[Read before the Auckland Institute, 30th November, 1885.]
On Sunday, October 11th, a slight shock of earthquake was felt about 10 a.m., and seeing we had had several shocks lately no particular notice was taken of it; but on Tuesday morning everybody's attention was directed to vast clouds of steam and smoke which were arising from the sea in a N.N.W. direction. On the preceding evening, at 11 p.m., many natives and others saw a vivid flash of light, and heard a report like thunder in the direction of the Huga Group of islands. On the matter being communicated to His Majesty, it was determined that the Sandfly should be sent to ascertain the bearings and extent of the volcano. Accordingly at noon the Sandfly left the Port of Nukualofa, having on board the Rev. S. W. Baker, the Premier, wife, and family; the Rev. J. B. Watkin and son, Dr. Buckland, and several other gentlemen; the Chief Tugi and several natives.
As the Sandfly neared the spot the scene was most magnificent, great volumes of steam, of carbonic and sulphurous gas, &c., being shot forth from many jets out of the sea, in a direct line of over two miles, extending in a northerly direction, to the height of 1,000 feet and more, then expanding themselves in all directions, in clouds of dazzling whiteness, and assuming the most fantastic shapes; sometimes presenting themselves as a mountain of wool, the tips of which were fringed with gold, caused by the rays of the setting sun, then again occasionally forming into a large cauliflower head of snowy whiteness,
backed by clouds of intense darkness formed of dust and ashes mixed with watery vapour, which the wind was carrying down for miles on the distant horizon. As the heavier matter kept continually falling, it gradually raised in height the new-made island; and as the cloud of pulverulent matter became thinner and thinner at its extremities, it assumed a light brown colour, forming clouds of volcanic dust which, no doubt, would be carried thousands of miles away, and repeat (if the theory be a correct one) the red sunsets of the volcanic action of last year in distant parts of the Pacific: and, strange to say, on the third and fourth evenings after the bursting out of the volcano, the same red sunsets as were seen last year were again noticed. The size of this mass of volcanic matter was immense; at one time it could not have been less than some thousands of feet at its base, and, piercing into the air to a great height, was distinctly seen thousands of feet above the clouds, and at one time a streak of sable colour passing across its centre made the whole mass present a most picturesque and grand sight. This great mass of accumulated gas, steam, and volcanic substance, was continually augmented by fresh explosions, bursting forth from three large and a number of minor jets. These jets, and especially the largest one, would suddenly rise forth like a solid wall of dark matter, in shape something similar to the three fingers of a man's hand, but always of a more or less conical form, and at times bearing a striking resemblance to the Pinus pinaster and Pinus sylvester, thus forcibly calling to mind the historical stone-pine of Pliny the Younger, mentioned in his letter to his friend, the historian Tacitus, in connection with the eruption of Mount Vesuvius in A.D. 79. The black clouds were small at first, and only appeared at considerable intervals, and gradually became larger and more frequent, 1 ½ to 3 ½ minutes expiring between each eruption, but still retaining their perpendicular character; and, after rising to a considerable height, their sides would sometimes fall quickly into the sea, causing clouds of steam to arise, whilst the centre would topple over and form itself into clouds of white gaseous and vapourous matter, presenting itself like a huge bunch of Prince of Wales' feathers; and what was most singular, many of these dark cauliflower eruptions had a spiral movement, always turning in the same direction from north round by the west to the south, and right against the wind. As the shades of evening approached and the night came on, the matter discharged by the volcano no longer appeared a huge mass of clouds of snowy whiteness but in the form of clouds of greyish matter and sooty blackness. We were somewhat disappointed in there being no signs of fire; many watched during a great part of the night, anxious to catch the first glimpse of the lurid flame, but were doomed to disappointment.
As the first light of morning appeared, we commenced to approach near the grand scenery of Nature's last wonder, having kept during the night at a distance of seven or eight miles. As daylight appeared, it was soon evident that the volcano had lost none of its activity, but instead of there being so many jets as on the previous night, several of them at the southern end of the line of jets had coalesced and formed themselves into one immense submarine chasm, and the rays of the rising sun shone upon the mass of vapoury matter and made it appear most beautifully golden. Having a good breeze behind us, we ventured to approach nearer than we would have otherwise done, and we were duly rewarded for our trouble, for we found that an island had already been formed some three to four miles in length, one in width, and attaining a height of about 40 feet at its highest part, which was around the crater on the N.W. side, and gradually shelving away from this until it lost itself in the sea. The length of the island was probably increased by a black mass, which we believe to be floating pumiceous matter; and it was also seen that a reef extended from it in a N.E. direction, from the surface of which various jets of steam were arising. The eruptions were now very rapid, and in one instance there were no less than four huge eruptions in three minutes. Although one of these large masses was ejected considerably over 1,000 feet, yet it only took 16 seconds in reaching that height; in fact, having timed many of the eruptions, we found that notwithstanding they went to a greater or less height they invariably took from 12 to 16 seconds. Some of these eruptions must have contained hundreds of tons of matter; and several times, just as the eruption reached its height, great spouts would be seen, which appeared to be huge waterspouts, and continued increasing until they were lost in the mass of gaseous vapour. These eruptions continued with very little interruption until 8.30 a.m., when to the surprise of everyone they suddenly ceased—and it is worthy of note that up to this moment there had been a constant column of smoke, &c., discharged from the volcano—and the strong wind, carrying away all the clouds of steam and gaseous matter, presented to our view the whole of the land, with a distinct crater formed on the S.E. end of the same, the back part of which was considerably higher than that at the water edge, which appeared to be only a foot or two. Dr. Buckland and others were of opinion that this was the exact moment when it emerged from being a submarine volcano to that of an ordinary volcano. As we were not more than one mile from it, we had a splendid and magnificent view, and we were led to judge that the crater from the size of the base of the column was at least two miles in circumference. Our attention was drawn to a white spot which appeared on the western slope of the crater, which, after careful examination with our glasses, we concluded was a bird which had tried to fly across
