KILAUEA, HAWAITI. 181 
been described as a sloping declivity of earth, consists, more cor- 
rectly, of two or three connected slopes. They are intersected by 
fissures from which steam escapes, and the whole surface of two of 
the slopes, to a considerable distance around, is constantly steaming. 
The earth has a egrayish-yellow aspect, yet shows little sulphur on 
the exterior surface: but by turning over the crust, which is a little 
hardened, the under surface exposes a brilliant druse of sulphur crys- 
tals. This crust is formed again, whenever removed, and is due to 
the fact that the temperature at which the rising sulphur vapour con- 
denses, is situated a little below the surface. In obtaining specimens, 
the feet sink to a very uncomfortable depth, and in some places the 
heat is intolerable. ‘There are also fine crystallizations in the fauma- 
roles, though they are generally too brittle to bear handling. 
The other sulphur bank is outside of the crater, half a mile back 
from its northeast edge, where there are fissures and a depression in 
the plain. 
The earth of the above-mentioned declivities had resulted from the 
action of the steam and sulphur gases on the lava rocks. Gypsum 
in thick fibrous plates, alum (sulphate of alumina), blue sulphate of 
copper, and sulphate of ammonia, were also obtained at the same 
banks. Besides, thin siliceous incrustations covered in some places 
the surface of the earth and masses of half-altered lava. 
We continue this account of Kilauea with a brief statement of the 
observations made subsequently by officers of the Vincennes,* in the 
months of December and January. The action was in the main the 
same as has been described, and the general features had not altered. 
The descent from the ledge to the bottom was made by the same 
inclined plane on the northwest side. 
There was but one of the smaller pools, the western, in action. On 
the 16th of December, Dr. Pickering describes it in his Journal as 
heaving up rounded masses of liquid lava, at nearly regular inter- 
vals, toa height of six or eight feet, while smaller jets were thrown 
much higher. At the same time, the large lake was boiling, and 
muttering in its usual style; the brillant surface was compared by 
him to “a fitful network of hghtning on a dark ground.” On the 
31st of December the small pool was entirely inactive, and only a 
* For full particulars reference may be made to the Narrative, by Captain Wilkes, 
vol. iv., chapters iv. and v. 
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