Journey to the Head-waters Of The Rakaia—1866.

I now prepared myself for a longer journey into the Southern Alps selecting the head-waters of the Rakaia for this year's campaign. Starting on March the 2nd, and returning on the 18th of April, all the principal source-branches of that river were examined, and the weather was so fine, that during nearly seven weeks of exploration, there were only two days in which I could not pursue my regular work in the field.

After having crossed the Acheron and ascended the alluvial terraces deposited upon morainic and lacustrine deposits, we arrived at the moraines lying across the eastern end of Lake Coleridge, a true lake basin, of the formation and physical features of which I shall speak in the sequel. The newly made road to Browning's Pass led across these moraines and along the hills on the southern side of Lake Coleridge, where well-defined glacier shelves give evidence that here—about 2000 feet above the present bed of the Rakaia—the whole valley was filled with enormous ice-masses, which terminated only on the Canterbury plains, six miles below the gorge; extending in a semicircle from the eastern base of Mount Hutt to the Malvern Hills. At some spots fifteen of these glacier shelves were visible, one above the other, with a fall of from 10 to 12 degrees towards the east.

Instead of following the new road to the ferry, near Goat Hill, I descended about 450 feet by the dray-road, which leads to the stations of Messrs. Palmer and Neave, on the banks of the Rakaia proper. The Wilberforce, which we had to cross near its junction with the Rakaia, was a little swollen from a previous north-west storm, but page 124being here divided into several branches we forded it easily on horse-back. Having decided to ascend, first, the principal branch of the Rakaia, of which the original name has been preserved, I followed the track leading from Mr. Neave's home station along the base of Mount Algidas to the Mathias branch.

Magnificent weather had set in, and the rivers fell very low, so that the crossing of the Mathias could easily be accomplished, even on foot. Fagus Solandri, the white birch of the settlers, hitherto the prevailing tree, now begins to occur more in groves, and sub-alpine shrubs and trees, belonging principally to the Compositæ, Scrophularineæ, Rubiaceæ, Ericeæ, and Coniferæ, are mixed with that handsome sub-alpine tree, giving to the landscape a park-like appearance, the effect of its fine shape and foliage being heightened by the various tints, from pale greyish green to dark brown, by which it is surrounded. This lower vegetation is succeeded by alpine meadows studded with flowers, over which the rugged weather-beaten rocks, forming gigantic peaks, rise in wild majesty. Before us the grand Arrowsmith range rose every moment more and more conspicuously, forming the background of the valley with its splendid peaks and needles.

Seven miles above the junction of the Mathias the river sets against its northern banks, which are covered with dense vegetation, and rise nearly perpendicularly above the water for a considerable altitude. It was therefore necessary to cross to the other side, and although the river was low, it was not a pleasant task, owing to its rapid fall and the large boulders in its bed. Our road lay now on the southern side across a grassy flat, mostly overgrown with the same dense vegetation met with on the banks of all our river-flats, namely, the spiny Wild- Irishman, and the bayonet-like Spaniard (Aciphylla Lyallii). We crossed some considerable water-courses, mostly from glaciers of second order, which here entered the valley from the Arrowsmith range.

Arrived at the point which projects farthest into the river-bed from that range, a very remarkable view opens before the traveller. The valley, still more than a mile wide, stretches for six miles towards the west, and is entirely covered by alluvial accumulations, often consisting of large blocks, over which the river, frequently divided into several branches, rushes with fury. The aspect of such a valley is bleak and cold in the extreme, for at a few miles distance it is not possible to distinguish the turbid water of the meandering river from page 125its banks, and the whole forms one dark grey mass, ascending towards the head of the valley. There, instead of finding as usual, a large glacier filling the whole valley, I observed a true roche moutonnée, reaching halfway across from the southern side, whilst from the northern and opposite to it, a glacier of considerable dimensions crosses the remaining portion of the valley, abutting apparently against the almost vertical northern side of this rounded hill. But I may observe that west of this roche moutonnée there is another valley, and that between the glacier and the hill a torrent rushes down, washing the southern flanks of the former, and thus prevents it from abutting directly against the hill. High snowy ranges, in fantastic forms, rose above, but owing to their distance and the considerable width of the valley, they did not impress the mind with their truly gigantic dimensions, with which I became subsequently better acquainted.

The course of the river compelled us again to cross to the northern side, and, although I selected the best ford, the boulders were so large, and the rush of the water was so strong, that the horses could with difficulty stand against it. We camped on the evening of the 13th of March about a mile below the junction of the Whitcombe Pass stream, at the edge of the sub-alpine forest, where small grass flats offered feed for the horses, and where at the foot of an avalanche channel, formed last winter, a great quantity of firewood was easily procured without the trouble of cutting it.

On Wednesday, March 14, I started at daybreak, accompanied by one of my men, to ascend Whitcombe Pass. The Pass stream contains a good deal of water where it enters the valley of the Rakaia on a large fan, but loses itself by degrees in the shingle before reaching the main river, so that we crossed it dry-footed, following along the edge of the main river to its right hand bank. From here the remarkable opening through the Southern Alps is clearly defined, with the peak of Mount Whitcombe on its western side, raising its bold snow-covered summit above the lower ranges in front. After a mile we had to cross a torrent descending from a glacier of the second order, hanging on to the mountain side like a gigantic iciele. Here we had the first view of the saddle, apparently situated only a few hundred feet above us, and from this point of observation, appearing to consist of a shingle wall, not more than 100 feet high.

