully, to produce aluminum from clay by smelting with carbon in contact with charcoal and potassium chlorate. He next attempted to improve the electrolytic methods previously established by investigating cheaper methods to produce aluminum chloride
Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula . It forms hexahydrate with the formula , containing six water molecules of hydration. Both are colourless crystals, but samples are often contam ...
, again unsuccessfully. In his senior year, he attempted to electrolyze aluminum fluoride
Aluminium fluoride refers to inorganic compounds with the formula AlF3·''x''H2O. They are all colorless solids. Anhydrous AlF3 is used in the production of aluminium metal. Several occur as minerals.
Occurrence and production
Aside from anhydr ...
in water, but was unable to produce aluminum at the cathode.
In 1884, after setting up a homemade coal-fired furnace and bellows in a shed behind the family home, Hall again tried to find a catalyst that would allow him to reduce aluminum with carbon at high temperatures: "I tried mixtures of alumina and carbon with barium salts, with cryolite, and with carbonate of sodium, hoping to get a double reaction by which the final result would be aluminum. I remember buying some metallic sodium and trying to reduce cryolite, but obtained very poor results. I made some aluminum sulphide but found it very unpromising as a source of aluminum then as it has been ever since".
Hall had to fabricate most of his apparatus and prepare his chemicals, and was assisted by his older sister Julia Brainerd Hall. The basic invention, which he discovered on February 23, 1886, involves passing an electric current through a bath of alumina dissolved in cryolite
Cryolite ( Na3 Al F6, sodium hexafluoroaluminate) is an uncommon mineral identified with the once-large deposit at Ivittuut on the west coast of Greenland, mined commercially until 1987.
History
Cryolite was first described in 1798 by Danish vete ...
, which results in a puddle of aluminum forming in the bottom of the retort. On July 9, 1886, Hall filed for his first patent. This process was also discovered at nearly the same time by the Frenchman Paul Héroult
Paul (Louis-Toussaint) Héroult (10 April 1863 – 9 May 1914) was a French scientist. He was the inventor of the aluminium electrolysis and developed the first successful commercial electric arc furnace. He lived in Thury-Harcourt, Normandy. ...
, and it has come to be known as the Hall–Héroult process
The Hall–Héroult process is the major industrial process for smelting aluminium. It involves dissolving aluminium oxide (alumina) (obtained most often from bauxite, aluminium's chief ore, through the Bayer process) in molten cryolite, and el ...
.
After failing to find financial backing at home, Hall went to Pittsburgh
Pittsburgh ( ) is a city in the Commonwealth of Pennsylvania, United States, and the county seat of Allegheny County. It is the most populous city in both Allegheny County and Western Pennsylvania, the second-most populous city in Pennsylva ...
, where he made contact with noted metallurgist Alfred E. Hunt. They formed the Reduction Company of Pittsburgh, which opened the first large-scale aluminum production plants. The Reduction Company later became the Aluminum Company of America, then Alcoa. Hall was a major stockholder, and became wealthy.[
The Hall–Héroult process eventually resulted in reducing the price of aluminum by a factor of 200, making it affordable for many practical uses. By 1900, annual production reached about . Today, more aluminum is produced than all other non-ferrous metals combined.
Hall is sometimes suggested to be the originator of the American spelling of "aluminum", but that spelling was used briefly by ]Humphry Davy
Sir Humphry Davy, 1st Baronet, (17 December 177829 May 1829) was a British chemist and inventor who invented the Davy lamp and a very early form of arc lamp. He is also remembered for isolating, by using electricity, several elements for t ...
in the early 1800s and was the spelling in Noah Webster
Noah ''Nukh''; am, ኖህ, ''Noḥ''; ar, نُوح '; grc, Νῶε ''Nôe'' () is the tenth and last of the pre-Flood patriarchs in the traditions of Abrahamic religions. His story appears in the Hebrew Bible ( Book of Genesis, chapters 5 ...
's Dictionary of 1828. "Aluminium" was used widely in the United States until 1895 or 1900, and "aluminum" was not officially adopted by the American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all ...
until 1925. Hall's early patents use the spelling "aluminium". In the United Kingdom and other countries using British spelling
Despite the various English dialects spoken from country to country and within different regions of the same country, there are only slight regional variations in English orthography, the two most notable variations being British and American ...
, only the spelling "aluminium" is now used. The spelling in virtually all other languages is analogous to the "-ium" ending.[
]
Later years and death
Hall continued his research and development for the rest of his life and was granted 22 US patents, most on aluminum production. He served on the Oberlin College Board of Trustees. He was vice-president of Alcoa until his death.
Hall died, unmarried and childless, on December 27, 1914, twenty-one days after he had reached the age of 51, in Daytona, Florida. He was buried in Westwood Cemetery in Oberlin.[ He died the same year as Héroult, and they both were born the same year.]
In his last will and testament, Hall left the vast majority of his fortune to charity. His generosity contributed to the establishment of the Harvard-Yenching Institute, a leading foundation dedicated to advancing higher education in Asia in the humanities and social sciences.
Awards and honors
Hall won the Perkin Medal
The Perkin Medal is an award given annually by the Society of Chemical Industry (American Section) to a scientist residing in America for an "innovation in applied chemistry resulting in outstanding commercial development." It is considered the ...
, the highest award that the American section of the Society of Chemical Industry
The Society of Chemical Industry (SCI) is a learned society set up in 1881 "to further the application of chemistry and related sciences for the public benefit".
Offices
The society's headquarters is in Belgrave Square, London. There are semi-in ...
bestows, in 1911. In 1997, the production of aluminum metal by electrochemistry discovered by Hall was designated as a National Historic Chemical Landmark
The National Historic Chemical Landmarks program was launched by the American Chemical Society in 1992 to recognize significant achievements in the history of chemistry and related professions. The program celebrates the The central science, cent ...
by the American Chemical Society
The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all ...
.
Hall eventually became one of Oberlin College's most prominent benefactors, and an aluminum statue of him exists on the campus. Because of its light weight, Hall's statue was once known for its frequent changes of location, often due to student pranks. Today the statue is glued to a large granite block and sits more permanently on the second floor of Oberlin's science center, where students continue to decorate Hall with appropriate trappings on holidays and other occasions.
The Jewett home is preserved in Oberlin as the Oberlin Heritage Center
The Oberlin Heritage Center is a non-profit 501(c)(3) organization, governed by an 18-member Board of Trustees. The organization is funded by memberships, annual fund contributions, investments, grants, fund-raising projects and planned gifts. O ...
. The center features an exhibit called ''Aluminum: The Oberlin Connection'', which includes a re-creation of Hall's 1886 woodshed experiment. The Hall House is also preserved in Oberlin, although the woodshed was demolished long ago.
Patents
* US Patent 400,664
''Process of reducing aluminium from its fluoride salts by electrolysis'' — C. M. Hall, applied 1886, granted 1889. TIFF Image of page from USPTO
See also
* History of aluminium
Aluminium (or aluminum) metal is very rare in native form, and the process to refine it from ores is complex, so for most of human history it was unknown. However, the compound alum has been known since the 5th century BCE and was used extensive ...
References
External links
* Finding Ai
RG 30/182 – Charles Martin Hall (1863–1914)
Oberlin College Archives
{{DEFAULTSORT:Hall, Charles Martin
1863 births
1914 deaths
People from Geauga County, Ohio
Oberlin College alumni
19th-century American inventors
20th-century American inventors
American chemists
Alcoa people