The outer field had been steadily encroaching upon the inner, breaking the edges of both, until the points of junction were to be traced by a long line of fragments forced upward, and piled high in the air.  Open spaces, however, still existed, owing to irregularities in the outlines of the two floes; and Daggett hoped that the little bay into which he had got his schooner might not be entirely closed, ere a shift of wind, or a change in the tides, might carry away the causes of the tremendous pressure that menaced his security.  It is not easy for those who are accustomed to look at natural objects in their more familiar aspects, fully to appreciate the vast momentum of the weight that was now drifting slowly down upon the schooner.  The only ray of hope was to be found in the deficiency in one of the two great requisites of such a force.  Momentum being weight, multiplied into velocity, there were some glimpses visible, of a nature to produce a slight degree of expectation that the last might yet be resisted.  The movement was slow, but it was absolutely grand, by its steadiness and power.  Any one who has ever stood on a lake or river shore, and beheld the undeviating force with which a small cake of ice crumbles and advances before a breeze, or in a current, may form some idea of the majesty of the movement of a field of leagues in diameter, and which was borne upon by a gale of the ocean, as well as by currents, and by the weight of drifting ice-bergs from without.  It is true that the impetus came principally from a great distance, and could scarcely be detected or observed by those around the schooner; still, these last were fully aware of the whole character of the danger, which each minute appeared to render more and more imminent and imposing.  The two fields were obviously closing still, and that with a resistless power that boded destruction to the unfortunate vessel.  The open water near her was already narrowed to a space that half an hour might suffice to close entirely.

“Have you set that nearest island by compass, Daggett?” asked Roswell Gardiner, as soon as he had taken a good look around him.  “To me it seems that it bears more to the eastward than it did an hour since.  If this should be true, our inner field here must have a very considerable westerly set.”

“In which case we may still hope to drift clear,” returned Daggett, springing on board the schooner, and running aft to the binnacle, Roswell keeping close at his side.  “By George! it is as you say; the bearings of that island are altered at least two points!”

“In which case our drift has exceeded a league—­Ha! what noise is that?  Can it be an eruption of the volcano?”

Daggett, at first, was inclined to believe it was a sound produced by some of the internal convulsions of the earth, which within, as if in mockery of the chill scene that prevailed without, was a raging volcano, the fierce heats of which found vent at the natural chimneys produced by its own efforts.  This opinion, however, did not last long, and he gave expression to his new thoughts in his answer.