A4A NEW ZEALAND. 
soil of volcanic cinders. At the summit we left the dry fern beds of 
the exterior, and passing over a narrow lip, plunged down the decli- 
. i 
AIS 
EXTINCT VOLCANO, POERUA. 
vity among the forest trees of the crater. By a very steep descent over 
loose earth, gradually changing to coarse fragments of lava, we soon 
reached the cool shady depths of this seat of ancient fires. Here were 
huge blocks of lava, fifty to a hundred cubic feet in size, lying loosely 
piled on one another; and among them large trees were thickly 
planted, whose massy foliage shut from view the height from which 
we had come, and all but a few points of the blue sky over head. The 
soil was damp, and nourished numerous succulent plants; but there 
was no standing water, although in a region of frequent rains. Many 
of the trees appeared to be as old as the forests of the plains, and 
nothing indicated very recent action in the volcano. 
We estimated the breadth of the crater across the summit at fifteen 
hundred feet. The break on the west extends rather more than half 
way to the base of the cone, but we may infer from the exterior view, 
that when formed, it opened through to the very bottom, and that 
the lavas which then escaped by this opened passage, together with 
subsequent accumulations of cinders and volcanic fragments, have 
restored it to half its original height. ‘The plain surrounding the vol- 
cano was strewed with blocks of lava, which the natives had collected 
together into heaps, to prepare the land for tillage; but on the west, 
where the gorge opens, the fragments so completely covered the plain 
that improvement was not practicable. 
Small pieces of porous lava were very abundant towards the bottom 
of the crater. The large blocks are comparatively compact, or very 
sparingly cellular. 
No continuous stream of lava was observed, as the region is covered 
with soil or the loose blocks alluded to. Near the foot of Ahuahu, at 
one of the villages of ‘Taiamai, the rock appears in place for a short 
distance. Near Poerua, the ground in some places sounded hollow 
as we walked over it; and there is a small tepid spring in its vicinity, 
from which, as I was informed, bubbles of gas are continually escaping. 
