766 The Island of Dominica. [ November, 
gases. At some places it became difficult to breathe, so dense 
was the volume. After passing over about quarter of a square mile, 
densely studded with fumaroles, we entered the gorge seen from - 
a distance. Steep, slippery slopes of partly decomposed trachytes 
here enclosed a narrow stream of water which was found to be 
heated nearly to the boiling point. Sulphuretted hydrogen was 
present in great quantities, and hot steam-jets attacked us from 
the most unexpected quarters. Along the rock-walls we found a 
number of openings, sometimes nearly half a foot in diameter, 
from which either steam or gas issued. 
“ And it bubbles and seethes, and it hisses and roars, 
As when fire is with water commix’d and contending,” 
truly describes what we encountered while slowly climbing 
upward in the gully. From the bottom, through narrow crevices, 
-by way of cylindrical openings, all around us, steam and gas 
threatened to bar farther progress. In. the bed of the hot creek 
the water presented an appearance of violent boiling, owing to the 
rapid emission of large quantities of gas. So thick was the steam 
at this point that it began to interfere with respiration, and at 
times our surroundings were entirely shut out from view for 
several minutes. A large percentage of mineral constituents in 
the water rendered it totally unfit to drink, even when cooled. 
Ascending farther in the gorge, escape from which was negatived 
by barren walls on'either side, we finally reached an elevation of 
about 1200 feet above sea level. Here we found the water cold 
again, trickling in small streamlets over the rocks. We had 
escaped from the region of gas and steam and had passed, at the 
_ same time, the upper limit of present chemical action. Complete 
metamorphosis, produced by long-continued decomposition, had 
placed these rocks beyond the influence of atmospheric agents. 
Burned out, not now taking part in the phenomena of the imme- 
diate vicinity, they remain as mute witnesses of the forces which 
_ there must have been at work for ages. 
_ To our satisfaction we were enabled to find in some fragments 
= of fresh and partly decomposed trachyte, the solution of the 
Striking scenes witnessed. Minute crystals or irregular fragments 
A i of pyrite impregnate the rock throughout a definite zone. 
-~ — Weight the quantity of this pyrite may amount to about twenty 
| per cent. Moisture in conjunction with atmospheric air will 
= readily decompose this mineral, a process which is accompanied — 
