446 NEW ZEALAND. 
lay a small lake about a hundred yards across. The shores of the 
lake were flat and marshy, and clumps of wiry grass and rushes 
covered them, excepting on the western side; here a wide flat beach 
runs back into a small winding valley, from which a shallow streamlet 
flowed to the lake, and over its surface, as well as in the valley, steam 
was issuing from many a pool and crevice. Some of the pools were 
in violent ebullition, and sent up a thick cloud of steam, and though 
generally clear, a few stirred up the mud at bottom by their violent 
action. ‘This ebullition is produced by the escape of some gas, and 
not vapour of water, for the highest temperature observed was 168° 
F. A quantity of the gas was collected, but an accident deprived us 
of it before we had ascertained its composition. As no smell of sul- 
phur was perceived, excepting a very faint trace, and the gas extin- 
guished a taper at once, it was probably nitrogen. 
The rocks and soil up the little valley are variously mottled with 
yellow and reddish incrustations, some of which consist of pure sul- 
phur in layers an eighth of an inch thick. Around the boiling foun- 
tains there were also efflorescences of alum, and on the sides of one 
deeply seated among the rocks, there were small patches of muriate 
of ammonia. ‘The water had no peculiar taste, and but a slight pyro- 
ligneous smell, which probably arose from decayed wood buried in 
the soil. 
The features of the region afforded no evidence that the lake occu- 
pied the crater of a volcano, for there were no volcanic ejections of 
any kind. An area of twenty acres had apparently subsided fifteen or 
twenty feet, as was obvious from a terrace that surrounded the lake and 
the sides of the valley. We may also believe, judging from a line of 
elevated land that encircled the plain, that there had been a more ex- 
tensive subsidence of at least a thousand acres. 
Half a mile before reaching the boiling springs, we passed a larger 
lake of similar features to the one just described. There were no hot 
springs about it, though a smell of sulphur was perceived. About the ~ 
shores there were piles of fallen trunks of trees, appearing like an arti- 
ficial embankment. The trees lay with their tops directed outward, 
and formed a pile twelve feet high above the general surface of the 
plain; we had no means of ascertaining to what depth they extended. 
The region, at some former period, must have been covered with 
forests: and it is probable that the opening of a source of heat or hot 
water prostrated the trees, and gave rise to the lake. There are the 
same evidences of subsidence here as at Waieri. 
