196 Mr. Alison's Narrative of an Excursion to the 



obliged to jump from block to block, and to climb over some 

 with the hands and feet. We were again much annoyed by 

 the snow, which was in thick masses between the currents 

 and blocks of lava. The whole of it was frozen hard, forming 

 a surface like glass, which made it extremely difficult to cross, 

 as we were unprovided with proper shoes. 



After some exertion we reached a spot called La Cueva de 

 Nieve (the Cave of Snow), which is 11*098 feet above the 

 level of the sea, and 2*141 feet above the foot of the Peak. I 

 entered this cave by an aperture near the roof, which is about 

 twelve feet high and eight or nine wide ; and was let down to 

 the bottom by means of a rope fastened round my waist. It 

 appears to be formed of large blocks of an earthy and cellular 

 lava, containing large crystals of felspar, which have run 

 together in a half-fluid state, and formed a roof of stalactitic 

 lava, which gradually curves towards the sides. The length 

 in one part, I think, is 120 feet, and about 20 wide. The 

 bottom is filled with water, which is strongly frozen over 

 near the sides, but in the middle it is only covered with a 

 slight skin of ice. The water in some places is ten or twelve 

 feet deep, but in others it is less. At the bottom of it I ob- 

 served a plant that looked like a species of Fucus, but I was 

 not able to get it up for closer inspection. Under the entrance 

 was a wreath of frozen snow and several square blocks of ice, 

 and from the roof hung innumerable icicles, and a quantity of 

 nitrate of potash and a kind of ammoniacal salt. At the further 

 end was an immense bunch of icicles, forming the rough out- 

 line of the human figure, which the guides called the Man of 

 Ice : it has been in the same state for many years, which is a 

 proof of the low temperature of that part of the cave which is 

 at a distance from the external air. I am inclined to think 

 that the ice in this cave is produced by the water being im- 

 pregnated with nitre, and the porous nature of the lava, which 

 conjointly may cool the water down to the freezing point. 

 Water boiled here at 185°, and the bulb of a thermometer, 

 inclosed in silk and wetted with aether, fell 9° in one minute; 

 and a surface of aether, 0*25 of a line in depth, evaporated in 

 the same space of time. 



In forty-five minutes after leaving the cave we arrived at a 

 small plain of pumice called the Rembleta, situated 11*721 feet 

 above the sea. This plain appears to have been the ancient 

 crater of the Peak, previous to the formation of the present 

 cone, which rises in the middle of this plain to the elevation 

 of 467 feet. The ascent up this cone, or Sugar-loaf as it 

 is called, is the most difficult and laborious part of the journey. 



The 



