we entered the somber gallery!

Just as we were about to engulf ourselves in this dismal passage, I
lifted up my head, and through the tubelike shaft saw that Iceland sky I
was never to see again!

Was it the last I should ever see of any sky?

The stream of lava flowing from the bowels of the earth in 1219 had
forced itself a passage through the tunnel. It lined the whole of the
inside with its thick and brilliant coating. The electric light added
very greatly to the brilliancy of the effect.

The great difficulty of our journey now began. How were we to prevent
ourselves from slipping down the steeply inclined plane? Happily some
cracks, abrasures of the soil, and other irregularities, served the
place of steps; and we descended slowly; allowing our heavy luggage to
slip on before, at the end of a long cord.

But that which served as steps under our feet became in other places
stalactites. The lava, very porous in certain places, took the form of
little round blisters. Crystals of opaque quartz, adorned with limpid
drops of natural glass suspended to the roof like lusters, seemed to
take fire as we passed beneath them. One would have fancied that the
genii of romance were illuminating their underground palaces to receive
the sons of men.

"Magnificent, glorious!" I cried in a moment of involuntary enthusiasm,
"What a spectacle, Uncle! Do you not admire these variegated shades of
lava, which run through a whole series of colors, from reddish brown to
pale yellow--by the most insensible degrees? And these crystals, they
appear like luminous globes."

"You are beginning to see the charms of travel, Master Harry," cried my
uncle. "Wait a bit, until we advance farther. What we have as yet
discovered is nothing--onwards, my boy, onwards!"

It would have been a far more correct and appropriate expression, had he
said, "let us slide," for we were going down an inclined plane with
perfect ease. The compass indicated that we were moving in a
southeasterly direction. The flow of lava had never turned to the right
or the left. It had the inflexibility of a straight line.

Nevertheless, to my surprise, we found no perceptible increase in heat.
This proved the theories of Humphry Davy to be founded on truth, and
more than once I found myself examining the thermometer in silent
astonishment.

Two hours after our departure it only marked fifty-four degrees
Fahrenheit. I had every reason to believe from this that our desc