THE GEYSERS, HOT SPRINGS, AND TERRACES OF NEW ZEALAND. 377 
the contour of the hill, and the countless fumaroles, solfataras, 
and geysers bear witness to the enormous activity at work be- 
neath. The surface is everywhere warm to the touch, and its 
foothold is treacherous in the extreme ; and further evidence of 
activity may be obtained by a tour of inspection over the 
ridge, where a puff of steam rises from the soil as it crumbles 
beneath our tread, and very thick soles are necessary to protect 
our feet. The hill from which this geyser rises covers an area 
of about 1,000 yards by 500. It slopes on the s.w. into Roto- 
mahana, or the Warm Lake, and on the n.e. into Rotomakariri 
— the Cold Lake. 
The great basin of Terata is situated at a height of nearly 
eighty feet above the level of the lake, and 300 yards from the 
outer edge of the lowest terrace (fig. 2). The reservoir is nearly 
circular, of about ninety feet diameter, and of a depth variously 
estimated at from twenty to forty feet. It is nearly surrounded 
on its inner side by a lip or edge, about six feet wide. Through 
the dense overhanging steam, the deep azure water of the 
cauldron may be seen (see Analysis No. 1). It is always hiss- 
ing and boiling, and possesses a temperature varying from 210° 
to 214° F., according to its activity. It is so quiet at times that 
a daring adventurer can walk around its lip, or even descend a 
few feet into its nearly empty basin ; but it will suddenly, and 
with terrific violence, break into activity, and, throwing up an 
enormous column of water, fill its basin to overflowing, and 
perhaps forcibly eject the whole contents in one convulsive 
eruption, throwing the water to a height of forty or fifty feet, 
to the certain destruction of any one who has dared to come 
within reach of its scalding fountain. 
Two-thirds of the basin is enclosed by the hill-side, and an 
island of harder rock stands midway in the opening. This 
affords shelter for the spectator, as well as an elevated position 
from which to observe the eruptions or to view the terrace. 
The siliceous deposit which forms the terrace extends from 
the lip or edge of the basin over a large plateau, and then 
descending in three sections, forms a lower plateau, which has a 
frontage to the lake of about 200 yards. 
The upper plateau receives the very newest deposits, and 
resembles a small field of ice covered with a few inches of snow. 
The spectator feels that it is almost sacrilege to tread upon and 
crush this beautiful crystallized frost-work. The sun’s rays, 
decomposed by these delicate crystals, with sparkling iridescence 
glisten in fairy splendour. Below the beautiful curves form- 
ing the edge of this plateau, and sloping outwards, are rounded 
masses of snow-like sinter; below these again are several pools 
of hot water of the richest cobalt hue, or sparkling like sapphire, 
which, reflecting the overhanging festoons, light them with deli- 
