SUMMING UP THE RESULTS.

Nelson Evening Mail, Volume XX, Issue 144, 18 June 1886, Page 2

SUMMING UP THE RESULTS.

The special correspondent of the Evening Post telegraphed from Rotorua on Wednesday last : —

From telegrams received here it is evident that many people who are acquainted with the topography of the district have got mixed regarding what has occurred, and even at Ohinemutu one may get a variety of decisions. The first telegrams „nnounc- • ing that Ohinemutu was either totally destroyed or damaged, and that even Taurangu was endangered, have never been got completely out of the minds of a great many people. It must be stated, to get a starting point for our resume, that Ohinemutu is wholly unimpaired ; not one chimney is shaken down, not a pane of glass broken. That this could be true of any place situated only about 15 miles, as the crow flies, from the centre of the eruption, may seem strange to the inexperienced, yet if consideration is given to what was known of the I action of volcanoes, it ia not at all extraordinary. There are more than 20 extinct points of volcanic eruption on the Auckland isthmus. Yet the larger proportion of the soil is pure clay, without the semblance of scoria, ash, or volcanic dust. A spectator might have stood with perfect safety within a nr'b of Mount Eden and watched it blaze, and in its quieter moments, as adventurous toui\*lo do at the famous Hawaiain volcano, and as tourists will do here should Tarawera keep up its j fires, he might ascend the hill and look into [ and even descend the yawning gulf. Tbe area covered by this eruption is unusually large, and the impulse necessary to send the stones so far as they have gone must have been tremendous ; but if anyone takes the trouble to make the calculation he will see that the force necessary to propel a stone weighing half a pound 10 miles is inconceivable as being disclosed in any volcanic eruption. The dust clouds borne on the wind may do serious injury over a wide area, and the mud cloud, when its weight is allowed for, has passed much further than would have been conceived. Such an eruption as this happening in any thickly populated district would have been terribly fatal, as we see by its effect on the scattered native villages. But as it is, apart from the sad loss of life among the Maoris, and the temporary destruction of the feed for cattle on the East Coast farms and the irreparable loss of the Terraces, the injury to the existing settlements in these districts is not so great as might have been expected from such a catastrophe, and will soon be got over. Where it has injured.' Rotorua most is by shaking confidence in the stability of the ground, because of the suspicion that what has happened at Rotomahana may occur at Rotorua which is in almost an equal ferment, This is true in one sense, but on the other hand the eruption of Tarawera is, so far as we know, the only event of the kind for thousands of years, and Ohinemutu may share its fate in thousands more. The chances are not worth calculating, except to bring clearly to the mind of the reader that, wide as the area is that has been affected by this eruption, its origin and power of mischief is strictly local and confined to the area embraced in the channel of country extending from Tarawera mountain to Lake Okaro, a distance of about 10 miles, and say about 10 miles round this centre. Towards Kaiteriria the deposit does not extend so far as this, but in the direction of Te Teko it is said to have been destructive at a distance of 30 miles. There is, however, great exaggeration in many of the reports about these deposits, and it may be safely doubted if they will prove permanently deleterious to vegetation at a point beyond ton miles, and the area may probably be set down at very much less. To enable persons who have no knowledge of the district to understand the situation, a few words of explanation may be necessary. Rotorua or Ohinemutu, the headquarters of tourists, and the place where the Government sanatorium has been established, is situated on Lake Rotorua, and abounds with hot springs and small geysers, with some traces of terrace formation at Whakarej warewa, a native village ten miles from Rotorua. Lake Tarawera lies nine miles in a S.E. direction, the road to it passing Tikitapu Lake and Lake Itotokakahi. The village of AVairoa stood on a small arm of Tarawera, and was the nearest point of embarkation to cross Tarawera for the purpose of reaching Rotomahana, a small lake south of it. and the site of the famous Terraces. Tlie south shore of Tarawera was skirted nearly six miles, and then an arm called Te Ariki, bending southwards two miles, brought the tourists to a small creek about a mile and a half long, carrying off the How from Rotomahana. Te Terata, the White Terrace, was situated at the Tarawera end of Rotomahana, and perhaps about four miles from Tarawera Mountain, an eminence 1 961 feet high to the eastward. The shores of Rotomahana were honeycombed everywhere with steam jets or fumarolos, and exhibited in the highest degree of intensity all those peculiar forms of volcanic action which have made the Lake district famous, The buried native settlement of To Ariki stood on the arm of Tarawera bearing that name ; it was. here that the lake

guides lived who fleeced Europeans visiting the Terraces. On the morning of lOfch June, about 2 o'clock, the side of TaraWera Mountain, next Rotomahana Lake, was blown out amid a fierce storm of the elements, including thunder, lightning aud earthquakes. On another peak of the same mountain another enormous crater was opened, sending forth showers of ash in the direction of Te Teko. What caused these unusual disturbances in mountains which had never before shown signs of volcanic activity is a matter of speculation ; but undermining and subsidence through geyser action around Eotomahana appear a very simple and probable explanation. This violent eruption probably shattered the steam pipes of Rotomahana geysers, r.nd letting the waters of the lake down id Lravy streams, caused a terrific steam expansion, and the vomiting of an immense, cloud of mud, which was caught in the terrific cyclone produced by these disturbances, and carried across the south shore of Tarawera, -smothering Wairoa native village in its journey, and spreading over the east shore of Rotorua as far as Taheke on Lake Roto-iti. It has been suggested that mud is of too great a specific gravity to be wind-borne so far, and that the mud-shower must be accounted for merely by the wetting of the earth with steam, but this theory takes no account of the hurricane prevailing at the' time, evidence of which is given in uprooted trees and the dashing of the mud with such force agaiust buildings, trees, and posts that it stripped off leaves and was plastered in solid layers which gave rise to the evidently erroneous impression that the great lumps had travelled for miles. The theory also offers no explanation of the extensive deposits of dry earth and ash to the southward of Rotomahana, large portions of which must have been driven out by the steam and borne across the volumes of steam at all times hanging over the lake. Attendant upon these eruptions was the formation of a large number of fumaroles or steam, volcanoes in Rotomahana, and four in the fern valley leading to lake Okaro, where the disturbance stops. Seven fumaroles were also opened upon different parts of Tarawera Mountain. The most startling feature of the eruption is the immense body of earthy matter which it has deposited, and the evenness with which it is spread. This totals many millions of tons. The country covered is as smooth as a table, every irregularity being rounded off to a perfectly even surface. If ' we adopt the theory of subsidence in Tarawera Mountain as the cause of the eruption — and there is evidence of this at Rotorua. where the site of the ancient village is now submerged in the lake — the occurrence will, and should, I think, prevent the aggregation of any large population upon land subject to such treacherous, insidious, and irresistible agencies. At the same time it is probable -that one year hence people who are now uneasy with these reflections, will have reconciled their minds to take the risk, by reflecting that it is not worth while calculating upon events that happen only once in a geological period. The immediate damage .then consists in the loss of seven Europeans and 97 natives, the destruction of five native villages, two hotels, two houses, and the mission hall, and the overspreading of the country desciibed with debrix. The future • danger arises from the slipping down of the thick mud deposits under rain action. This, however, is probably over-estimated, as the settlement will be very gradual.