|
FIRE IN THE EARTH
matter.
It is in your body: one-eighth of the human body is carbon. Wood is
half carbon. It exists too in the food we eat, the clothes we wear, and
even the air we breathe. ;The things that make other things go—coal,
fuel oil, gasoline—contain carbon. Perhaps Nature had in mind turning
all carbon into diamonds, but the carbon usually escaped the trap of
molten lava and heat and pressure.
So
a piece of charcoal, for instance, didn't become a diamond because it
escaped Nature's prearranged processes. Yet the charcoal, as Faraday
said, is just the same as the diamonds you wear, only "differently
coalesced." Practically, the big difference is in the softness of
charcoal, the hardness of the diamond. The diamond is the hardest
substance in existence—indeed, it is by far the hardest. Consider
corundum. It is the hardest natural substance, next to the diamond.
Sapphires and rubies are corundum. But the diamond is about
eighty-five times as hard as corundum and, in fact, is used to shape
the hard surface of emery, of carborundum and of tungsten carbide. If
you go into a stone yard you will see diamond-impregnated saws cutting through massive
blocks of stone as though they were as soft as cheese. A diamond tool
set on a lathe can wear away two big emery wheels a foot and a half in
diameter and an inch thick before the diamond itself shows any wear and
tear.
Benvenuto
Cellini, himself a master-goldsmith jeweler of his time (since we are
determined to ignore footnotes in this book it might as well be said he
flourished from 1500 to 1571), tells a remarkable and typically
imaginative story about the use of diamonds as applied to him. It
demonstrates their hardness as well as the perfidy of mankind. It
seems that while imprisoned Cellini was in danger of being put to death
by foul means. A Mr. Durante of Brescia engaged a soldier to administer
to Cellini some deadly
(4)
|
||
|
|
||