450 
THE GEOLOGY OF NEW ZEALAND. 
trees which formerly grew there. At Mahurangi there are 
several warm springs which, from their vicinity to Auckland, 
will eventually be much frequented. 
The next centre appears to be Waka-ari, White or Sulphur 
Island, which with its neighbour Moutohora, Whale Island, 
are still in action ; the latter indeed is chiefly filled with solfa- 
tara and hot springs, but the former is a volcano rising out 
of the sea, from the crater of which a volume of smoke is 
always ascending, visible at a great distance ; large masses 
of sulphur are there produced, and the varied form and cha- 
racter of the molten rocks of this crater are very interesting. 
The grand centre of volcanic action extends from White 
Island to Kotorua, and thence by Taupo and Tongariro to 
Wanganui, a distance of nearly two hundred miles, forming 
a continuous line across the entire width of the island. The 
number of solfatara, boiling gulfs, and mud pools in that 
line is extraordinary, they are seen in every direction — in 
the forest, in the plain, and in the water ; a large number 
are concentrated at a place called Tikitere, and a most extra- 
ordinary assemblage of them is found at Ohinemotu, which 
renders that place one of the most remarkable in New 
Zealand. At Paeroa, near the Waikato, there is one of the 
largest of these mud pools, it is from sixty to a hundred feet 
wide, in the centre first an enormous bubble arises, which 
gradually increases in height and size, and at last becomes a 
jet of mud eight or ten feet high, with several smaller ones 
around it ; this is thrown up in large masses on the sides, 
where it dries, and assumes a cubical form, readily separating 
into laminge of different thickness, which bears a close resem- 
lance to slate, and, perhaps, in this mud vortex is to be seen, 
on a small scale, what was once the state of a large portion 
of the earth’s crust during the formation of slate. 
At Orakokorako, on the Waikato, the boiling springs are 
almost innumerable ; some of them shoot up a volume of 
water to a considerable height, and are little, if at all, in- 
ferior to the Geysers of Iceland ; a village is placed in the 
midst of them ; the reason assigned for living in such a 
singular locality was, that as there is no necessity for fires. 