Owing to the aspect of the valley, and to its being accessible to more moisture from the west than other similar ones in the Alps, which are page 126protected by lofty ranges in front, many shrubs and annual and perennial herbaceous plants, already in seed in other localities, were here still in full bloom, and I was able to collect many interesting specimens, of which several proved new to science. After half a mile of slow and tiresome travelling through vegetation so dense, that it often allowed us literally to walk on the top of the branches, we descended again to the river-bed, and an equal distance of climbing over huge boulders brought us to the shingle wall stretching across the valley, and along which the river flows on the eastern side, issuing from the central chain near the summit of the Pass. Even alpine shrubs disappear here, and ascending the saddle, a close grown carpet-like turf is found to cover the hill sides, except where shingle slips or rocks occur. This turf, notwithstanding the lateness of the season, was studded with innumerable flowers, mostly belonging to the orders Ranunculaceæ, Compositæ, and Umbelliferæ. Among them, a magnificent large Ranunculus, with yellow blossoms, was conspicuous; since described by Hooker as R. Godleyanus. A further ascent of about 40 feet over enormous blocks of rocks lying in a narrow channel, formed by two taluses of debris, brought us on to the summit of the Pass. The barometer at one o'clock read 25·94, thermometer 54·2 deg. It was a magnificent day, only a few Cirrocumuli rose in the north, disappearing soon amongst the wooded ranges forming the horizon towards the West Coast.

A considerable sized torrent descends on the western side of the Pass into a shingle valley, it is nearly straight for about eight miles, with occasional grassy flats on its banks. On both sides the mountain chain rose majestically above the valley, mostly covered with snow-fields, from which numerous glaciers descend, their outlets swelling the body of this, the most important of the sources of the Hokitika river. The contrast is very striking between these rugged alpine ranges and the quiet outlines of the West Coast mountains, 4000 to 5000 feet high, heavily timbered to their summits, which bounded the horizon, and through which the river forces its way in a succession of deep gorges. The stupendous mass of Mount Whitcombe rises here so steeply above the Pass, that only very little snow can cling to its sides, making it appear still higher and wilder. The reading of the barometer at that time in Hokitika, as I afterwards ascertained, differed only from that at Christchurch by 0·01 inch, and a double set of observations gave me, as mean result for the summit of the Pass, 4312 feet above the sea level. On skirting the wall of debris on the western page 127side of the Pass, I came, after having descended about 30 feet, to the terminal face of a glacier, of considerable dimensions, descending from the north-eastern flanks of Mount Whitcombe, and filling a deep cauldron-like valley. When examining the other alpine Passes of the Province, I observed that invariably a glacier descended on each side, going in opposite directions; and although on the ranges above some of them, true glaciers lie, which are now several thousand feet above the watershed, the glacier shelves and remains of lateral moraines, with which the surrounding mountain sides are covered, show at once that much larger glaciers existed formerly in those localities. These extensive ice-masses have, without doubt, planed the central range on both slopes in opposite directions, till the ridge has been worn down to its present form. Here, on the Whitcombe Pass, this instructive phenomenon is still visible, as the Sale glacier reaches now across the valley, and if the Martius glacier would only advance a few hundred yards, the moraines of both, and perhaps even the ice-masses would meet on the summit of the Pass, although descending in different directions. Thus we observe how nature, to accomplish gigantic ends, uses very simple, but effectual means. In fact, no more simple method could be devised to grind down part of an inaccessible mountain chain than these ice-ploughs, or perhaps, better styled ice-planes, working in opposite directions, which thus open a passage through an otherwise impassable barrier, and allow commerce and civilization to unite the shores of this rich and beautiful island.

I spent the next day in arranging my collection and notes, and the following being wet, I was only able to continue my researches on the 17th March, when I started on horseback to visit the glacier stretching across the valley. It was a beautiful day, the atmosphere clear and pure after the rain, and the aroma of the white flowering Carmichælia odorata and the splendid Senecio cassinioides was so strong that the whole air was filled by it; the latter was, in many localities, so thickly covered with yellow blossoms that scarcely any leaves could be detected. We were able to ride to within 300 yards of the glacial cave, but then the raging torrent issuing from it set against the rocky banks, so that it was impossible to proceed any further. I therefore ascended the mountain side, formed by ice-worn rocks, and soon stood in front of this remarkable glacier, over which the wild stupendous mountains rose in sublimity and grandeur. I shall leave its description to another portion of my narrative, when giving an account of my page 128ascent of Mein Knob, the remarkable roche moutonnée lying between the two glaciers. The glacier itself is near its terminal face, 150 feet high, entirely covered with debris. Its principal outlet flows from an ice cavern close to the mountain side. Large stones were continually falling down from the summit of the ice into the foaming waters below.

My next object being to try if I could not pass along the southern base of the glacier, we led our horses along the present bed of the river, consisting often of very large blocks of rock, in search of a ford, but had to return nearly a mile before I could find a spot where the horses were able to plunge through the swift and muddy water rushing over the large rocks, which offered very bad footing. Arrived at the southern terminal face of the glacier, I observed here also several minor streams issuing from below the ice, which rose in a nearly perpendicular wall, washed by another glacier torrent of considerable size. This latter was confined, on the other side, by the rocky walls of Mein Knob, forming a narrow gorge. I tried in vain to pass along, but, partly owing to the slippery nature of the ice against which the turbulent waters were flowing, partly to the huge blocks of rock falling from the top of the glacier, and the almost continuous shower of smaller debris, I had to give up the attempt to reach the upper part of the valley by skirting this, which I have named the Ramsay glacier. Two barometric observations taken at its terminal face give its altitude, above the sea level, 3354 feet. This glacier is, therefore, next to those at the head of the Pukaki system, the lowest on the eastern side of the central range of this Province.

