CATARACTS, AND INUNDATIONS. 



seconds, and between them the water boils in the same manner ai 

 in the other basons. 



Towards the upper end of the valley, there was a very curious 

 hole, which attracted much of our attention. It seemed to have 

 served at some former period as the well of a fountain, but was of 

 of an irregular form, and from four to five feet in diameter. It 

 was divided into different hollows or cavities at the depth of a 

 few feet, into which we could not see a great way, on account of 

 their direction. A quantity of steam issued from these recesses, 

 which prevented us from examining them very closely. We were 

 stunned while standing near this cavern, and in some measure 

 alarmed, by an amazing loud and continued noise which came from 

 the bottom. It was as loud as the blast of air forced into the fur- 

 jjace from the four great cylinders at the Carron iron-works. 



We could discover no water in any of the cavities; but we found 

 near the place many beautiful petrifactions of leaves and mosses. 

 They were formed with extreme delicacy, but were brittle, and 

 would not bear much handling ; their substance seemed chiefly 

 argillaceous. 



We perceived smoke issuing from the ground in many places in 

 the higher parts of the valley, much further than we extended our 

 walks. I am sorry to say we left many things in this wonderful 

 country unexamined ; but we were checked in our journey by many 

 circumstances, which allowed us neither the leisure nor the oppor- 

 tunity for exploring every part of it as we could have wished. The 

 substances deposited near the different springs seemed to me, in, 

 general, a mixture of calcareous and argillaceous earths; but near 

 one spring, not far from our tents, there seemed to be a slight de- 

 position of siliceous matter. To the eye it resembled calcedony; 

 but with its transparencey, it had not the same hardness, and, if 

 pressed, would break to pieces. The water you have analysed 

 came from this spring, and we were obliged to take some care in 

 filling the bottles ; for though gradually heated, they would break 

 when the water was poured into them, if it had not been previ- 

 ously exposed to the air for some minutes in an open vessel. 



The water of this spring boiled, as in most of the others, in a 

 cauldron four or five feet broad. I do not recollect to have seen 

 any of it ever thrown up above a foot, and some meat we dressed in 

 it tasted very strongly of sulphur. 



