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The Pamphlet Collection of Sir Robert Stout: Volume 67

Premonitory Signs

Premonitory Signs.

A sense of security had thus—owing to the decreasing action of the volcanic forces—been induced in the inhabitants of the district, and no fears or expectation of any violent outburst hindered the gradual settlement of the country in the neighbourhood of the springs. For ages past the Maoris had selected their villages in the immediate vicinity of the boiling waters, induced thereto by the facilities offered to culinary operations, the additional warmth to be gained in an I atmosphere pervaded by hot vapours, or the pleasures of a plunge into the ever-warm baths. As European settlement extended, the neighbourhood of the most famous hot springs was fast becoming occupied. Hotels and other accompaniments of civilization were a frequent adjunct to the Maori village, built frequently in the midst of steaming solfataras and fumaroles; and but for the accident of difficulties in connection with the Maori titles, many more Europeans would ere this have occupied the district. The far-famed terraces of Rotomahana were year by year attracting larger crowds of visitors to view their wonders, and had not the eruption occurred a hotel would ere this have been erected in their neighbourhood on the very site of what is now a roaring crater. It is a matter of hearty thankfulness that the eruption occurred at the time of year when the visitors had nearly all left the district, or we might have had to add to the already long list of killed, the names of others from all parts of the world. And yet, notwithstanding the universal opinion as to the decadence of the volcanic forces, there were signs in the air shortly preceding the eruption, which, if properly understood, would have told that some changes of moment were taking place—which should have acted as a Laming to those who now lie buried under the ashes at Te Ariki, Rotomahana, and Wairoa. Some few of these premonitory signs may be mentioned.

Although quite unconnected with the late eruption, a change of a somewhat remarkable nature in Lake Rotokakahi is here recorded, as showing that the volcanic forces were active, though unnoticed except in the locality, for some time past. In April, 1881, there was a sudden and unaccountable rise in the waters of the lake; and again, in October, 1883, without any warning whatever, the water page 20 suddenly rose for 4ft., causing a flood to rush down the Wairoa Stream into Lake Tarawera, whilst at the same time the olive-green colour of the lake was changed to a turbid, muddy appearance. The water fell the following day as suddenly as it rose. The cause of these phenomena is obscure; but, as they occurred at a time of year when little rain falls, and as no visible stream supplies Rotokakahi, they must have been subterranean, and evidently connected with volcanic action.

In March, 1880, the coasts of the Bay of Plenty, and indeed, far outside it, were strewn with millions of dead fish of all descriptions, and as these showed no signs of disease, it follows that probably they were poisoned. The line of the great fissure passes south-westerly from White Island under the sea towards the shore of the bay, and if, as is possible, an eruption of gases, even on a small scale, was to take place anywhere along this line, the result would doubtless be that fish in great quantities would be destroyed. We have no direct evidence as to whether this was the case; but it is a reasonable inference in the absence of any exact information as to other causes.

Very nearly a year previously to the eruption of Tarawera the crater-lake of White Island disappeared, leaving its bed quite dry, and it remains so to the present time. Changes, however, in the level of the lake were not uncommon, and have been noticed for many years past; but, as far as can be learnt, it has never been so completely dry before.

For some time previously to the eruption the hot springs in the neighbourhood of Mount Edgecumbe and Te Teko were noticed to be much more active than usual, and the water of a higher temperature,