The magnificent weather continued to favour us, and when I started next day, March the 18th, to reach, if possible, the upper part of the valley by ascending and crossing Mein Knob, no cloud was visible on the deep azure sky, and the atmosphere was so clear that every detail on the slopes of the snow covered giants around was distinctly visible. Pording the river not without some trouble, we reached the foot of Mein's Knob, on the opposite side of the valley and ascended its northern slopes, opposite the terminal face of the Ramsay glacier, and which consist in their lower portion of a great talus of loose debris, near the summit of steep, rocky cliffs, over which we climbed. Approaching the summit, the rocks disappear under a densely grown grass-like carpet of alpine vegetation, studded with flowers, but in many places of a very treacherous nature. The approaches to the page 129summit are formed by gigantic blocks, with the interstices between them grown over, so that when walking, the foot often breaks through the covering of plants. The summit is about half a mile broad, and covered by a succession of bosses, amongst which, at different elevations, lie several small lagoons. The view from here is magnificent in the extreme, and can fairly rival that in any part of our Southern Alps. To the west a large valley opens, about three quarters of a mile broad, in which a glacier of considerable dimensions is situated. This glacier, which I named the Lyell glacier, reaching nearly to the western base of the hill on which I was standing, is entirely covered in its lower portion with debris, but higher up it shows its structure in many seracs, exhibiting peculiar green and bluish hues. Round the glacier rose peak upon peak, sending down their ice streams. Amongst them the rocky pyramid of Mount Tyndall was conspicuous, enveloped in vast snow-fields.

Although the view towards west was so magnificent, that towards north could equally claim my admiration. A high dome-shaped mountain, covered with snow and ice, which I named Mount Kinkel, lies between the two glaciers, separated from my station by a deep gorge, in which the outlet of the Lyell rushes down against the Ramsay glacier. Another majestic mountain range lies between Mount Kinkel and Mount Whitcombe, which I named Mount Ramsay. It is impossible to convey in words an adequate idea of the rugged character of this mountain and its eastern neighbour Mount Whitcombe; turrets, pinnacles, and minarets rise all along the serrated edges, and the rocky face is, in most instances, so steep that no snow can lie upon it. Mount Whitcombe, which when seen from the Pass, appears like a rocky pyramid, extends considerably in breadth, its outlines rugged in the extreme, can scarcely be surpassed by any other mountain. For several hours I was occupied taking the necessary bearings, and making a sketch of the glorious scenery before me, a copy of which was added with some others to my Report on that journey, published by the Provincial Government^* and from which I am quoting largely. It was only towards evening that I reluctantly turned away from this panorama, which for diversity of scenery and its wild alpine character, is second to none in New Zealand.

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On Tuesday, March the 20th, we retraced our steps, and at noon on the following day camped on the right hand bank of the Mathias, near its junction. When rounding the spur of the Arrowsmith range, the contrast, looking east and west, is very striking between the rugged character of the Alps, and the singularly-rounded outlines of the eastern ranges. In the foreground and centre of the valley stands the characteristic Double Hill; above it appear the sugarloaf-shaped hills which surround Lake Coleridge, and over all, the long flat Thirteen-mile bush range bounds the horizon. Having observed shortly before, at the Francis Joseph glacier, on the western side of our Alps, how ice perceptibly rounds and moulds the rocks in its way, not much imagination was required to fill again the whole valley with a sea of ice, planing and furrowing those hills on a more gigantic scale. I may here observe that 1500 feet above Mein Knob, which, according to my calculation, lies 4437 feet above the sea, or 1083 feet above the terminal face of the Ramsay glacier, numerous glacier shelves and lateral moraines occur on the southern side of the mountain, which slope down so regularly towards the east that I could take their angle; which I found to be about 4 degrees on an average. Thus it appears that the valley was here filled with ice at an altitude of nearly 6000 feet above the sea, and yet this was certainly not during the greatest extension of the post-pliocene glaciers, judging from other phenomena observed everywhere in still higher regions.

I started on Thursday, March 22nd, to examine the sources of the Mathias, the most important tributary of the Rakaia above the junction of the Wilberforce. Six miles from the junction of the Mathias with the main river its hitherto broad shingle-bed narrows considerably, and a moraine, 40 feet high, crosses the valley, through which the river has broken a passage, exposing on the eastern side, its peculiar structure. Thus the same phenomenon which I had observed during previous explorations in some of the smaller tributaries of the Waitaki and Rangitata occurs also here, pointing either to a temporary halt of the retreating glaciers or to an advance of the present ones since the Great ice period. The natural features of the country under consideration would, in many instances, at least point towards the adoption of the latter hypothesis. Behind this moraine the valley widens again considerably, as in other rivers under similar conditions, and is filled with a large shingle flat from side to side. Fagus forest, which hitherto had prevailed on the lower side of the valley, ceases here, where the river-bed attains an altitude of 2400 feet, and dense sub-alpine vege-page 131tation, with its various tinted foliage, clothes the mountain side. For two miles more we kept along the eastern side of the valley, travelling mostly on the slopes of huge shingle-fans, and camped under the shelter of a dense group of Phyllocladus alpinus and Dracophyllum longifolium, the north-west winds blowing down the valley with great fury.

