1818.] Henderson's Journal of a Residence in Iceland. 305 



pervades the whole of this desolated region. The gloom of the 

 lake is greatly augmented by the small black islands of lava with 

 which it is studded ; and the pillars of vapour ascending in 

 different parts from the surface of the water remind the observer 

 that the destructive element, which has been the tremendous 

 cause of the surrounding ruin, still lingers there, and may again 

 wake to activity. The lake is reckoned to be about 40 miles in 

 circuit, but is shallow from the floods of lava that have been 

 poured into its basin. 



The next morning they resumed their journey towards the 

 sulphur mountains, passing over considerable tracts of lava and 

 volcanic sand, till having arrived in their immediate vicinity, the 

 increase of the exhalations, and the heat and unsoundness of 

 the surface, obliged them to advance with caution over the more 

 indurated parts. With all their care, the feet of their horses 

 occasionally broke through the crust, forming holes through which 

 the vapour issued in great abundance. On either side lay vast 

 beds of sulphur, covered with a thin crust, composed of aluminous 

 efflorescences, which being removed, a thick bed of pure sulphur 

 appeared, through which the steam issued with a hissing noise. 

 The sublimation of the sulphur is caused by the ascent of this 

 vapour, and its abundance and purity depend considerably on the 

 porosity of the subjacent soil. The tract which goes by the name 

 of the Sulphur Mountain is about five miles in length and one 

 mile in breadth, extending between the volcanoes of Krabla and 

 Leirhnukr, and joining the ridge by which these two mountains 

 are connected. The surface is very uneven, displaying large 

 banks of red clay and sulphur, the crust of which is variegated 

 with tints of blue, yellow, and white. 



After overcoming with great difficulty the labour, and escaping 

 the dangers of the ascent, they arrived suddenly on the edge of 

 an abrupt descent of more than 600 feet, at the bottom of which 

 lay a row of 12 large cauldrons of boiling mud, roaring, splashing, 

 and sending forth immense columns of dense vapour. By a cir- 

 cuitous route, among numerous boiling hot quagmires, they at 

 length arrived close to the springs. Excepting two which lie a 

 short distance from the rest, they are all crowded into one vast 

 chasm in the lava. Some of them remain stationary, but roar 

 terribly, and emit much steam ; others boil violently, and splash 

 their black muddy contents round the orifice of the pit, while two 

 or three jet at intervals to a height of from five to 15 feet. 



From this extraordinary scene they passed along the margin 

 of a stream of lava, covered with pumice and volcanic sand to 

 the base of Krabla ; and with much difficulty succeeded in mak- 

 ing their way over the pumice sand and slippery clay which form 

 the side of the mountain. After an hour's climbing, they arrived 

 at a vast hollow, forming the remains of the crater, in the middle 

 of which lay a circular pool of black liquid matter at least 100 

 feet in diameter. Nearly about the centre of the pool is an aper- 

 ture from which a vast body of fluid, consisting of water, sulphur, 



Vol. XU. N° IV. U 