Next in order, and much nearer both in time and locality, was a change in the fountain which supplied the waters of the White; Terrace of Rotomahana. It is a well-known fact that the water in the great caldron on top of the terraces was affected in a remarkable manner by the wind. This is so clearly described by Captain Gilbert Mair, F.L.S., in his paper, "Notes on the Influence of Atmospheric Changes on the Hot Springs and Geysers in the Rotorua District" (Trans. N.Z. Inst., Vol. IX., p. 27), that it may be transcribed here. He says: "Perhaps the most singular instance of atmospheric influence is in the case of Te Tarata, the White Terrace of Rotomahana. The great crater, which is about 90ft. in diameter, is usually full of deep-azure-blue-coloured water, occasionally boiling up 10ft. or loft.; but when the keen south wind, or tonga, blows, the water recedes, and you can descend 30ft. into the beautifully- page 21 encrusted crater, which remains empty until the wind changes, when it commences to refill at the rate of 3ft. or 4ft. per hour, boiling and roaring like a mighty engine. When the crater is almost full, grand snow-white columns of boiling water, 20ft. in diameter, are hurled 60ft. into the air. Blue waves of boiling water surge over the shelllike lips of the crater, and fall in a thousand cascades over the alabaster terraces." This was not by any means an uncommon event; but Mr. Josiah Martin, F.G.S., who was staying at the terraces in the month of November, 1885, was lucky enough to witness an eruption of the waters on a far grander scale, a description of which he has been good enough to supply as follows: "From the 19th to the 21st November, 1885, the wind was from the west to south-west, with rain-squalls and a falling barometer. The water from the caldron was flowing down the terrace as usual. On the 22nd the wind changed to south, with clear, calm weather, and a rising barometer. The activity in the caldron ceased, and the waters began to recede within the basin. By 6 a.m. the basin was empty, the water having retired into the tube below. At 12 noon, the activity had again commenced, and the water was rising within the tube. At the same time it was noticed that the barometer was falling. At 1 p.m. the action of the water was feeble, but agitated, and rising slowly within the basin. By 4 p.m. the action had become vigorous, and dense clouds of steam were given off; and at 5 p.m. the basin was half full, the water violently agitated. Suddenly a deep boom was heard and felt on the upper terrace, like an underground explosion, and the water in the basin was instantly lifted into a huge dome, from out of which shot vertically with enormous velocity a glistening fountain, the top of which was lost to sight in the dense mass of accompanying vapour, the broken waters falling in heavy showers around. This was succeeded by another similar outburst; hut the height attained was not so great. The Maoris, observing this eruption from the lake, were greatly surprised, and said it was the most violent they had ever seen. By 8 p.m. the activity had ceased, and the water had retired about 1ft. within the basin, the barometer rising at the same time. On the 23rd, a calm, clear morning, the basin was empty, but the tube full, with very slight ebullition, in which state it continued till evening, when the terraces were dry and the barometer failing. On the 24th, the early morning was calm and clear, with a rising barometer. Very suddenly, at 6 a.m., the water was violently active. Two explosions occurred, each throwing up the water more than 150ft., accompanied by a dense column of steam rising rapidly to a height of 800ft. or 1,000ft., page 22 followed by several smaller eruptions ejecting the waters to 100ft. By 8 a.m. the eruption had ceased, and the basin was quiet but full, and the barometer rising. A slightly-increased activity, with constant overflow down the terraces, was noticed at 4 p.m. From the 24th to the 28th November the activity was normal, with a constant overflow and high barometer, the winds being light and variable, with bright, clear days, cold nights, and hot weather. During the first four (lavs the overflow occurred with falling barometer and low readings, and ceased when the barometer was rising. During the subsequent period activity was renewed with rising barometer and continual higher readings; and from these and previous observations I consider north and north-east winds, with heavy weather, most favourable for excessive overflow, and that action has generally ceased, and the basin been emptied, with a south wind and bright, clear weather." It is to be regretted that Mr. Martin's beautiful mezzotint picture of this eruption, enlarged from an instantaneous photograph, cannot be reproduced here; but the drawing attached (Plate No. 1) gives some idea of what it was like. As respects the Tarawera eruption, this minor one is adduced as evidence of the increasing activity and changes taking place on the line of the great fissure. It is noticeable that the Maoris who have always lived near Rotomahana never saw (or presumably heard of) any occurrence on such a scale before.

On the 10th March, 1886, the writer was at Wairakei, near Taupo, a place celebrated for its geysers, hot springs, and boiling-mud pools, and where the hydro-thermal action is displayed in a variety of forms not often seen. On visiting one of the geysers called the Twins, it was found to be in great commotion, throwing up the water to a height of some 20ft., a thing it had not been known to do for a long time previously.

