THE GEYSERS. 
117 
head of a cauliflower. On reaching the top of 
this siliceous mound, I looked into the per¬ 
fectly circular basin *, which gradually shelved 
down to the mouth of the pipe or crater 
in the centre, whence the water issued. This 
mouth lay about four or five feet below the 
edge of the basin, and proved, on my afterwards 
measuring it, to be as nearly as possible seven¬ 
teen feet distant from it on every side; the great¬ 
est difference in the distance not being more than 
a foot. The inside was not rugged, like the out¬ 
side; but apparently even, although rough to the 
touch, like a coarse file: it wholly wanted the 
little hillocks and the efflorescence of the exterior, 
and was merely covered with innumerable small 
tubercles, which, of themselves, were in many 
places polished smooth by the falling of the water 
upon them. It Was not possible now to enter the 
basin, for it was filled nearly to the edge with 
water the most pellucid I ever beheld, in the 
centre of which was observable a slight ebulli¬ 
tion, and a large, but not dense, body of steam* 
which, however, increased both in quantity and 
density from time to time, as often as the ebulli¬ 
tion was more violent. At nine o’clock I heard 
* To compare great things with small, the shape of this 
basin resembles that of a saucer with a circular hole in its 
middle. 
