192 
THE GE0L0QI3T, 
solfatara are often visited by the natives on account of the relief they ex- 
perience in respect to their cutaneous diseases. 
A grand iin])rcssion is made upon the traveller by those two magnificent 
volcanic cones, lluapahu, shining ■with the brilliancy of perpetual snow, Tonga- 
riro, with its black cinder-cone capped with a rising cloud of white steam : the 
two majestic mountains standing side by side upon a barren desert of pumice, 
called by the natives Oue-tapu, and the whole reilected as by a mirror by the 
waters of Lake Taupo. 
Lake Taupo is twenty-two English miles long in the direction from Terapa 
to Tapuaeliariiru, and sixteen broad. It is surrounded by elevated pumice- 
stone plateaus, above two thousand feet above the sea, and seven hundred feet 
above the lake. The Waikato river, taking its rise from Tongariro, flows 
through the lake, traversing the pumice-stone plateau on either side. In 
accordance with the names already proposed for the middle and lower Waikato 
Plains, the Taupo country will form tlie Upper Waikato Basin. 
It is one of the most characteristic features in the structure of the Northern 
Island, tliat from the sliores of Taupo Lake an almost level pumice-stone plain, 
called Kaingaroa Plain, stretches at the foot of the East Cape range, with a 
very gradual descent to the coast between Wliakatane and Matata. A plain 
which, though now presenting a sterile appearance, will, I hope, at no distant 
day, be converted into fine grassy laud, capable of supporting large flocks of sheep. 
In a simQar way, a higher volcanic plateau, consisting of tracliytic tuff and 
breccia, and various other volcanic rocks, stretches in a more northerly direction 
to the east coast, between Maketu and Tauranga, the farthest extremities of 
which reach even to the Auckland district. On one side of Hauraki Gulf, the 
Coromandel range is covered with trachytic breccia, and again, on the west 
coast, the same rocks form the coast-range from Manukau to Kaipara. This 
extensive plateau is intersected by many deep vaUeys, the sides of which are 
characterized by a succession of remarkable terraces. The same plateau is also 
broken in many places by more or less regular trachytic cones, from one tliou- 
sand to three thousand feet high. If we take a wider view of the geological 
features and the pliysical outline of these just described high plains and plateaus 
consisting of regular layers of trachytic rocks, breccia, and tuff, we shall find 
that the steep cones of Ruapaho and Tongariro rise from the centre of a vast 
tuff-cone of extremely gradual inclination, the basis of which occupies the whole 
country from sliore to shore — from east to west — having a diameter of one 
hundred sea-miles, and forming the largest cone of tuffs, or in other words 1 he 
largest crater of elevation in the wiiole world. 
Intimately connected with the described volcanic phenomena of the active 
and extinct volcanic mountains are tlie solfataras, fumaroles, and hot springs. 
They are found in a long series, stretching across the country in a north-nortli- 
east direction, from the active crater Ngauruhoe in the Tongariro system, to 
the active crater of White Island (Whakari), occupying the chasms and fissures 
already referred to. 
There is only one other place in the world in which such a number of hot- 
springs are found that have periodical outbursts of boiling water, that is in 
Iceland, the well known geysirs of which are of precisely similar character to 
those in New Zealand. Although there may be no single intermittent spring 
in New Zealand of equal magnitude with the great geysir in Iceland, yet in the 
extent of country in which these springs occur, in the immense number of 
tliem, and in the beauty and extent of the siliceous incrustations and deposits, 
New Zealand far exceeds Iceland. 
On the southern extremity of Taupo lake, at Tokanu, is Pirori, an inter- 
mittent fountain of boiling water, two feet in diameter, sometimes reaching a 
height of more than forty feet. On the opposite side of Taupo, at the northern 