Reference has already been made to the fact that the grand mountain of Ruapehu, situated at the southern end of the Taupo Zone, and which bears on its shoulders a deep mantle of perpetual snow, had until quite recently been supposed to be a volcano whose fires had ages ago died out. But on the ascent of the southern peak, Pari-te-tai-tonga, by Mr. W. Cussen in 1884 the lake lying in the crater-like hollow near it exhibited some differences from ordinary basins of cold water which inclined Mr. Cussen to suggest the possibility of the water being warm, if not hot. It was impossible to descend the steep snow-bound walls to decide the question, and it therefore remained in abeyance until March of the present year, when Mr. L. Cussen, in the execution of his triangulation, again made the ascent on two occasions. All doubt was then set at rest by his find- page break
Eruption of White Terrace—22nd Nov 1885.

Eruption of White Terrace—22nd Nov 1885.

From a Photograph by Mr J. Martin, F. G. S.

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Ruapehu From Ohinepanco

Ruapehu From Ohinepanco

page 23 ing the crater-lake to be steaming, and the waters showing that turmoil of surface common to hot-water lakes, whilst the snow had been melted for some way up around the margins, particularly so on the side where the prevalent westerly wind had blown the heated vapour onto it. Mr. Cussen states that it is impossible to get down to the level of the lake, on account of the steepness of the snow-covered sides, without the aid of appliances, which his other duties precluded his providing. There is no doubt, however, that the agitated waters and the steam rising from the surface prove that thermal action is still going on. On the 16th April and 23rd May last he observed from the lowlands to the west a column of steam rising up to a height of about 300ft. above the mountain-top, over the crater-lake, and at other times since then has seen more or less vapour at the same place when the surrounding atmosphere has been quite clear.

Mr. Dunnage, a young officer of the Survey Department, who performed the difficult feat of ascending the southern peak on the 8th June (almost in midwinter), reports: "The snow was in a favourable condition for climbing, but it was necessary to cut each footstep for the last thousand feet. The height given by the barometer, which was very low that day, was 10,200ft. [The true height is 8,878ft.] Large quantities of steam were issuing from the little lake in the centre of the crater, nearly 1,000ft. below us; but was all condensed before reaching the top. The cold was very severe."

Major Scannell, residing at the north end of Taupo, in answer to inquiries, says, "There can be no doubt about it. The steam was noticed from here, and I saw it myself rising from the mountain about three weeks previous to the eruption, but nothing whatever since."

The Maoris have no tradition of any activity, either volcanic or thermal, ever having been noticed on Ruapehu, nor have the European settlers ever seen or suspected anything of the kind previous to the twelve months before the eruption of Tarawera. The only prior indication of anything of the kind which might have led to a suspicion of the true character of the mountain was the fact that the waters of the Whangaehu River, flowing from a point high up in its side, were of a peculiar nature—strongly acid and flavoured with sulphur, of a milk-white colour, and extremely unpalatable either to man or beast; but no weight was attached to this as indicating that the mountain contained thermal springs on its top.

To anticipate somewhat the order of events, it may be stated that Mr. A. B. Wright, when crossing this river at the usual place on the 20th July, found that a change had taken place. The water was quite page 24 clear, and no longer turbid and milky as of yore; and be was informed by Mr. McDonald, who lives near, that this change had occurred since the eruption; and, further, that Messrs. Maunsell, Cowie, and Sutherland noticed on the 5th July that the south-east face of Ruapehu, all along the ravine out of which the Whangaehu rises, was enveloped in clouds of steam. These well-authenticated facts all tend to show that changes were taking place at the southern end of the line of fissure for some little time previous to the eruption.

At a point further to the north, at Toka-anu, on the south shore of Taupo, the site of numerous hot springs, geysers, and fumaroles, one of the latter suddenly burst out and threw up mud and water for several yards round; but it returned to its usual state at the time of the eruption, a fortnight after. The ejection of water from these places, however, is not an uncommon event, though mud is seldom cast out. Further north, but still on the line of fissure, at Wairakei, Mr. Cullen, the gentleman in charge, informed Major Scannell that a new hot spring bad burst out shortly before the eruption.

