ded in his experiment he was defeated in
his object. For while he was perfecting the sodium process for making
aluminum the electrolytic process for getting aluminum directly was
discovered in Oberlin. So the $250,000 plant of the "Aluminium Company
Ltd." that Castner had got erected at Birmingham, England, did not make
aluminum at all, but produced sodium for other purposes instead. Castner
then turned his attention to the electrolytic method of producing sodium
by the use of the power of Niagara Falls, electric power. Here in 1894
he succeeded in separating common salt into its component elements,
chlorine and sodium, by passing the electric current through brine and
collecting the sodium in the mercury floor of the cell. The sodium by
the action of water goes into caustic soda. Nowadays sodium and chlorine
and their components are made in enormous quantities by the
decomposition of salt. The United States Government in 1918 procured
nearly 4,000,000 pounds of chlorine for gas warfare.

The discovery of the electrical process of making aluminum that
displaced the sodium method was due to Charles M. Hall. He was the son
of a Congregational minister and as a boy took a fancy to chemistry
through happening upon an old text-book of that science in his father's
library. He never knew who the author was, for the cover and title page
had been torn off. The obstacle in the way of the electrolytic
production of aluminum was, as I have said, because its compounds were
so hard to melt that the current could not pass through. In 1886, when
Hall was twenty-two, he solved the problem in the laboratory of Oberlin
College with no other apparatus than a small crucible, a gasoline burner
to heat it with and a galvanic battery to supply the electricity. He
found that a Greenland mineral, known as cryolite (a double fluoride of
sodium and aluminum), was readily fused and would dissolve alumina
(aluminum oxide). When an electric current was passed through the melted
mass the metal aluminum would collect at one of the poles.

In working out the process and defending his claims Hall used up all his
own money, his brother's and his uncle's, but he won out in the end and
Judge Taft held that his patent had priority over the French claim of
Herault. On his death, a few years ago, Hall left his large fortune to
his Alma Mater, Oberlin.

Two other young men from Ohio, Alfred and Eugene Cowles, with whom Hall
was for a time associated, wore the