ASCENT OF MAUNA LOA. [From Chambers' Edinburgh Journal.]

New Zealand Spectator and Cook's Strait Guardian, Volume II, Issue 112, 26 August 1846, Page 4

ASCENT OF MAUNA LOA. [From Chambers' Edinburgh Journal.]

Of the thousands whom description has rendered familiar with iEtna, Vesuvius, and Hecla, few may have even heard of the equally imposing phenomena that present themselves to the navigator of the Pacific. Among the .fiery cones and simmering craters of Polynesia, those of Hawaii, one of the Sandwich islands, are by far the most gigantic — their elevation being such as to retain a perpetual cap of snow, though situated directly under the tropics. Hawaii, so memorable for the murder ofCaptain Cook, is of an irregular form, fully 260 miles in circumference, and from shoie to shore entirely of volcanic origin. So extremely irregular is its surface, that not a square mile of level ground is to be found ; in fact, it may be said to be one vast mountain, or rather congeries of" mountains, having a common base, and heaving their cones to the height of thirteen, fourteen, and sixteen thousand feet above the level of the sea. The three most remarkable pronvnences are Mauna Kea, Mauna X*oa, and Mauna Hualalai, that of Loa being still in active combustion, and vomiting forth floods of lava from various points of its surface. This mountain is described as a vast dome, sixty miles in diameter, and nearly three miles in height, having a. shoulder or terrace on its eastern slope, in which is situated the active crater of Kilauea, unsurpassed for grandeur and magnitude by any similar phenomena. It is thus that Mauna -Loa has been an object of the greatest interest to navigators ever since the discovery of these islands, and that we have had accounts of the partial or complete ascents by Byion, David Douglas the botanist. Dr. Gardner, and by the recent Exploring Expedition of the United States. In the beginning of 1841, the officers of this expedition pitched their surveying tent on the highest scalp, guaged-and fathomed the craters, cooked their food in the steam fissures — altogether accomplishing a sojourn replete with the most spirited adventure. A brief outline of the commander's narrative cannot fail to interest and inform the the reader. Having procured guides and baggage-men, and being fully equipped for a three weeks' sojourn, the party commenced their ascent on the 10th of December 1840. Having reached Olaa, 1138 feet above the level of the sea, they halted to rest and inspect their forces. From this point, they bad no distinct path to follow, but scrambled over masses of lava. After cansiderable labour, they reached the great plain of the volcano, at an elevation^of 4000 feet, where Mauna Loa burst upon them in all its grandeur. ' The day,' proceeds the narrator, ' was extremely fine, the atmosphere pure and clear, except a few flying clouds, and this immense dome rose before us from a plain some twenty miles in breadth. I had not until then formed any adequate idea of its magnitude and height. The whole dome appeared of a bronze colour, and its uninterrupted smooth outline was relieved against, the deep blue of a tropical sky. Masses of clouds were floating around it, throwing their shadows distinctly on its sides, to which they gave occasional relief and variety. There was a bluish haze resting on the plain, that apparently gave it great distance, though this was partially counteracted by the distinctiveness of the dome. I now, for the first time, felt the magnitude of the task I had undertaken. ' So striking was the mountain, that I was surprised and disappointed when called upon by ray friend Dr. Judd to look at the crater of Kilauea ; for I saw nothing before us but a huge pit, 'black, ill-looking, and totally different from what I had anticipated, There were do jets of fire, no eruptions of heated stones, no cones, nothing but a depression, that, in the midst of the vast plain by which it is surrounded, appeared small and insignificant. At

the further end was what appeared a small cherry-red spot, whence vapour was issuing, aud condensing above into a cloud of silvery brightness. This cloud, however, was more glorious than any I had ever beheld, and the sight of it alone would have repaid the trouble of coming thus far. 'We hurried to the edge of the cavity, in order to get a view of its interior, and as we approached, vapour issuing from numerous cracks showed that we were passing over ground beneath which fire was raging. The rushing of the wind past us was as if it were drawn inwards to support the combustion of some mighty conflagration. "When the edge is reached, the extent of the cavity becomes apparent, and its depth became sensible by comparison with the figures of some of our party who had already descended. The vastness thus made sensible, transfixes the mind with astonishment, and every instant the impression of grandeur and magnitude increases. To give an idea of its capacity, the city of New York might be placed within it, and when at its bottom, would be hardly noticed ; for it is three and a half miles long, two and a half wide, and over a thousand feet deep. A black ledge surrounds it at the depth of six hundred and sixty feet, and thence to the bottom is three hundred and eighty-four feet. The bottom looks, in the daytime, like aheap |of smouldering ruins. The descent to the ledge appears to the sight a short aud easy task, but it takes an hour to accomplish. 'We pitched our tents in full view of the volcano, on its western side, and the natives busied themselves in building temporary huts to shelter them from the cold blast that rushed by. All this was accomplished, and we had time to take another view of the crater before dark. 'A.ll usual ideas of volcanic craters are dissipated uj on seeing this. There is no elevated cone, no igneous matter or rocks ejected beyond the rim. The banks appear as if built of massive blocks, which are in places clothed with ferns, nourished by the issuing vapours. What is wonderful in the day, becomes ten times more so at night. The irrfmense pool of cherry-red liquid lava, in a state of violent ehullition, illuminates the whole expanse, and flows in all directions like waier, while the illuminated cloud hangs over it like a vast canopy. 'We sat on its northern bank for a long time in silence, until one of the party proposed we should endeavour to reach the bank nearest to and over the lake ; and having placed ourselves under the direction of Mr. Dray ton, we followed him along the edge of the western bank ; but although he had been over the ground the day before, he now lost his way, and we found ourselves still on the upper bank, after walking two or three miles. We then resolved to return to the first place that appeared suitable for making a descent, and at last one was found, which, however, proved steep and rugged. In the darkness we got many a fall, and received numerous bruu.es ; but we were too -near the point of our destination to turn back without fully satisfying our curiosity. We finally reached the second ledge, and soon came to the edge of it; we were then directly over the pool or lake of fire, at the distance of about five hundred feet above it ; and the light was so strong, that it enabled me to read the smallest print. This pool is fifteen hundred feet long by one thousand wide, and of an oval figure. ' I was struck with the absence of ,any noise, except a low murmuring like that which is heard from the boiling of a thick liquid. The ebullition was (as is the case where the heat is applied to one side of a vessel) most violent near the northern side. The vapour and steam that were constantly escaping were so rarefied as not to impede the view, and only became visible in the bright cloud above us, which seemed to sink and rise alternately. We occasionally perceived stones, or masses of red-hot matter, ejected to the height of about seventy feet, and falling back into the lake again. , ' The lake was apparently iising, and wanted but a few feet of overflowing its banks. When I began to reflect upon the position we were in, its insecurity, and the vast and deep fires beneath, with the high basaltic walls encompassing us on all sides, the sulphureous fumes and broad glare, throwing such enormous masses of stone in strong relief by their own fusion, I found it difficult to comprehend how such a reservoir can thus be pent up, and be viewed in such close proximity, without accident or danger. The whole party was perfectly silent, and the countenance of each individual expressed the feeling of awe and wonder which I felt in so great a degree myself, and which the scene was so well calculated to excite. 1 Having determined to encamp at Kilauea for a few days, the exploration of the crater I was the next subject that engaged their attention. This was done with great difficulty and no little danger. * The pathway leads down on the north-east side over frightful chasms, sometimes on a mere edge of earth, and on

