BY THE REV. J. E. TENISON-WOODS, P.G.S., &C. 



709 



fumes were rising in intermittent clouds with a faint murmur like 

 boiling water. The width of one of these pits was about 20 yards, 

 and of the other about 40 yards, but I only judged of these from a 

 distance : they were perhaps 100 yards apart. 



As I have already stated, the interior of the walls was tinted 

 with all sorts of colours, very much like a furnace or a kiln on a 

 gigantic scale. They were composed of loose ashes and scoriae, but 

 sometimes molten together and twisted like splashings of furnace 

 clinker on a large scale. There were great bosses of sulphur and 

 other minerals, probably gypsum or felspar or lime, but it would 

 be a very long business to describe the whole of the appearances 

 along the sides of the crater. The whole of this heterogeneous 

 mass of rock — as Sefior Centeno well expresses it — is broken up 

 and confused by landslips, deep cracks, and loosening of the strata, 

 produced sometimes by the rains, by interior emanations and 

 •explosions, or finally by great earthquake shocks, to which the 

 crater must be exposed at periods of unusual activity. 



The following is an analysis given by Sefior Centeno of the 

 water of the yellow lake : — 



Analysis. Grammes. 



Sodium chloride ... ... ... ... 15 -941 2 



26-9889 

 The above was the result of an examination of the solid contents 

 obtained by evaporation of one litre of the water. I have two 

 other analyses from different authors, which difter only slightly 

 from the above. 



