This
invisible
gas,
this
breath
of
air,
through
the
magic
of
chemical
combination,
forms
nearly
half
the
substance
of
the
solid
rocks.
"The Breath of Life", John Burroughs
I
will
not
answer
for
the
form,
but
the
substance
I
am
sure
of.
"Louise de la Valliere", Alexandre Dumas, Pere