Page:Our New Zealand Cousins.djvu/327

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Appendix.
311

lashed with a fury that baffles description—roaring, cannonading, screeching, driving into the air at one spot columns of steam such as might be generated in the boilers of a leviathian steamship, and from another orifice in the same crater send out black volumes of smoke and showers of stones, is a spectacle that can only lose in magnificence by any attempt to convey an expression of it in words. I feel that I dare not attempt to do it justice. Fortunately, from the configuration of the ground a full view may be obtained of a most extensive area of country.

With regard to the volcanic eruption, Dr. Hector believes that the earthquake shocks caused by the outbreak of Tarawera mountain, ruptured the steam-pipes in the Rotomahana geysers and let in the water of the lake upon the subterranean heat, resulting in the generation of enormous quantities of steam and the ejectment of the mud at the bottom of the lake. He doubts, however, whether the eruption has been of a character which produces the formation of lava. He thinks rather that the outburst on Tarawera was caused by the rupture of the sealed cap which was previously impervious to steam. The stones resembling scoria were, he thinks, formed by heat produced in steam and not through liquefaction of the rock by intense heat. From a number of specimens I had collected on the scoria hills at the back of Rotomahana, he selected one which, from its characteristics, gave indications of lava. The rest were mostly pieces of terrace formation and a small piece of obsidian. As to the chance of a further eruption, Dr. Hector hesitates to pronounce any decided opinion. He believes, however, that the chief danger at present is from the mud. He says the danger from the shifting of recent deposits is well recognized.