the volcano, and was suffocated by its fumes. So eagerly were we examining the crater that we neglected to notice the dangerous position in which we were, for, to our surprise, the vessel, notwithstanding the breeze we had, made but little headway, and for a few minutes it looked as if the current would draw us into the volcano. However, after several minutes of suspense the breeze increased, and we were soon out of danger, which was clearly manifested by the vessel shooting ahead as she drew out of the current; and it is fortunate for us that we escaped when we did, for the volcano commenced action shortly afterwards, and fragments of heated stone were hurled aloft to a great height and then fell, together with showers of cinders, splashing into the sea at some distance from the edge of the new-formed island. The matter ejected now seemed to be of a more solid nature than that which had been previously thrown out by the volcano. This, together with the fact that very little steam was now seen around its base, although over the surface of the island the steam still continued to rise in small jets, seems to be sufficient proof of the correctness of the conjecture formed by Dr. Buckland, that it had now passed from a submarine volcano to that of a volcanic island, and although no fire presented itself, yet it continued all day belching forth such solid matter, accompanied with clouds of gases; for, after the completion of the crater, the enormous upheavals of cinders, mud, and dust, &c., increased not only in rapidity, but also in height, ten occurring in twelve minutes; sometimes a second and third would arise before the first had fallen. This continued for about three-quarters of an hour, when the eruptions became less frequent, but increasing in height, towering aloft from 8,000 to 10,000 feet, or perhaps even considerably higher, and the light flocculent clouds of vapour, which separated themselves from the main mass and floated away in the air, presented a most enchanting spectacle, and between the eruptions the island was more or less visible. But to describe the various shapes which these eruptions of gaseous matter assumed would be impossible. It certainly is one of the grandest efforts that even volcanic nature has ever made, and one of the most beautiful sights that mortal man has ever been permitted to behold. On that evening, about 7.30, the first signs of fire were visible, and all through the night at intervals it sent up quick darts of lurid light, sometimes of a burning red, and at other times a bluish or pinkish flame; the reflection on the clouds, as some large flash burst forth, presented all the features of sheet lightning, and the light always appeared in the same place, and on one occasion four or five flashes occurred at the same instant; but whether it was due to the condensed clouds of vapour being highly charged with electricity, or whether it was caused by fire being ejected from the volcano, it is difficult to determine. And
thus we were permitted to see the various forms through which it passed, from that of a submarine volcano, with its dashing boiling stream, to that of a volcanic island ejecting its heated stones, mud, cinders, &c.
This volcano forms one of the linear series of volcanoes which run in a direct line from the Culibras to Fonualei, bearing N. by E. ¼ E. and S. by W. ¼ W. magnetic.
There are no less than six volcanoes in this belt, including the recent one, and all in the Friendly Islands Group, viz.: Sandfly Rock, Tofua, Kao, Wesley Rock, Late, and Fonualei. This is the order in which they stand from the recent volcano. Of these Kao is the highest, and is 5,000 feet in height, but has not been active for many years; its crater is on the N.E. side, and the shape of the island is that of a large cone. The next in height is that of Tofua, a large razor-back island, with the crater on the N.E. side. This is 2,800 feet in height, and has been slightly in action only a few months ago. The next is Late, 1,790 feet, and is still in action. Then comes Fonualei, which in some parts is about 600 feet, but has not been active for more than thirty years. The last volcano is that of Wesley Rock, which sprang up as a submarine volcano in the year 1858, and was discovered by the John Wesley; it is now about 400 feet, and occasionally very active. It is somewhat singular, and perhaps worthy of notice, that the mouth of all the craters of these volcanoes has an easterly aspect. But whether the present volcano has burst out on a part of the Culibras reef we are not prepared at present to say, the Culibras reef being marked on our chart more to the S.W. And a circumstance of considerable interest in connection with the Culibras reef is that it has fallen and risen several times during the last few years: at times a long reef being distinctly visible above the water, and at other times not a trace of it to be found; such is the statement of authorities who went with the express purpose of ascertaining and locating its position; and on one occasion, after the lapse of a year or so, the reef was found to have shifted a distance of no less than three miles. The position of the present volcano is N.N.W. from Nukualofa, 48 miles; from Huga Tonga, N.N.W. ¼ W., 14 miles; from Huga Haapai, N. by W. ¾ W., 15 miles; and its latitude and longitude, from bearings taken on board the Sandfly while abreast of the volcano, are: Latitude, 20° 21' S.; longitude, 175° 23' W.
Since writing the above account, Captain Lane, of the Maile, who visited the volcano thirty-two hours after we left it, states that in his opinion the volcanic action is dying out, that the upheavals are becoming in a marked manner less in height, that the largest he saw was only about 5,000 feet high, and that the island did not appear much more than a mile in length; but others of his ship's crew give two and a-half to three and a-half
miles as its length. The captain also states that the island is now fully 150 feet high. But yesterday and to-day (October 19th) the volcano, as seen from Nukualofa, is again as active if not more so than ever.
The difficulty of putting on paper anything like a correct idea of this grand sight will be fully admitted by every lover of science, but we trust that this short description will enable some who were not permitted to be with us to form some idea of this magnificent spectacle of our latest volcanic eruption.