We were soon in the open country, if one may give that name to a vast extent of mounds of volcanic products.

This tract seemed crushed under a rain of enormous ejected rocks of trap, basalt, granite, and all kinds of igneous rocks.
Here and there I could see puffs and jets of steam curling up into the air, called in Icelandic 'reykir,' issuing from thermal springs, and indicating by their motion the volcanic energy underneath.

This seemed to justify my fears: But I fell from the height of my new-born hopes when my uncle said: "You see all these volumes of steam, Axel; well, they demonstrate that we have nothing to fear from the fury of a volcanic eruption." "Am I to believe that ?" I cried.
"Understand this clearly," added the Professor.

"At the approach of an eruption these jets would redouble their activity, but disappear altogether during the period of the eruption.

For the elastic fluids, being no longer under pressure, go off by way of the crater instead of escaping by their usual passages through the fissures in the soil.
Therefore, if these vapours remain in their usual condition, if they display no augmentation of force, and if you add to this the observation that the wind and rain are not ceasing and being replaced by a still and heavy atmosphere, then you may affirm that no eruption is preparing." "But--" 'No more; that is sufficient.