VOLCANO OF KIRAUEA. 



but it required the greatest caution, as the stones and fragments 

 of rocks frequently gave way under our feet, and rolled down 

 from above. The steep which we had descended was formed of 

 volcanic matter, consisting apparently of light red and grey vesi- 

 cular lava, lying in horizontal beds, varying in thickness from one 

 to forty feet. In a few places the different masses were rent in 

 perpendicular and oblique directions, from top to bottom, either by 

 earthquakes, or by other violent convulsions of the ground. After 

 walking some distance over the plain, which in several places 

 sounded hollow beneath our feet, we came to the edge of the great 

 crater. Before us yawned an immense gulf in the form of a 

 crescent, about two miles in length from the north-east to south- 

 west, one mile in width, and 800 feet deep. The bottom was covered 

 with lava, and the south-west and northern parts were one vast 

 flood of burning matter. Fifty-one conical islands of varied form 

 and size, containing as many craters, rose either round the edge 

 or from the surface of the burning lake. Twenty- two constantly 

 emitted either columns of grey smoke or pyramids of brilliant 

 flame, and at the same time vomited from their ignited mouths 

 streams of lava, which rolled in blazing torrents down their black 

 indented sides into the boiling mass below. The existence of 

 these conical craters led us to conclude that the boiling cauldron 

 of lava did not form the focus of the volcano, but that this liquid 

 mass was comparatively shallow, and the basin which contained 

 it separated by a stratum of solid matter from the great volcanic 

 abyss, which constantly poured out its melted contents through 

 these numerous craters into this upper reservoir. We were 

 further inclined to this opinion from the vast columns of vapour 

 continually ascending from the chasms in the vicinity of the 

 sulphur banks and pools of water, for they must have been pro- 

 duced by other fire than that which caused the ebullition in the 

 lava at the bottom of the great crater ; and also by noticing a 

 number of small vents in vigorous action high up the sides of the 

 great gulf, and apparently quite detached from it. The streams 

 of lava which they emitted rolled down into the lake, and mingled 

 with the melted mass, which, though thrown up by different 

 apertures, had perhaps been originally fused in one vast furnace. 

 The sides of the gulf before us, although composed of different 

 beds of ancient lava, were perpendicular for about 400 feet, and 

 rose from a wide horizontal ledge of solid black lava, of irregular 

 width but extending completely round. Beneath this ledge the 

 sides sloped gradually towards the burning lake, which was, as 

 nearly as we could judge, three or four hundred feet lower. It 

 was evident that the large crater had been recently filled with 

 liquid lava up to this ledge, and had, by some subterranean 



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