he development of the electric furnace America played a pioneer
part. Provost Smith of the University of Pennsylvania, who is the best
authority on the history of chemistry in America, claims for Robert
Hare, a Philadelphia chemist born in 1781, the honor of constructing the
first electrical furnace. With this crude apparatus and with no greater
electromotive force than could be attained from a voltaic pile, he
converted charcoal into graphite, volatilized phosphorus from its
compounds, isolated metallic calcium and synthesized calcium carbide. It
is to Hare also that we owe the invention in 1801 of the oxy-hydrogen
blowpipe, which nowadays is used with acetylene as well as hydrogen.
With this instrument he was able to fuse strontia and volatilize
platinum.

But the electrical furnace could not be used on a commercial scale until
the dynamo replaced the battery as a source of electricity. The
industrial development of the electrical furnace centered about the
search for a cheap method of preparing aluminum. This is the metallic
base of clay and therefore is common enough. But clay, as we know from
its use in making porcelain, is very infusible and difficult to
decompose. Sixty years ago aluminum was priced at $140 a pound, but one
would have had difficulty in buying such a large quantity as a pound at
any price. At international expositions a small bar of it might be seen
in a case labeled "silver from clay." Mechanics were anxious to get the
new metal, for it was light and untarnishable, but the metallurgists
could not furnish it to them at a low enough price. In order to extract
it from clay a more active metal, sodium, was essential. But sodium also
was rare and expensive. In those days a professor of chemistry used to
keep a little stick of it in a bottle under kerosene and once a year he
whittled off a piece the size of a pea and threw it into water to show
the class how it sizzled and gave off hydrogen. The way to get cheaper
aluminum was, it seemed, to get cheaper sodium and Hamilton Young
Castner set himself at this problem. He was a Brooklyn boy, a student of
Chandler's at Columbia. You can see the bronze tablet in his honor at
the entrance of Havemeyer Hall. In 1886 he produced metallic sodium by
mixing caustic soda with iron and charcoal in an iron pot and heating in
a gas furnace. Before this experiment sodium sold at $2 a pound; after
it sodium sold at twenty cents a pound.

But although Castner had succee