of terrestrial vapors, which
circumstance was doubtless owing to the extreme density of the air.

I use the word "cavern" in order to give an idea of the place. I cannot
describe its awful grandeur; human language fails to convey an idea of
its savage sublimity. Whether this singular vacuum had or had not been
caused by the sudden cooling of the earth when in a state of fusion, I
could not say. I had read of most wonderful and gigantic caverns--but,
none in any way like this.

The great grotto of Guachara, in Colombia, visited by the learned
Humboldt; the vast and partially explored Mammoth Cave in Kentucky--what
were these holes in the earth to that in which I stood in speechless
admiration! with its vapory clouds, its electric light, and the mighty
ocean slumbering in its bosom! Imagination, not description, can alone
give an idea of the splendor and vastness of the cave.

I gazed at these marvels in profound silence. Words were utterly wanting
to indicate the sensations of wonder I experienced. I seemed, as I stood
upon that mysterious shore, as if I were some wandering inhabitant of a
distant planet, present for the first time at the spectacle of some
terrestrial phenomena belonging to another existence. To give body and
existence to such new sensations would have required the coinage of new
words--and here my feeble brain found itself wholly at fault. I looked
on, I thought, I reflected, I admired, in a state of stupefaction not
altogether unmingled with fear!

The unexpected spectacle restored some color to my pallid cheeks. I
seemed to be actually getting better under the influence of this
novelty. Moreover, the vivacity of the dense atmosphere reanimated my
body by inflating my lungs with unaccustomed oxygen.

It will be readily conceived that after an imprisonment of forty-seven
days, in a dark and miserable tunnel it was with infinite delight that I
breathed this saline air. It was like the genial, reviving influence of
the salt sea waves.

My uncle had already got over the first surprise.

With the Latin poet Horace his idea was that--

Not to admire is all the art I know,

To make man happy and to keep him so.

"Well," he said, after giving me time thoroughly to appreciate the
marvels of this underground sea, "do you feel strong enough to walk up
and down?"

"Certainly," was my ready answer, "nothing would give me greater
pleasure."

"Well then, my boy," he said, "lean on my arm, a