It was at this epoch that the rocks called feldspars, syenites, and porphyries appeared.

But as a natural consequence of this overflow, the depth of the island increased. It can readily be believed what an enormous quantity of elastic fluids were piled up within its centre, when at last it afforded no other openings, after the process of cooling the crust had taken place.

At length a time came when despite the enormous thickness and weight of the upper crust, the mechanical forces of the combustible gases below became so great, that they actually upheaved the weighty back and made for themselves huge and gigantic shafts. Hence the volcanoes which suddenly arose through the upper crust, and next the craters, which burst forth at the summit of these new creations.

It will be seen that the first phenomena in connection with the formation of the island were simply eruptive; to these, however, shortly succeeded the volcanic phenomena.

Through the newly formed openings, escaped the marvelous mass of basaltic stones with which the plain we were now crossing was covered. We were trampling our way over heavy rocks of dark grey color, which, while cooling, had been moulded into six-sided prisms. In the "back distance" we could see a number of flattened cones, which formerly were so many fire-vomiting mouths.

After the basaltic eruption was appeased and set at rest, the volcano, the force of which increased with that of the extinct craters, gave free passage to the fiery overflow of lava, and to the mass of cinders and pumice stone, now scattered over the sides of the mountain, like disheveled hair on the shoulders of a Bacchante.

Here, in a nutshell, I had the whole history of the phenomena from which Iceland arose. All take their rise in the fierce action of interior fires, and to believe that the central mass did not remain in a state of liquid fire, white hot, was simply and purely madness.

This being satisfactorily proved (Q.E.D.), what insensate folly to pretend to penetrate into the interior of the mighty earth!

This mental lecture delivered to myself while proceeding on a journey, did me good. I was quite reassured as to the fate of our enterprise; and therefore went, like a brave soldier mounting a bristling battery, to the assault of old Sneffels.

As we advanced, the road became every moment more difficult. The soil was broken and dangerous. The rocks broke and gave way under our feet, and we had to be scrupulously careful in order to avoid dangerous and constant falls.

Hans advanced as calmly as if he had been walking over Salisbury Plain; sometimes he would disappear behind huge blocks of stone, and we momentarily lost sight of him. There was a little period of anxiety and then there was a shrill whistle, just to tell us where to look for him.

Occasionally he would take it into his head to stop to pick up lumps of rock, and silently pile them up into small heaps, in order that we might not lose our way on our return.

He had no idea of the journey we were about to undertake.

At all events, the precaution was a good one; though how utterly useless and unnecessary--but I must not anticipate.

Three hours of terrible fatigue, walking incessantly, had only brought us to the foot of the great mountain. This will give some notion of what we had still to undergo.

Suddenly, however, Hans cried a halt--that is, he made signs to that effect--and a summary kind of breakfast was laid out on the lava before us. My uncle, who now was simply Professor Hardwigg, was so eager to advance, that he bolted his food like a greedy clown. This halt for refreshment was also a halt for repose. The Professor was therefore compelled to wait the good pleasure of his imperturbable guide, who did not give the signal for departure for a good hour.

The three Icelanders, who were as taciturn as their comrade, did not say a word; but went on eating and drinking very quietly and soberly.

From this, our first real stage, we began to ascend the slopes of the Sneffels volcano. Its magnificent snowy nightcap, as we began to call it, by an optical delusion very common in mountains, appeared to me to be close at hand; and yet how many long weary hours must elapse before we reached its summit. What unheard-of fatigue must we endure!

The stones on the mountain side, held together by no cement of soil, bound together by no roots or creeping herbs, gave way continually under our feet, and went rushing below into the plains, like a series of small avalanches.

In certain places the sides of this stupendous mountain were at an angle so steep that it was impossible to climb upwards, and we were compelled to get round these obstacles as best we might.

Those who understand Alpine climbing will comprehend our difficulties. Often we were obliged to help each other along by means of our climbing poles.

I must say this for my uncle, that he stuck as close to me as possible. He never lost sight of me, and on many occasions his arm supplied me with firm and solid support. He was strong, wiry, and apparently insensible to fatigue. Another great advantage with him was that he had the innate sentiment of equilibrium--for he never slipped or failed in his steps. The Icelanders, though heavily loaded, climbed with the agility of mountaineers.

Looking up, every now and then, at the height of the great volcano of Sneffels, it appeared to me wholly impossible to reach to the summit on that side; at all events, if the angle of inclination did not speedily change.

Fortunately, after an hour of unheard-of fatigues, and of gymnastic exercises that would have been trying to an acrobat, we came to a vast field of ice, which wholly surrounded the bottom of the cone of the volcano. The natives called it the tablecloth, probably from some such reason as the dwellers in the Cape of Good Hope call their mountain Table Mountain, and their roads Table Bay.

Here, to our mutual surprise, we found an actual flight of stone steps, which wonderfully assisted our ascent. This singular flight of stairs was, like everything else, volcanic. It had been formed by one of those torrents of stones cast up by the eruptions, and of which the Icelandic name is stina. If this singular torrent had not been checked in its descent by the peculiar shape of the flanks of the mountain, it would have swept into the sea, and would have formed new islands.

Such as it was, it served us admirably. The abrupt character of the slopes momentarily increased, but these remarkable stone steps, a little less difficult than those of the Egyptian pyramids, were the one simple natural means by which we were enabled to proceed.

About seven in the evening of that day, after having clambered up two thousand of these rough steps, we found ourselves overlooking a kind of spur or projection of the mountain--a sort of buttress upon which the conelike crater, properly so called, leaned for support.

The ocean lay beneath us at a depth of more than three thousand two hundred feet--a grand and mighty spectacle. We had reached the region of eternal snows.

The cold was keen, searching and intense. The wind blew with extraordinary violence. I was utterly exhausted.

My worthy uncle, the Professor, saw clearly that my legs refused further service, and that, in fact, I was utterly exhausted. Despite his hot and feverish impatience, he decided, with a sigh, upon a halt. He called the eider-duck hunter to his side. That worthy, however, shook his head.

"Ofvanfor," was his sole spoken reply.

"It appears," says my uncle with a woebegone look, "that we must go higher."

He then turned to Hans, and asked him to give some reason for this decisive response.

"Mistour," replied the guide.

"Ja, mistour--yes, the mistour," cried one of the Icelandic guides in a terrified tone.

It was the first time he had spoken.

"What does this mysterious word signify?" I anxiously inquired.

"Look," said my uncle.

I looked down upon the plain below, and I saw a vast, a prodigious volume of pulverized pumice stone, of sand, of dust, rising to the heavens in the form of a mighty waterspout. It resembled the fearful phenomenon of a similar character known to the travelers in the desert of the great Sahara.