As they advanced, the encircling hills thrust their projecting spurs further and further into the narrowing plain, their slopes became steeper and more rugged, and rocks began to crop out here and there with increasing frequency through the lessening soil. A corresponding change of course occurred in the character of the landscape; it grew increasingly picturesque and wild at every step, and at length the travellers found themselves at the mouth of a narrow rocky boulder- strewn gorge bounded on either side by titanic masses of volcanic rock, rugged and moss-grown, with little patches of herbage here and there, or an occasional stunted pine growing out of an almost imperceptible fissure. The only signs of life in this wild spot consisted of a diminutive musk-ox here and there cropping the scanty herbage half-way up the apparently inaccessible height in spots from which it appeared equally impossible for the creature to advance or to retreat. Plunging into this defile, the travellers advanced with steadily increasing difficulty, the boulders with which their path was strewed growing ever larger and more numerous until at length the narrowing road became completely choked with them, and the only mode of progression was that of a slow, toilsome, dangerous scramble. Still the pair pushed resolutely on, every minute hoping that the difficulties of the journey would come to an end, and every minute less willing to turn back and again encounter the obstacles already surmounted. At length the path became so narrow that one enormous boulder sufficed to completely block the way, whilst the perpendicular rocky walls of the chasm towered so far aloft that only the merest thread of sky was visible; the air grew chill and damp, and so deep a twilight gloom pervaded the place that it was difficult to distinguish any object more than half a dozen yards distant. The weary travellers looked at each other in dismay. Was this to be the ineffectual ending of that long and toilsome scramble through the ravine? There was just one single narrow crevice between the huge boulder which blocked their way, and one of the precipitous walls which pressed so closely in upon them--a crevice left by the irregular shape of the block, and affording barely space enough for a man of robust proportions to squeeze himself through--and they determined that, before retracing their steps, they would at least satisfy their curiosity so far as to creep through this crevice and see what lay on the farther side. The baronet with some little difficulty squeezed through first, and his exclamation of astonishment quickly took the colonel to his side.