172
THE NEW ZEALAND GAZETTE.
character to those in New Zealand. The geysirs
or boiling fountains of Iceland, long celebrated
for possessing this property in an extraordinary
degree, have, indeed, strong rivals in the puias
and ngawhas of 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
such springs occur, in the immense number of
them, and in the beauty and extent of the sili-
ceous incrustations and deposits, New Zealand
far exceeds Iceland.

In enumerating the principal of these
phænomena, we may begin with—

1. The active craters of Tongariro, which
   are at present in the condition of solfataras
   that may be called the state of repose of active
   craters, and with the hot springs rising on the
   slope and at the base of that mountain.
2. We then pass on to the Tokanu and
   Terapa springs, on the Southern extremity of
   Taupo lake. The principal 'puia' at Tokanu
   is called Pirori, an intermittent fountain whose
   column of boiling water, of two feet in diameter,
   sometimes reaches a height of more than 40
   feet.
3. On the opposite side of Taupo, at the
   Northern extremity of the lake, we again meet
   with hot springs, and with a river of warm
   water called Waipahihi, which, rising in the
   extinct volcanic cone of Tauhara, falls, in a
   vapour-crowned cascade, into Taupo.
4. Descending from Taupo by the outlet of
   the Waikato, we find, on the left bank, in the
   midst of a great number of pools of boiling
   mud, a fumarole called Karapiti, an enormous
   jet of high-pressure steam, escaping with such
   force as to produce a sound like letting-off
   the steam from huge boilers and as to eject to
   a great height sticks, or the like, thrown in
   by the curious traveller. On the right bank is
   another fumarole of similar character, called
   Parakiri.
5. About twenty-five miles below the
   outlet of the Waikato from Taupo, at the 'pa'
   Orakei-korako, both banks of the rapidly-
   flowing river are perforated, in more than a
   hundred different places, by fumaroles and
   boiling springs, most of which are of the
   intermittent kind; and siliceous incrustations
   of beautiful colours decorate the banks of
   the river. Temimi-a-Homaiterangi—the prin-
   cipal geysir—throws up its large column of
   boiling water at intervals of about two hours to
   a height from 20 to 30 feet. An immense
   volume of steam succeeds the jet, and the
   water then suddenly sinks into the basin.
6. At Orakei-korako the line of hot springs
   crosses the Waikato, and continues along the
   foot of the very remarkable Pairoa range on
   the Easterly side of the Waikato. The almost
   perpendicular Western side of this range is
   caused by an immense 'fault' in the volcanic
   plateau, corresponding to a deep fissure in the
   earth-crust, from which sulphureous acid, sul-
   phuretted hydrogen, sulphur and steam, are
   continually escaping, while huge bubbles of
   boiling ash-coloured mud are rising on the
   surface.
7. From the same range, the warm-water
   river Waikite takes its origin. On both sides
   are deep pools of boiling water, on the
   margins of which we discovered most beautiful
   ferns, hitherto unknown, one species belong-
   ing to the genus Nephrolepis, the other to
   the genus Goncopteris These ferns are
   remarkable not only for their elegance, but also
   from the peculiar circumstances under which
   they exist, as they are always surrounded by an
   atmosphere of steam.
8. We now come to the well-known ROTO-
   MAHANA, the most wonderful of all the wonders
   of the Hot Springs district of New Zealand. I
   will not attempt to describe in a hasty lecture
   like this the beauties of this Faëry-land. Who-
   ever has once had the happiness to look into the
   blue eyes of Otukapuarangi and Te Tarata
   can never forget their charms; and whoever
   has stood beside the boiling surf of the Ngahapu
   basin will always retain a vivid impression of its
   terrors. The terraces of siliceous deposit on
   the shores of Rotomahana are unequalled in
   the world, nor is there any thing that even bears
   any resemblance to them.
9. On the Rotorua lake the intermittent
   boiling springs of Whaka-rewarewa are the
   most interesting. Waikite, the principal "nga-
   wha," issues from the top of a siliceous cone some
   20 feet high, and is surrounded by several smaller
   geysirs, boiling mud-pools, and solfataras. At
   intervals of considerable length, sometimes
   extending to many months, all these 'ngawhas'
   begin to play together and form a scene which
   must be most wonderful and beautiful.
   The hot springs of Ohinemutu form
   agreeable bathing places, the fame of which is
   already established.
10. The last in the line are the great
    solfataras on the pumice-stone plateau between
    Rotorua and Rotoiti — such as Tikitere
    and Ruahine.

I will now say a few words in explanation of
these phænomena.

All the waters of the Springs are derived from
atmospheric moisture, which, falling on the
high volcanic plateau, permeates the surface
and sinks into fissures. Taupo—the axis of
which corresponds with the line of the Hot
Springs—may also be considered as a vast
reservoir, from which the lower springs are
supplied. The water, sinking into the fissures,
becomes heated by the still-existing volcanic
fires. High-pressure steam is thus generated,
which, together with the volcanic gases,
decompose the trachytic rocks. The solub'e
substances are thus removed by the water,
which is forced up, by the expansive force of
the steam and by hydrostatic pressure, in the
shape of boiling springs. The insoluble
substances form a residuum of white or red
fumarole clay, of which the hills at Terapa round
Rotomahana and the Pairoa consist.

All the New Zealand hot springs, like those
of Iceland, abound in Silica, and are to be
divided into two distinct classes—the one alkaline,
and the other acid. To the later belong the sol-
fataras characterised by deposits of sulphur, and
never forming intermittent fountains. All the