Next morning we started with the dawn, hoping to reach, if possible, the head of the valley. Four miles from our camp the valley assumes all the characteristics of a gorge, in which the river leaps incessantly over huge blocks. After another mile of perpetual climbing over such boulders and along taluses of debris, the valley received an important addition from the west, containing nearly as much water as the main river above. This torrent, which we had to cross near its junction, flows in a deep narrow gorge, having the appearance of a deep cleft, which has rent the chain from top to bottom. The higher we ascended, the more the valley narrowed and assumed a rugged appearance; at the same time, the vegetation became strictly alpine, and many of the plants were still in full bloom, filling the air with a delicious fragrance. A mile below the glacier a large avalanche lay across the river-bed, forming a snow bridge from side to side, through which the water had formed a tunnel. Two very prominent peaks rose conspicuously above us, of which the south-westerly one, Mount Tancred, sends a glacier down to the valley; its terminal face I ascertained to be 3788 feet above the sea. Another majestic peak, Mount Carus, lies in a north-easterly direction behind the former, but owing to the great steepness of its sides the snowfields on it are of much smaller dimensions. Another glacier descends from the ridge connecting the two peaks in a deep gorge, and terminates a quarter of a mile above the glacier previously described. Returning on the 24th of March to the junction of the Mathias, I devoted two days to the examination of the slopes of the Mount Rolleston and Mount Algidas ranges, and in preserving and putting in order my collections. I arrived on the 27th March at Groat Hill accommodation house, where I had my horses shod, and deposited the collections, which had already augmented so considerably that they formed quite a load for one horse.

We started on Wednesday, the 28th of March, up the Wilberforce, and kept along the western base of Groat Hill, on the large alluvial deposits brought down by the Boulder stream and Kakapo creek. Before reaching the junction of the Kakapo I observed the remains of a large moraine, crossing the valley and cropping out page 132of the lower portion of the shingle-fan of that creek. Having crossed these morainic accumulations, the present shingle-bed of the river widens considerably, and the road leads over grassy flats to the bed of Moa creek, the most important tributary below the Cascade range. Magnificent Fagus forest clothes the lower sides of the mountains which, in the Cascade range, rise to a great height and are exceedingly ice-worn, whilst numerous water-falls, from whence the range derives its name, appear like so many silver ribbons on the bare rocks, and give a great charm to this part of the road. We camped on a large flat on the northern banks of the Stewart, enclosed on both sides by the shingle brought down by two tributaries, with some lower ground at the base of the mountains, where a chain of deep lagoons is situated. For nearly two miles the valley is more than a mile broad, and in this distance it is joined by three important branches, all coming from true glaciers of the central chain.

I started on the morning of Thursday, March the 29th, to follow the main branch. One mile above the junction of the western branch the valley turns towards south-west, and the hills on the right hand bank of the stream become remarkably low, and consist of stratified alluvium, as seen in a large slip of 200 feet high, reaching to within 100 feet of the summit of the ridge. Two miles above the turn, the Stewart—the bed of which had narrowed considerably and become exceedingly rough, the turbid waters falling very rapidly over large blocks—has a west and east direction, and another small tributary joins it from the south. A quarter of a mile of laborious walking brought us to a glacier nearly 200 yards broad, descending into two branches from a high dome-shaped mountain, which I named Mount Collet; its terminal face is 3584 feet above the sea. Enormous avalanches had fallen from the ranges on both sides near the terminal face, and covered it for a considerable distance with its masses, so as almost entirely to conceal the glacier.

The following evening we reached the so-called Greenlaw's hut, situated a mile below the southern foot of Browning's Pass, having followed the stock-road along the western bank of the Wilberforce, which offered fair travelling ground, except at a few spots where it was destroyed at the crossings of alpine torrents by heavy freshets. We started early on the following day to ascend the Pass, as I wished to get another set of observations, and to examine the geological features of the ranges. When I passed here, about the end of the preceding October, on my return from the West Coast, all the ranges were page 133covered with a uniform slieet of snow; and I was therefore doubly interested to see this portion of our Alps in autumn, when they are most free from it. The southern face of the Pass was, with the exception of a large snow-hole in the Gap and a few minor ones in shady spots, entirely free from snow, but large snow-fields appeared on the slopes of the surrounding mountains flanking it. From the southern one, the Twin Peaks, the small Hall glacier descends; the outlet of which, after a few hundred yards rapid descent, precipitates itself over the vertical cliffs in a picturesque fall.