f rocks rent asunder to the depth of several hundred feet. Through these fissures steam issues, which, as it reaches the upper part, condenses, and gives notrishment to masses of ferns, and an abundance of small bushes (vaccinium), bearing a small berry of an agreeable flavour, called by the natives ohela. The descent, however, is not in reality difficult, except in a few places, where it requires some care in passing over the basaltic blocks, that are here piled in confused heaps. On approaching the black ledge, which from above appeared level and smooth, it is seen to be covered with large pieces of lava, rising in places into cones thirty or forty feet high, which are apparently bound down by huge tortuous masses, which surround them like cables. In other places these are stretched lengthwise on the level ledge, and look like hideous fiery serpents with black vitreous scales, that occasionally give out smoke, and in some cases fire. ' The immense space which I have described the crater as covering, is gradually filled with the fluid mass of lava to a certain point, above which the walls, or the surrounding soil, are no longer able to bear the pressure ; it then finds vent by an eruption, previous to which, however, a large part that is next to the walls of the crater has in a measure become cooled, and remains fixed at the level it hail attained. After the eruption, the central mass therefore alone subsides three or four hundred feet, and leaves the portion that has become solid, forming a kind of terrace or shelf : this is what constitutes the " black ledge," and is one of the most striking features of the crater. Its surface is comparatively level, though somewhat uneven, and is generally coated with a vitreous, and in some places a scoriaceous lava, from half an inch to an inch thick, very iridescent and brittle. In walking over this crust, it crumbles and cracks under the feet: it seems to be easily decomposed, and in some places had lost its lustre, having acquired a grayish colour, and become friable. ' To walk on the black ledge is not always safe, and persons who venture it are compelled for safety to carry a pole, and feel before they tread over the deceitful path, as though they were moving on doubtful ice. The crackling noise made in walking over this crisp surface (like a coating of blue and yellow glass) resembles that made by treading on frozen snow in very cold weather. Here and there are seen dark pits and vaulted caverns, with heated air rushing from them. Large and extended cracks are passed over, the air issuing from which, at a temperature of 180 degrees, is almost stifling. Masses are surmounted that it would seem as if the accumulated weight of a few persons would cause to topple over, and plunge the whole into the fiery pool beneath. *On approaching the large lake at the southern end of the crater, the heat becomes almost too stifling to bear. I shall not soon forget my employment therein, in measuring a base to ascertain -the extent and capacity of the lake, of which some account will be given hereafter. At about two-thirds of the distance from the north end are extensive sulphur banks, from the fissures in which much steam is continually escaping ; in these fissures are seen many beautiful chrystals adhering to their sides ; while on the bank itself, some specimens of sulphate of copper, in beautiful blue chrystals, were found. ' From many places on the black ledge a bluish smoke was seen issuing, smelling strongly of sulphur, and marked by an efflorescence of a white tasteless powder among the cavities : this it was difficult to detach without scalding the fingers. There were many cracks where our sticks were set on fire, and some places in the vaulted chambers beneath where the rock might be seen red-hot. * The black ledge is of various widths, from six hundred to two thousand feet. It extends all around the cavity, but it is seldom possible to pass around that portion of it near the burning lake, not only on account of the stifling fumes, but of the intense heat. In returning from the neighbourhood of the lake to the point where we began the ascent, we were one hour and ten minutes of what we considered hard walking ; and in another hour we reached the top of the bank. This will probably give the best idea of its extent, and the distance to be passed over in the ascent from the black ledge, which was found six huudred and sixty feet below the rim. (To be continued.)