And now, approaching more nearly to the time and place of eruption, a few circumstances will be noted as witnessed by a reliable authority, which had better be described in his own words. Dr. T. S. Ralph, of Carlton, Melbourne, who was a member of the last expedition to the terraces at Rotomahana, has with great kindness furnished the following account of what he then saw: "I arrived at the Wairoa on Monday, the 31st May, and on the following morning (the day being fine throughout) I went down to Tarawera Lake in company with five other visitors, all desirous of seeing the terraces. The descent from the hotel (McRae's) is a very steep one, and I was the last of my party to approach the boat which was to convey us over the lake. I found myself cut off from my companions by a sudden wash or overflow on the footpath at the place of embarkation, and escaped a wetting by getting on to a slight elevation. After a short time I was enabled to join my companions, who were preparing to take boat. On speaking about the occurrence, I was told that this was the second wave which had swept over the footpath. The Native boatmen and Sophia, our guide, seemed much disinclined to proceed, urging that such a phenomenon had not been seen on the lake, at any rate, for some fifteen years. However, we proceeded on our voyage, and I noticed that the sedges all along the shore showed how high the wave had been, and this rise indicated a height of from 9in. to 1ft. It was visible for a long distance on the south side of the lake, passing on to Rotomahana. The weather was calm, and there was no page 25 agitation of the surface of the lake. At the landing-place, Te Ariki, we heard from the resident Maoris that the water had been noticed to rise there also. I consider the direction of the (earthquake?) wave to have been from the north. After visiting the White Terraces we went to the Pink Terrace, where our guide pointed out that the mud from one of the geysers had been projected fully twenty or twenty-live yards from the crater quite recently, for it was soft; and all this was pointed out as quite unusual. I could not judge if the activity was greater than usual, but on arriving at this terminal point of our expedition I began to feel uneasy and to realize a sense of danger connected with all around me. . . . On mentioning the fake-wave the next morning at breakfast (2nd June)—it was to Mr. Bainbridge, I believe, one of the victims of the eruption—he said that at the time I had indicated he was riding towards Wairoa, and heard a report like the boom of a cannon: I did not gather whence it came. On our return to Wairoa the whole evening was devoted by our crew and the villagers to a discussion of the events of the day—the wave, the spectral canoe, the apparent activity exhibited at the Pink Terrace, and the dead chief lying unburied near Mr. Haszard's house—all indications (to them) of impending danger."

Dr. Ralph and his companions were the last Europeans to see the incomparable beauties of the White and Pink Terraces, so soon to be shattered into a myriad pieces, and strewn in minute fragments over the neighbouring country. The wave on Tarawera Lake, the eruption of mud at the Pink Terrace, were the forerunners of the impending catastrophe. The wave was due to an earthquake (which it is right to say was not noticed at the Wairoa) or to a subsidence of the shore, marking perhaps, the first significant fracture of the rock-masses superimposed on the imprisoned steam, which shortly after was to work such desolation, and deal destruction to the unfortunates living in the vicinity, a destruction involving the death of a whole tribe with the exception of one man, and numbering its victims, European and Maori, at 111. Rangiheua, an old chief of Tuhourangi, had, a few days previously to the 10th June, removed with some ten or twelve members of his tribe to Puai and Pukura, two little rocky islets situated in the middle of Rotomahana Lake, for the sake of bathing in the healing waters of the terrace-baths and the numerous other thermal springs there situated. He and his people were consequently the witnesses of the first signs of the catastrophe which occurred on the 10th; but, alas! the knowledge of what those first signs were is lost with the old chief and his relations, who must have been some of the earliest victims on that terrible night.

page 26

The enumeration of the above-mentioned facts goes to prove that along the whole line of fissure, from White Island in the north to Ruapehu in the south, a more than usual degree of activity was displayed some time prior to the eruption; and if we had records of the various other springs, &c., along the line, possibly other evidence might be adduced. It is not the purpose of this account to deal with the Tarawera eruption as bearing on the volcanic activity as exhibited in various other parts of the world during the past few years, or to trace any connection between the local outburst and lines of volcanic force which several writers suppose to be connected with that of New Zealand; but it is significant that seismic and volcanic activity have marked the last few years as quite exceptional in that respect. We can only hope that the wave of activity has passed, and that New Zealand, having contributed its share, will now regain its usual state of quiescence.