1867.] COLLIXGWOOD SrLPHrE-SPEIXGS OP FOEirOSA. 383 



two acres of ground, whose desolation forms a very striking con- 

 trast to the verdure on nearly three sides of it. This spot is per- 

 fectly barren, and is filled up with low hillocks of friahle rocks, 

 loose stones, and debris, having the character of a moraine ; it is inter- 

 spersed at irregular intervals with shallow pits or depressions con- 

 taining mud and sand, and sometimes foul muddy water. Prom 

 cracks and fissures in these depressions arose clouds of steam ; and 

 yellow patches of sulphur were visible from a distance. 



At the time of my visit, in the middle of June 1866, there were 

 seven or eight springs in a more or less active condition, from which 

 clouds of superheated steam arose, either by a small round hole or 

 narrow fissure, or by several such apertures. The rushing steam 

 produced a loud noise, like that accompanying the blowing off of 

 steam from a boiler ; and above the fissui^es was a quantity of sub- 

 limated sulphur, adhering to the rock in acicular crystals, forming, 

 about the most active spring, a bright-yellow patch which was 

 visible from a considerable distance. It was no easy matter to 

 reach the sublimed sulphur ; for, on a close approach to the spot, a 

 jet of hot steam'made it necessary to vrithdraw, and warned us that 

 a nearer approach was dangerous. I managed however, with the 

 aid of a stick, to procure some from the crevices, on and around 

 which it was deposited. Host of the springs were dry; but one 

 rose through muddy water, which bubbled up in a series of rapid 

 explosions, carrying the boiling water, sand, and mud 5 or 6 feet 

 high, and splashing it aU around. 



It is evident that the degree of activity of these springs is very 

 variable, and that at the time of my visit they were in a compara- 

 tively quiescent state. The jets of steam were isolated, and a com- 

 paratively small portion of the two acres at which I estimated the 

 area of grey barrenness was in an active condition. Ts^umerous 

 pits, which had evidently at some period sent forth their jets of 

 steam, were perfectly quiet : and stones coated with sulphur scat- 

 tered among them showed their occasional activity. Horeover the 

 edge of the level, where it began to descend down the ravine before 

 mentioned, was covered vdth a thick crust, which had evidently 

 been at one time in a semifluid state, and had slowly flowed, a 

 viscous mass, over the edge, and now had the appearance of dried 

 asphalt. This was doubtless the remains of mud through which the 

 sulphur rose, such as we saw in some comparatively small pools, but 

 which at one time had been in sufficient quantity to rise above the 

 general depression and run over the edge into the ravine. 



The sulphur appeared in aU cases to be deposited in a perfectly 

 pure sublimed form ; nor was there any smell to be detected in the 

 active springs themselves. The steam is laden with the element in 

 a dissolved condition, and deposits it in pure crystals upon any sub- 

 stance with which it comes in contact. The effects produced upon 

 the calcareous rocks were in all cases due to the disintegrating and 

 bleaching power of steam ; and the smell of sulphuretted hydrogen 

 was most perceptible in a spot where the rocks had been disinte- 

 grated, but where there was no sign of present activity. 



