THE NEW ZEALAND GAZETTE. 169

time to devote to the volcanic formations which,
from their great extent and the remarkable and
beautiful phænomena connected with them,
render the Northern Island of New Zealand,
and especially the Province of Auckland, one
of the most interesting parts of the world.

VOLCANIC FORMATIONS AND PHEΝΟΜΕΝΑ.

Lofty trachytic peaks covered with perpetual
snow, a vast number of smaller volcanic cones
presenting all the varied characteristics of vol-
canic systems, and a long line of boiling springs,
fumaroles, and solfataras, present an almost
unbounded field of interest and, at the same
time, a succession of magnificent scenery.

It is only through a long series of volcanic
eruptions, extending over the tertiary and post-
tertiary periods, that the Northern Island has
attained its present form. It would be a
difficult task to point out the ancient form of
the antipodean Archipelago the site of which
is now occupied by the Islands of New
Zealand. I must confine myself to a
simple indication of the events which have
given this country the form it was found to
have by the South-Sea Islanders on their
arrival, many centuries ago, from the Samoan
group, a form in all main respects the same
as is now before our eyes.

The first volcanic eruptions were submarine,
consisting of vast quantities of trachytic lava,
breccia, tuff, obsidian, and pumice-stone,
which, flowing over the bottom of the sea,
formed an extensive submarine volcanic
plateau. The volcanic action continuing,
the whole mass was upheaved above the level
of the sea, and new phænomena were deve-
loped. The eruptions going on in the air in-
stead of under the sea, lofty cones of trachytic
and phonolithic lava, of ashes and cinders,
were gradually formed. These eruptions,
breaking through the original submarine layers
of trachytic lava, breccia and tuff, raised them,
and left them, as we now find them, forming a
more or less regular belt round the central cones,
and having a slight inclination from the centre
outwards. These belts I shall have occasion to
refer to under the name of "tuff-craters," or
"cones of tuffs," or "craters of elevation."

In the course of time the volcanic ac-
tion decreased, and we must now imagine
that tremendous earthquakes occurred—that
parts of the newly-formed crust gave way and
fell in, forming vast chasms and fissures, which
are now occupied by the Lakes, Hot Springs,
and Solfataras.

Thus we now find in the central part of the
Northern Island an extensive volcanic plateau
of an elevation of 2000 feet, from which rise
two gigantic mountains, Tongariro and
Ruapahu. They are surrounded by many
smaller cones, as Pihanga, Kakaramea,
Kaharua, Rangitukua, Puke Onake, Hauhanga.
The natives have well named these latter, "the
wives and children of the two giants
Tongariro and Ruapahu;" and they have a
legend to the effect, that a third giant, named

Taranaki, formerly stood near these two—but
quarrelling with his companions about their
wives, was worsted in combat, and forced to fly
to the West coast, where he now stands in
solitary grandeur, the magnificent snow-capped
beacon of Mount Egmont (8270 feet). These
are the three principal trachytic cones of the
Northern Island.

By far the grandest and loftiest of
the three is Ruapahu, whose trun-
cated cone, standing on a basis of about
25 miles in diameter, attains a height of
9 to 10,000 feet above the level of the sea—about
3000 feet of which is covered with glaciers and
perpetual snow. Ruapahu, like Taranaki, is
extinct. Tongariro alone can be said to be
active. I was enabled to distinguish five
craters on Tongariro, three of which are to a
certain extent active. Steam is always issuing
from them, and the natives state that from the
principal crater, called Ngauruhoe, on the
top of the highest cone of eruption (7500 feet),
occasional eruptions of black ashes and dust
take place, accompanied with loud subterranean
noises. I may remark, that the shape of the
cone is changing, the western side, for instance,
having, during the great earthquake at Wel-
lington, in 1854, fallen in, so that the interior
of the crater is now visible from the higher
points in the Tuhua district on the Upper
Whanganui. The remarkable fact, that snow
does not rest upon some of the upper points of
the Tongariro system, while the lower ones
are covered all the winter through, shows that
those parts are of a high temperature.

(I had no opportunity myself of ascending
Tongariro, but I have met with the following
interesting account of an ascent of the highest
cone of eruption by Mr. H. Dyson, which was
communicated to the New Zealander by A. S.
Thomson, M.D.:--*

Mr. Dyson's Account of his Ascent of Tongariro,
In the month of March, 1851, a little before sunrise
I commenced my ascent alone, from the north-western
side of the Rotoaire lake. I crossed the plain and as-
cended the space to the northward of the Whanganui
river. Here I got into a valley covered with large
blocks of scoriæ, which made my progress very diffi-
cult. At the bottom of the valley runs the Whanga-
nui river. After crossing the river, which at this
place was then not more than a yard broad, I had to
ascend the other side of the valley, which, from the
unequal nature of the ground, was very tedious, and I
kept onwards as straight as I could for the top of the
mountain. At last I came to the base of the cone,
around which there were large blocks of scoria which
had evidently been vomited out of the crater, and had
rolled down the cone. The most formidable part of
my journey lay yet before me, namely the ascent of
the cone, and it appeared to me from the position
where I stood that it composed nearly one fourth of
the total height of the mountain. I cannot say at
what angle the cone lies, but I had to crawl up a con-
siderable portion of it on my hands and feet, and as it
is covered with loose cinders and ashes, I often slid
down again several feet. There was no snow on the
cone or the mountain, unless in some crevices to which
the sun's rays did not penetrate. There was not on
the cone any vegetation, not even the long wiry grass
which grows in scanty patches up to the very base of
the cone. The ascent of the cone took me, I should
think, four hours at least; but as I had no watch, it is
possible from the laborious occupation I was at, that
the ascent of the cone looked longer than it was.