It was a cold morning, and the whole country was still white with hoar frost when we arrived at the foot of the Pass, having followed the bridle-track which leads to the terrace by which the shingle-slip is reached. Here the road ceases, and we ascended the shingle-slip about 600 feet, climbing along the vegetation on its eastern side till we came at last to the zig-zag track cut up the eastern rocky spur, and although steep and staircase-like in some spots, it is nevertheless well laid out, and has proved a great assistance to travellers. About 9.30 a.m., we reached the summit of the Pass by this track, and I looked around me with great interest. How different the view now to what it was the preceding spring, when the whole surface was covered with one deep sheet of snow, hiding nearly all the remarkable physical features of this depression in the central chain. The snow had now entirely disappeared, except a few large patches in deep hollows on the hill-sides; and a picturesque lake lay at our feet, surrounded by hills mostly covered with a deep green alpine turf, thickly studded with flowers. Over them rose majestically the rugged forms of Mount Harman and Twin Peaks with their snow-fields and ice-masses glittering in the morning sun, which had just vanquished and dispersed the fog lying over them. The water of the lake was perfectly clear, and had in general a stony bottom; a few grebes (Podiceps rufipectus), were swimming upon it, and gave life to the otherwise solitary and tranquil scenery.

On the steep slopes leading to the lake a rich and varied flora was growing: early in the morning, flowers and leaves are generally covered with a thin coating of ice, which gives them a strange appearance, but this soon disappears when the sun breaks through the mist; and these plants, some in full bloom, others budding and which look so delicate, then prove their hardy nature by their bright and uninjured appearance. They were principally Compositæ, umbelliferous, and in a minor degree, ranunculaceous plants which constituted this interesting vegetation. Among the first named were those which formed a thick carpet of flowers, page 134of which. Celmisia sessiliflora and Raoulia grandifiora were conspicuous, also Celmisia petiolata and Haastii and some others of this remarkable genus, there were, besides, Senecio Lyallii, with a profusion of flowers, and the magnificent Ranunculus Lyallii, with its enormous orbicular leaves. Of umbelliferous plants the dwarf Ligusticum aromaticum was to be seen growing in a thick green mat, the pigmy flowers almost hidden amongst the leaves; but over all rose conspicuous the large Ligusticum piliferum, remarkable for its deeply cut leaves and its red, grooved stem. Several rare alpine species of Euphrasia, Senecio, Ranunculus, and many others, gave, in some spots, quite a gay appearance to the turf. On the small shingle reaches two of the woolly Haastias are very abundant, together with the gay Ranunculus sericophyllus, then in full flower.

What impressed me most was the fact that, although winter was rapidly approaching, many of them were just making their appearance, principally round the large snow-holes still lying in many places. When I visited Mount Torlesse two years previously, in the beginning of January, most of the alpine plants were already past flowering, at a corresponding altitude (5000 feet), consequently, here they were three months later. Looking for the causes of this remarkable difference, it will be found that one of the principal is the greater mean elevation of the country as compared with the isolated ridge of Mount Torlesse, rising from the Canterbury plains. The proximityof the latter mountain to the East Coast is another point of importance. But these causes would not suffice were it not that the depression in the central chain is a principal point of attraction for the moisture coming from the West Coast, which is there condensed and precipitated. At the same time I was much struck by the fact that the ranges on both sides, although only about 8000 to 9000 feet high, were covered with perpetual snow and glaciers, clearly proving that, owing to the enormous amount of moisture deposited from clouds almost continually passing through this opening, the line of perpetual snow must lie here much lower than in many other portions of our Alps. Even the vegetation close to and on these alpine passes differs, in many respects, from that of other alpine valleys which do not lead to any Pass. Thus, for instance, the large arboraceous Dracoplyllum Traversii (the nene of the Maoris), is only found on the lower passes, or, as here, near its approaches, indicating that a larger amount of moisture is necessary for its luxuriant growth than our Alps usually supply.

Signs of the great glaciation of that part of the country are every-page 135where discovered in descending the down-like hills lying round the lake on the bridle-path to Hokitika; not only are all the rocks smooth and rounded, but erratic blocks and numerous lagoons are also present. I followed the well-selected track across these hills, descending far down the other side, for a geological examination, till I came to the place where I obtained good sections free from snow, during my first journey. When afterwards ascending the eastern slopes of Mount Harman, a large bird of prey passed within a few hundred yards of us; its large size, more pointed wings, and dark colour distinguished it at once from the New Zealand Harrier (Circus Gouldii), so common on our plains, but which I never observed in the alpine regions. Mr A. J. Mathias, my companion during this trip, had never seen it before, although he had lived several years in the upper valley of the Rakaia, and during that time he had closely observed the birds of that region, neither had the late F. L. Fuller, the taxidermist at the time attached to our Museum, who had collected New Zealand birds for several years, and knew well their peculiarities. We observed the same species (Eagle hawk?) once more next morning, when returning to Goat Hill, above the junction of the Stewart with the Wilberforce, when it was pursuing a sparrow hawk, and flying very high above us. In the evening we reached the hut, after having obtained, during the descent, another set of observations at different points.

