BORT CARBONS, ETC. 327
pressure,
would dissolve carbon, and that diamond might crystallize out of the
solution. Experiments in this direction, however, failed to dissolve
the carbon.
Liebig
thought that pure carbon in the crystallized form was the final result
of the gradual decomposition of a fluid hydro-carbon at a low
temperature. Another scientist claimed that such a separation could
only take place by the action of heat. One thought that the diamond
crystallized out of carbon volatilized by volcanic heat, and yet
another was of the opinion that it was formed from an excess of carbon
during the oxidation of the emanations of a gaseous hydro-carbon.
The
decomposition of various mineral compounds of which carbon was a
constituent, is believed by many to have been the method by which,
during the chemical reactions, diamond was precipitated as a crystal.
Others discredit the solution theory and maintain that it was
accomplished by the interaction of gases.
Professor
Moissan, the most successful experimenter, obtained diamonds by a
combination of heat and pressure simultaneously applied to a solution
containing carbon. Knowing that molten iron was a good solvent for
carbon, he took iron filings and charged them with pure sugar charcoal.
Placing the mass in an electric furnace of his own construction, in
which he was able to concentrate the energy of 100 horse power upon the
crucible, and produce a temperature between 6,ooo° and 7,000° F., he
melted the carbon-charged iron to an ingot. When at this tremendous
heat the iron began to vaporize, he plunged the seething metal into
water or molten lead, solidifying the outer skin of the ingot by the
sudden cooling, about the still liquid interior.
