411 
perfectly clear, transparent water, which in the snow-white in- 
crustated basin appears of a beautiful blue, like the blue turquoise. 
At the margin of the basin I found a temperature of 183° F., but 
in the middle s where the water is in a constant state of ebullition 
to the height of several feet, it probably reaches the boiling-point. 
Immense clouds of steam, reflecting the beautiful blue of the basin, 
curl up, generally obstructing the view of the whole surface of water; 
but the noise of boiling and seething is always distinctly audible. 
Akutina (Augustus), the native who served me as guide, asserted 
that sometimes the whole mass of water is suddenly thrown out 
with an immense force, and that then the empty basin is open to 
the view to a depth of 30 feet, but that it fills again very quickly. 
Such eruptions are said to occur only during violent easterly gales. 
The confirmation of this statement would be of great interest. It 
it be true, then the Tetarata spring is a geyser playing at long 
intervals, the eruptions of whicli equal perhaps in grandeur the 
famous eruptions of the great Geyser upon Iceland. The Tetarata- 
basin is larger than the Geyser-basin, 1 the mass of water thrown 
out, therefore, must be immense. The reaction ot the water is 
neutral; it has a slight salty, but by no means unpleasant taste, 
and possesses in a high degree petrifying, or rather incrustating 
qualities. The deposit of the water is like that of the Iceland 
springs, silicious, not calcareous, and the silieious deposits and in- 
crustations of the constantly overflowing water have formed on the 
slope of the hill a system of terraces, which, as white as if cut 
from marble, present an aspect, which no description or illustration 
is able to represent. It has the appearance of a cataract plunging 
over natural shelves, which as it falls is suddenly turned into stone. 
I had these terraces, which are truly unparalleled in their kind, pho- 
tographed and drawn from various points of view , and the annexed 
1 The basin of the great Geyser is 58 feet in diameter, and has a depth of 
6 to 7 feet. From (he middle of the bottom a cylindrical, shaft-like tube, 12 feet 
wide at the top, but growing narrower as it descends, runs down to a depth of 
751 / 2 feet. I11 the eruptions, which generally take place every 24 hours, the water- 
spout is thrown out sometimes to a height of 100 feet and more. 
