224 THE GEOLOGY OF NEW ZEALAND. 
almost innumerable ; some of them shoot up a volume of 
water to a considerable height, and are little, if at all, inferior 
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, all their cooking 
being done in the hot springs, the women’s backs are not 
broken with carrying fuel, and further, from the warmth of 
the ground they were enabled to raise their crops several 
weeks earlier than their neighbours; but, as a counterbalance 
for these advantages, many fatal accidents occur from persons, 
especially strangers and children, falling into these fearful 
caldrons, and being boiled. 
Rotomahana, a warm water lake of considerable size, is 
surrounded with innumerable boiling gulfs; in fact, it is itself 
nothing but a crater, the sides of which are full of action ; it is 
perhaps one of the most singular places in the world, its boil¬ 
ing gulfs, and natural snow-white terraces formed from silicious 
deposits are as wonderful as they are beautiful. Thence to 
Hohake and Rotokawa there is nothing to be seen but jets of 
vapour, and so on to Taupo, where fearful boiling gulfs abound 
at the two extremities of that noble lake, at Rangatira and 
Tokanu. One of the boiling springs at Tokanu possesses the 
property of changing the nature of anything which may be 
placed in it, and converting it into a beautiful silicious sub¬ 
stance of pure white, and this is done without any apparent 
addition of matter ; but if the article be not entirely immersed, 
having only the water flowing about it, then it becomes 
enlarged by a silicious deposit upon its surface. The pro¬ 
cess of thus converting wood into stone is very rapid, and 
in some localities, water does not appear to be a necessary 
agent in accomplishing this change. At Rotorua, large pieces 
of wood are thus lignified by the aid of heated gas, highly 
charged with sulphur, alum, and iron, or other chemical sub¬ 
stances, which penetrates the pores of the wood, and fills them 
up with silex, converting them into agates, and even giving 
them the transparent form of chalcedony. 
Again at Roto-aira, a beautiful lake at the base of the 
Tongariro range, which attains an elevation of 10,236 feet, 
