175th Anniversary of Oberlin College and the City of Oberlin: 1833 - 2008

Patience, Patent Pay off for Young Chemist

Charles Martin Hall is widely known as the first person to discover an inexpensive way to extract aluminum metal from its ore. However, in an era when chemistry was rapidly developing, a French scientist emerged with his own discovery and patent application at virtually the same time--setting up a legal battle that ended in Hall’s favor.

Hall grew up in Oberlin and enrolled at Oberlin College in 1880. He was curious about science and aspired to become a successful inventor and entrepreneur. Under the guidance of Oberlin chemistry Professor Frank Jewett, Hall began experimenting with a practical process for extracting aluminum from its ore with an electric current. After graduating from Oberlin in 1885, Hall applied for a patent and began producing aluminum metal on an industrial scale.

Before 1886, aluminum was a semiprecious metal discovered in 1825. Yet the only way to prepare it was by a sodium-reduction method that was so expensive, many considered it as valuable as a large piece of silver.

After many unsuccessful experiments with chemical methods, Hall and Jewett turned to electric current. Hall set up his laboratory outside his family’s home in an attached woodshed in Oberlin. On February 23, 1886, less than eight months after graduating, his experiments paid off. Hall produced aluminum metal by passing an electric current through a solution of aluminum oxide in molten cryolite. On July 9, he filed for a patent for the Process of Reducing Aluminum by Electrolysis.

Meanwhile, French scientist Paul L.T. Héroult received a French patent on April 2, 1886, for a comparable process. He also applied for a U.S. patent in May 1886. Independently, the two inventors made the same discovery at nearly the same time. Under U.S. patent law, patent rights required proof of the date of discovery. Through evidence and testimony from his family and Jewett, Hall established priority of his discovery and received patent rights in the United States.

After being awarded his patent, Hall continued to develop his process, later  selling the rights of his invention to the Aluminum Company of America (ALCOA), a Cleveland manufacturing company that brought the inventor’s process to a commercial scale.

However, Hall’s legal battles over the ownership of his process were not over. In 1893, Judge William Howard Taft ruled in favor of Hall and the originality of his invention.

Hall was a generous benefactor of Oberlin College. In his lifetime, he made several direct gifts, and his estate left more than $10 million for the College endowment, as well as money for an auditorium.

Read more about Hall and the history of ALCOA.

Sources: Electronic Oberlin Group, Oberlin College Archives