We returned on April the 1st to Goat Hill, where we arrived late at night, having first ascended during the day the eastern tributary below Sebastopol rock, and opposite the junction of the river Stewart. The next two days were fully occupied with arranging and packing my collections, which had increased considerably, besides washing and mending the clothes, to which our dense and prickly sub-alpine vegetation is a particular enemy, and preparing for a fresh start. We left on the 4th of April, intending to reach the sources of the main branch of the Harper, and followed the wide river-bed along the opening, disclosing here, on the right bank between Mount Gargarus and the low glacialised hills to the west of it, rocks of the same character as those observed previously in the same horizon. They form, in some localities, banks 12 to 15 feet high, covered with, morainic accumulations and fluviatile deposits; in some places where the upper surface is exposed they exhibit striae and rounded forms peculiar to glacialised countries. Before us rose the bleak Craigieburn range, consisting almost entirely from summit to bottom of one continuous mass of debris. In front, and apparently closing up the page 136valley, rise some very interesting conical hills and other roches tnoutohnees, jutting out from the stony slopes of the Craigiebuŕn range. They are mostly covered with a luxuriant vegetation, and some are so perfect in form that they have been mistaken for volcanic cones by the settlers. Advancing towards the junction of the eastern branch of the Harper with the Avoca, which is the principal one, a large opening is visible leading along the western slopes of the Cragieburn range towards the Canterbury plains, filled with a number of huge roches moutonnées. Magnificent Fagus forest covers most of the valley and hill sides of the Avoca above the junction, the river winding considerably between the picturesque ranges. This, combined with the splendid peats on both sides, makes it one of the most beautiful valleys in our Alps. It thus presents us with a great diversity of views, very unlike those of our large alpine valleys, often so straight that, from the junction of the principal branches that portion of the Southern Alps, with its glaciers whence their sources are derived, are well discernible.

We camped twelve miles above the junction of the Harper with the Avoca, at an altitude of 3194 feet above the sea. For the last three miles the river-bed had already become very narrow, and assumed the character of a mountain torrent, flowing over great boulders, so that crossing it was not without difficulties. Here also the beech forest (the so-called white birch of the settlers), is growing luxuriantly along the banks, and for several hundred feet on the mountain sides. In ascending the valley next day, I observed that the Fagus forest grew to about 3800 feet, or 1370 and 1440 feet higher than in the valleys of the Rakaia proper and the Wilberforce respectively. As the aspect is nearly the same, at least as far as the Wilberforce is concerned, it is difficult to account for such a great difference, except that the narrowness of the valley under consideration may act as a funnel, through which the warm air of the East Coast ascends more easily than in the broader valleys. I observed here, growing on the grassy flats along the river, some shrubby Veronicas, as for instance, Veronica lycopodioides and cupressoides, plants which are common in the smaller branches of the Waimakariri and near Porter's Pass, but which I never observed in the other branches of the Rakaia. During the night, rain from the south-west set in, increasing towards morning; the barometer fell rapidly, and all seemed to point to a breaking up of the fine weather, which had hitherto prevailed, Fearing that the river would rise so as to prevent our crossing, I started early to ascend to its sources.

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After half-a-mile, travelling over great blocks or through, dense forest, we reached the junction of a large tributary, joining the main valley, through a magnificent gorge, and flowing west and east. A little further on the forest began to open rapidly, and the fall of the water became much less. An enormous shingle cone reached into the valley, over which we continued our road. Numerous fine water-falls descend from both sides, and the water brought down by them soon disappears in the shingle. The Fagus forest ends here, and bold craggy mountains, covered with perpetual snow, and with small glaciers on their flanks, surround this remarkable valley. True alpine herbaceous plants were growing in small patches between the dry water-courses, but they soon partly disappeared under the snow which commenced to fall instead of rain. The wall of detritus consisted of morainic accumulations, partly covered on its western side by a huge shingle-fan. Some remains of large avalanches were lying on both sides; and climbing over very rough ground we came, at an altitude of 4749 feet, to a small glacier forming the source of the river. Its direction, as far as I could see, was north 20 deg. east, showing that it is situated on the southern slopes of the high mountains, on the opposite side of which lie the southern or main sources of the Waimakariri. The ground was already covered here with several inches of snow, and the temperature of the air fell to 33 deg. Fahr., so that we felt it exceedingly cold, as we were wet through from the continuous rain lower down. We returned in the evening to our camp; the snow continued to fall nearly all night, so that next morning the ground was covered to a depth of about fifteen inches, and the trees seemed to break under their heavy load. The appearance of the country with this white covering reminded me more of a winter landscape in Switzerland than any similar views I have seen in New Zealand, the pointed, well-shaped Faqus trees, now resembling very much the Pinus silvestris of that country.

The barometer rose during the night of Saturday, April 7th, the snow ceased to fall towards morning, and the clouds began to break, so everything promised a fine day. We retraced our steps, and presently the sun re-appeared. After a few miles travelling, the snow began to dimmish rapidly in the valley, so that when we reached the junction of the Harper with the Avoca, it had entirely disappeared. Intending to reach Lake Selfe the same day, we travelled late at night, and were overtaken by a tremendous hail-storm from the south-east, during which we arrived at a hut lying above that picturesque lake. page 138For the next two days continuous north-west winds blew with vehemence. Great waves rose, and had I not seen it myself, I could scarcely have believed that such a surf could break on the shores of such a small lake. Lake Selfe lies with a chain of similar lakes or lagoons, of which the principal ones are called by the inhabitants of that part—the World, the Flesh, and the Devil—in a longitudinal depression running parallel to the course of the Rakaia above the gorge, and to Lake Coleridge.

