IIu.i.. — Napier io Fidianr/K aud the Tai/po Phtfeaii. 293 



between Taupo Lake as a drainage-area and the draiuaoe of what must be 

 •considered as a part of the Rangitaiki drainage-area. Taupo itself is only 

 1,200 ft. above sea-level, and Karangahape, the high headland on the 

 western side, reaches only 2,379 ft., whilst thirteen miles from the lake 

 (that is, at the 85th milestone), on the^ Taupo Eoad, the height is 2,380 ft. 

 — in other words, the top of Karangahape is on a level with the highest 

 portion of the plateau. 



Taupo as a volcano was apparently much larger than it is as a lake. It 

 would almost seem as if the long, high ridge between the 80th and the 85th 

 milestones formed the eastern side of a great crater in which were many 

 supplementary craters such as are seen to-day as centres of activity in 

 places already named. In the earlier period of volcanic activity the whole 

 comitry from the Kaimanawa Range to the ranges bounded in most places 

 by the Main Trunk Railroad from the latitude of Ruapehu consisted of one 

 immense lava-flow of similar volcanic material, and it is interesting to com- 

 pare the height of some of the conelike hills with the heights of the country 

 along the eastern and north-eastern side of Lakes Taupo and Rotokawa. 

 The western and eastern portions of this once great sea of lava have merely 

 left remnants of Avhat they once were as centres of volcanic movement. 

 Here and there a hot spring remains, but otherwise all active volcanic 

 phenomena have long since disappeared, and the only portion that is really 

 active at the present time is the great central line where so many traces of 

 explosive eruptions are found. 



The great explosive eruption at Taupo and Rotokawa, as also that at 

 Pihanga Mountain, mark the largest and most disastrous of all those that 

 have occurred in the North Island. The pumice thrown out spread over 

 the country, mainly to the eastward, as far as Poverty Bay in the north 

 and Hawke's Bay in the south, Avhilst the middle part of the Island was 

 filled up to a great depth with pumice and other forms of volcanic ejecta- 

 menta. Pihanga' s explosion was towards the north, where the crater- lip 

 was blov/n right out, and is the counter of the Tarawera explosion, which 

 was towards the south ; in fact, the whole face of the country forming the 

 central portion v/as altered by the explosions and the materials thrown out. 

 The water that had drauied into the Rangitaiki from the volcanoes to the 

 south were diverted into the new Taupo crater, which, like Rotomahana, 

 contained many traces of volcanic activity similar to what was seen in the 

 latter bashi after the Tarawera eruption ; and, just as that basin has been 

 slowly filling with water, so in the same manner, following what was an 

 eruption at Pihanga, Taupo, and Rotokawa, immense quantities of debris 

 were deposited over the country for many miles around the centres of 

 explosion, so that watersheds were altered, drainage-areas diverted, swamp- 

 areas replaced which before had been streams and tributaries, and finally 

 provided a drainage-area of considerable size for the new crater that ex- 

 tended for thirty miles or more, and in which thousands of steaming places 

 were to be foimd. 



At this time there Avas no Waikato River such as Ave knoAv it to-day, for 

 the Waikato, from the spot Avhere it leaves Lake Taupo as far as Orakei- 

 korako, merely floAvs through a chasm or rift formed at the time of the 

 Taupo explosion, but filled toAvards the crater-lake Avith pumice that raised 

 the surrounding country several hundreds of feet in height. When the 

 lake tilled in course of time the Avater found a way through the chasm, 

 and loAvered the waters of the lake some 200 ft. or" more. A subsequent 



