NOTES AND QUERIES. 
191 
tracliytic 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 phenomena were developed. The eruptions going on in the 
air instead of under the sea, lofty cones of trachytic and phonolithic lava, of 
ashes and cinders, were gradually formed. These eruptions, breaking tlu-ough 
tiie 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 vol- 
canic action 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 two thousand feet, from which rise two 
gigantic mountains, Tongariro and Ruapahu. They are surromrded by many 
smaller cones, as Pihanga, Kakaramea, Kaharna, Rangitukua, Puke Onake, 
Haulianga. The natives have well named these latter, "the wives and 
children of the 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 (eight 
thousand two hundred and seventy feet). These are the three principal 
trachytic cones of the Northern Island. 
By far the grandest and loftiest of the three is Ruapahu, whose truncated 
cone, standing on a basis of about twenty-five miles m diameter, attains a 
height of nine thousand to ten thousand feet above the level of the sea, about 
three thousand feet of which is covered with glaciers and perpetual snow. 
Ruapalm, like Taranaki, is extinct. Tongariro alone can be said to be active. 
Dr. Hoehstetter distinguished five craters on Tongarii-o, 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 (seven thousand five hundred feet), occasional eruptions of 
black ashes and dust take place, accompanied with loud subterranean noises. 
It may be remarked that the shape of the cone is changing, the western side, 
for instance, having, during the great earthquake at Welhngton 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. 
There is an interesting account of an ascent of the highest cone of eruption 
by Mr. H. Dyson, communicated to the "New Zealander," 1851, by A. S. 
Thomson, M.D. Mr. Dyson, in 1851, and Mr. Bidwell, in 1839, are the only 
Europeans who have ascended the highest cone of Tongariro. 
The second active crater of the Tongariro system, at the top of a lower cone 
north of Ngauruhoe, is called Ketetahi. According to the natives the first 
eruption of this crater took place simultaneously with the Wellington earth- 
quake of 1854. From Taupo lake Dr. Hoehstetter saw large and dense 
volumes of steam, larger than those from Ngauruhoe, emerging from the Kete- 
tahi crater. The third active point on the Tongariro system is a great solfatara 
on the north-western slope of tlie range. The hot sulphurous springs of that 