I devoted a day to the examination of the Mount Ida range, and the small lake lying between the two northern separated hills forming its shores. Following the eastern wooded shore of Lake Selfe for half a mile, and after ascending the steep sides for about 450 feet, another saddle is reached, where morainic accumulations and glacialised rocks show themselves on both sides at every step. Descending this depression on the opposite side for about 70 feet, we reach Lake Ida, a small but very picturesque spot, with a fine growth of beech forest on one side. As we advance along its banks towards the east, we reach a spot about a quarter of a mile from its western end, where two large shingle deltas approach each other from opposite sides so close as almost to cut the lake in two; the intervening space is only about 40 feet wide, and so shallow that in wading across, the water does not reach above the knees, whilst on both sides it is very deep; very little debris is required, therefore, to divide it into two separate lakes. At its eastern side the lake is surrounded by remnants of a moraine, through which its outlet has formed a channel towards the Ryton: it lies 2304 feet above the sea. The solitude is enlivened by a great number of waterfowl, belonging to various genera, and species, of which the Great Crested Grebe (Podiceps cristatus Lin.) is the most worthy of notice. Eels are also very abundant and of large size, judging from the fact that several of the birds which we shot, disappeared before we could reach them, drawn under water by those voracious fishes. On this occasion we had no dog with us, and had to depend on the wind, or a short swim in the cold water, to bring the birds ashore. I would not have believed it possible that eels could thus, in broad daylight deprive us of our booty, had I not been an eye-witness of the fact. I may here mention that in 1860 a large eel was hooked by one of my party from under a log near the sources of the Buller, and when opened, a whole full-grown mountain duck was found in its stomach.

In following the outlets of the World towards Lake Coleridge, and before reaching the valley of the Ryton, we passed on our right, page 139Carriage road Hill, so called from a very interesting shelf sloping towards west, or opposite to the general direction of the great post-pliocene Rakaia glacier. This shelf, rising at an angle of about 9 deg. for several hundred feet, is about 15 feet broad, and as regular as if formed by the hand of man. It would be quite smooth had not some blocks of debris fallen upon it from the summit. There are similar but smaller terraces above and below it, all running in the same direction. At first I thought that perhaps unusually large beds of conglomerate, striking and dipping in this direction, had offered so much resistance to the denuding or disintegrating powers that these shelves had been preserved, but an examination of the strata proved conclusively to the contrary. There is, therefore, only one other explanation of these remarkable roads possible, which were so striking a feature to the first explorers that they named the range after them, namely, that the icemasses descending by the valley, and uniting with those coming by the large Ryton valley, were stopped and compelled to ascend, in order to move on with the larger masses standing at a higher level. That the power of ice has been here unusually great, is well exhibited by the roche moutonnée standing opposite the junction of the valley of the World with that of the Ryton. This hill, named from its perfect form "Round Hill," is a very striking instance of the power of ice to plane down all sinuosities in its way, if only time enough is allowed for it.

Five or six terraces, together about 150 feet high, form both banks of the Ryton, which river brings the most important supply of water to Lake Coleridge. Ascending the terraces on the left bank of this river, we find ourselves on a plateau about 150 feet above the level of the lake, consisting of the former delta of this river and some minor rivulets coming from the Craigieburn range, and through which the latter have afterwards also excavated channels. Following the last of them in a south-easterly direction, we enter again the opening parallel to Lake Coleridge, where Lake Greorgina and a smaller swampy lake are situated, bounded on both sides by glacialised hills. A small shingle-fan of about 10 feet, resembling all the others previously described, forms here also the watershed, the water flowing in opposite directions. It is thus evident that physical causes, recently in operation, have given to these remarkable parallel depressions their peculiar form, and that the action of enormous glaciers, at work in the epoch preceding the present one, the effects of which being little obliterated, can account only for the curious phenomena met with everywhere in page 140this interesting zone. For several days I occupied myself examining the causes which have led to the formation of Lake Coleridge, and its present physical features, subjects full of suggestive instruction to the geologist. Mr. Charles Harper, under whose hospitable roof I met with a hearty reception, not only placed his boat at my disposal, but also accompanied me during two days on the lake, whilst I was examining its banks and taking some soundings in different parts. I devoted Thursday, the 12th April, to an examination of the lake. The strong north-west wind having ceased for a few hours, I was able to obtain some good soundings as far as the peninsula, but when we reached that spot, the wind came down the valley of the Wilberforce and up the lake with such force, that we had to retreat into the Peninsula bay, where numerous aquatic birds offered a good opportunity for increasing our collections. The peninsula, about 100 feet high, consists of well-rounded ice-worn rocks, true roches moutonnées. The former delta of the Ryton abuts against it, and in several localities amongst the rocks, old beaches are met with, the main part of these deposits having been destroyed during the lowering of the waters, when it came within reach of the waves during the strong north-west winds, which blow here very violently for a great portion of the year.

On Saturday, April 14th, I took the boat once more and went as far as the island, two miles north-west of the peninsula. It was one of those perfectly calm days which occur so very seldom in those regions at least at that season. The lake, unruffled by a breath of air resembled a mirror, thus enabling me to land anywhere on the rocky island, which rose boldly from the glassy surface. I shall never forget the beautiful tints of the lake close to the land. The water, clear as crystal, allowed the eye to follow the perpendicular walls of rock for more than a hundred feet down, till the whole formed a deep purple region, through which the rays of the brilliant autumnal sun were unable to penetrate. The island contains an area of about three acres, rising 30 feet above the lake, and forms a ridge parallel to it with a gentle ascent from the north-west, so that we find the only shallow water round it, is on its subaqueous continuation towards the central chain. On the three other sides it falls very abruptly; so much so that at one spot eight feet from the shore, where I sounded, I only touched the bottom with 106 feet of line; whilst two chains further out it took 230 feet to reach it. Notwithstanding that the rocks are much water-worn, they show still in many spots striæ and flutings from the action of the glaciers. The island in fact is a true page 141roche moutonnée (skör), of which the north-west face, which descends slowly is rounded, worn down, and striated from the almost inconceivable weight of a tremendous glacier, whilst its opposite face is rough and very precipitous. The vegetation on it is very rich and varied. Some enormous beech trees rose majestically over the dense undergrowth of shrubs, consisting mostly of different species of Coprosma, Olearia, Panax, Leptospermum, and many others, generally found on the shores of our alpine lakes, not omitting the beautiful rata (Metrosideros lucida), which grows in large groves, and when in flower, must present a beautiful appearance. I was not a little surprised to meet with the Weka (Ocydromus Australis) on this small island; it doubtless obtains ample nourishment from the berries of the dense growth of shrubs and the insects which frequent them; but it is difficult to conceive how this bird, unable to fly, could reach this solitary spot, nearly a mile from the nearest land.

