excess of liquid; the second supposes a body capable of dissolving carbon, and allowing it to crystallize by evaporation.
Another
theory was advanced by Sir David Brewster concerning the origin of the
diamond. He supposed that this beautiful gem is of organic origin, and
he was led to this opinion by examining the diamond microscopically,
when he discovered certain striations and dispositions that resembled
the fibres of organic substances, and particularly of certain species of wood.
These
are but suppositions, however, and we really know nothing for certain
regarding the origin of the diamond. The most we can say is that it is
very improbable the diamond was produced under the action of a high
temperature.
The
knowledge of the chemical composition of the diamond is so recent that
all the experiments made with the least chance of success to reproduce
it have occurred within the last half century.
In
1828 two interesting experiments were made nearly at the same time by
Cagniard de Latour and Gannal; De Latour presented his results to the
Academy of Sciences, Oct. 10, 1828; and those of Gannal were presented
the 23d of November the same year.
Cagniard de Latour sent to the Academy of Sciences ten tubes containing a number of light-
