HIGH LANDS OF THE EARTH. 209 



our footpath, which had been quite hidden by the intervening mass." There is a limit, 

 however, put to the encroachments of the glaciers. The lower extremities are gradually 

 thawed away in the warm atmosphere of the valleys, so that though pushed forward by 

 the weight of ice and snow accumulated at the upper extremities during the winter, 

 there is a "bound fixed by a perpetual decree," beyond which they cannot pass. 

 Coleridge strikingly alludes to these formations in his Hymn before Sunrise in the Vale of 

 Chamouni ; and science will not quarrel with him for the line which expresses the optical 

 appearance, rather than the philosophical truth. 



" Ye ice-falls ! ye that from the mountain's brow 

 Adown enormous ravines slope amain 

 Torrents, methinks, that heard a mighty Voice, 

 And stopp'd at once amid their maddest plunge! 

 Motionless torrents ! Silent cataracts ! 

 Who made you glorious as the gates of heaven 

 Beneath the keen full moon ? Who bade the sun 

 Clothe you with rainbows ? Who with living flowers 

 Of loveliest blue, spread garlands at your feet? 

 God ! let the torrents, like a shout of nations, 

 Answer ! and let the ice-plains echo, God ! 

 God ! sing, ye meadow-streams, with gladsome voice ! 

 Ye pine-groves, with your soft and soul-like sounds ! 

 And they, too, have a voice, yon piles of snow, 

 And in their perilous fall shall thunder, God ! " 



The glaciers exhibit a singularly diversified aspect, hues varying from the purest white 

 to a blue and green tinge, surfaces resembling in some parts a smooth and polished 

 mirror, and in others a sea frozen when angry and tempest-tost. 



But of all the phenomena exhibited by the highlands of the globe, those of the active vol- 

 canoes are the most peculiar and sublime. The term is derived from Vulcanus, the imaginary 

 god of fire among the Romans, and is applied to those mountains which are the vents 

 of igneous action, ejecting from their sides or summits flame, smoke, ashes, and lava 

 streams. They are in general elevations of a conical form, terminating at the summit 

 with a hollow, called a crater or cup from its shape. Smoke is constantly issuing from 

 the tops of some of these mountains, but the violent paroxysms during which stones are 

 discharged, and torrents of red-hot lava, occur only at distant and irregular intervals. The 

 eruptions frequently issue from several openings or smaller craters, within the superior 

 one, the number and size of which are considerably varied by eras of disturbance. These 

 eras are generally preceded, in some instances for several weeks, by the shocks of 

 earthquakes, or by immense columns of smoke issuing from the volcano about to exhibit 

 explosion, often involving the neighbouring country in darkness. Sounds resembling 

 the successive discharges of a park of artillery are then heard, followed by sudden flashes 

 of flame, and showers of stones. A stream of lava next bursts forth from the side of the 

 mountain, or in a great eruption from the crater, flowing in a sluggish fiery current 

 down the declivities. After the lava ceases to flow, the volcanic ashes, composed of 

 various materials, are thrown out of the summit in immense quantities, sufficient to cover 

 the vicinity for miles. The products of volcanoes differ to some extent, those of America 

 casting out water, and in some instances fish, besides the ordinary materials. It is singular, 

 also, that in the New "World, the active volcanic sites are chiefly continental, while in the 

 Old World they are mostly found in the islands. In both regions, however, they are 

 almost invariably situated near the sea, or some inland collection of water. Upwards of 

 two hundred are known to exist, distributed as follows, according to Professor Jameson's 



statement : 



p 