I devoted another day to an examination of the valley of the Acheron and Lake Lyndon. Following the small valley north of Barker Hill, I reached the former channel of the outlet to the lake, now partly concealed under newer fluviatile deposits. In many localities the remains of moraines, or rounded bosses of rock, stand above these fluviatile beds, by travelling along which I reached the banks of the Acheron, opposite the north-west slopes of the Thirteen-mile-bush range. Descending five or six terraces for about 150 feet I crossed the river-bed and ascended to about an equal height on the opposite side, where I reached the bridle-path leading to the West Coast road, which passes Lake Lyndon. Three miles from this lake the path rises rapidly for about 300 feet on the slopes of a huge lateral moraine, crossing the valley from side to side, through which the principal branch of the Acheron, coming from Big Ben, has forced its way. Numerous angular blocks lie here everywhere on the summit; and several small lagoons without outlet give also to these beds the characteristics, peculiar to those glacier deposits. Behind them, towards Lake Lyndon, the valley opens again and forms a grassy flat, through which, near the moraine, the small creek, coming in the direction of Lake Lyndon, has cut a deep channel, showing in its banks that it is the former bed of a lake filled up with silt. Before reaching Lake Lyndon, we pass a remnant of this former lake, now mostly a large swamp. Behind it the valley still continues of a considerable breadth, and the road leads among tufts of snow-grass along the dry bed of a small water-course till we approach the page 142lake. A shingle-fan, descending from the northern slopes of the Thirteen-mile-bush range crosses the valley here, to the existence of which, combined with that at its opposite end towards the Waimakariri, the lake, without doubt, owes its existence. Its level, when I visited it, was very low, and I found that not only was no water-issuing from it and running towards the Acheron, but that the surface of the water was fully three feet below the point of outlet, and the intervening banks covered with grass.

Thus the Acheron takes water from the lake, except by leakage, only in spring or after heavy rain. My former supposition, therefore, that the large and ever-flowing springs forming the River Porter, and belonging to the Waimakariri system form the real outlet of Lake Lyndon, received additional confirmation. These springs are situated 205 feet below that lake, and at the northern foot of a large fan, formed by several creeks bounding Lake Lyndon to the north. I may here add that I passed Lake Lyndon on the 4th July of the same year. The lake was then so unusually low that it was divided into two distinct basins, of which the southern one was the largest, whilst the northern, or that situated towards the Waimakariri valley, occupied only a very small area. The level of the larger basin was, according to Mr. W. Blake's levels, three inches above the smaller one, although a narrow water-course was continually flowing from the former into the latter. Thus, if there were no subterraneous outlet towards the Waimakariri, it is evident that both basins would stand at the same level. Descending the River Acheron towards its junction, we observe, lying on the western slopes of the doleritic rocks previously described, alluvial beds well stratified, with every appearance of having been deposited in a lake as a lateral delta. In advancing towards its junction with the Rakaia, large beds of silt form high white cliffs, mostly consisting of an almost impalpable mud of a bluish white or yellowish colour, covered by banks of shingle, which show in many places by their flattened shape that they were deposited in a lake. Fighting Hill forms the boundary of this former large lake, and precipitous cliffs, several hundred feet high, situated here at the turn of the river, exhibit well how it was filled up by shingle brought down by the large rivers falling into it, covering and preserving the silt beds, so much more easily destroyed. Moreover, we can trace without difficulty how, after having filled the lake, the Rakaia divided into several branches, running towards the present gorge, and leaving one channel after the other, when they became gorged by masses of shingle

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I returned to Christchurch on Wednesday, April the 18th, after having visited once more the "Curiosity shop" on the Rakaia, to collect fossils. Owing to the indefatigable zeal of my collector, and with the assistance of my party, I brought about 160 skins of birds with me, several of them either new to science or at least very rare, and desirable objects for the completion of our own collection. Besides numerous geological and palæontological specimens, I collected several thousand specimens of dried plants, comprising the nearly entire flora of this portion of our alpine region from the slopes of the eastern ranges to the truly alpine zone near the line of perpetual snow. The observations I was enabled to make of the great glaciation of New Zealand, and of which such remarkable traces have been left with great distinctness on the grand landscape of the Rakaia valley and the Lake region situated in it, will be given in the geological portion of this Report. For several months I was now occupied arranging the collections, writing a report, and preparing maps and sections illustrating the physical geography and geology of the head waters of the Rakaia, which I handed to the Secretary for Public Works on June 20th, 1866, and which, by direction of the Provincial Government, was printed in the same year. For title, see footnote, page 129.