On the Geology of the Province of Wellington.*
[Lecture delivered at the Colonial Museum, Wellington, October 2, 1869.]
The following notes were made during a geological survey of the Province of Wellington, undertaken for the Provincial Government, between 1861 and 1864. The original Reports† are now scarce, and I have been requested to draw up the following abstract of them for re-publication as a preface to the description of the district between Wanganui and Lake Taupo, which formed the subject of my lecture before the Institute.
Since the original publication of my Reports, our knowledge of the geology of the country has largely increased: Hochstetter's work has appeared, the Government Geological Survey has been in progress, and the New Zealand Institute has been established, and in its “Transactions and Proceedings” are numerous reports on the geology of the Colony. Of these new sources of knowledge I cannot take advantage, without entering into discussion, and thereby too much enlarging the limits of this paper; I will therefore confine myself to original observations.
In the classification of the strata I adhere as much as possible to the views adopted by Professor von Hochstetter.
Tabular View of the Strata in the Wellington Province:
Recent. 1. Travertin—found at Te Pura Pura, Hautotara, and other parts on the eastern side of the Wairarapa valley.
2. Raised beaches—extending round the coast.
3. Gravels—Wairarapa plains, Otaki, Manawatu, Rangitikei, Whanganui, etc.
Tertiary. 4. Gravels of high levels.
5. Sandstones and limestones—on east side at Hautotara, Maungarki, and generally skirting the eastern side of the Wairarapa plain. On west side, covering the whole of the great tertiary field.
6. Blue clay—on east side, exposed at Wangaimoana, and very extensively found in the East Coast ranges. On west side, Whanganui and Rangitikei basin, and probably that of Manawatu.
Probable Mesozoic. 7. Limestones and sandstones of the East Coast.
Mesozoic and Paloeozoic. 8. Slates and sandstones of Rimutaka and Tararna ranges, including all the mountainous country between the Wairarapa valley and the west coast at Porirua; and at Cape Palliser, and Kaimanawa range.
Plutonic. 9. Hornblendic rock—found in the upper tributaries of the Pahaua, as boulders: found in situ at Waikekino, not far from Flat Point.
Volcanic. 10. Rocks of Ruapehu and Tongariro, and boulders derived from them, pumice included.
[Footnote] * For the localities mentioned, the reader referred to the Map of the Province, accompanying Mr. Stewart's paper on “the River Systems of Wellington.” See page 198 of this volume.—ED.
[Footnote] † See Provincial Government Gazettes; also, Geol. Map and Sections (Ward and Reeves, 1864).
As it is not intended to give a systematic account of the geology, but rather a detailed narrative of the facts obtained by actual survey, I am compelled to adhere to the natural order in which the observations were made in the course of numerous journeys.
I will therefore divide my journeys into three sections.
1st. To embrace the main range, and its immediate vicinity.
2nd. The Wairarapa and East Coast.
3rd. The Whanganui, Rangitikei, and Manawatu rivers, with Taupo inclusive.
1. Main Range.
By the term main range is to be understood, all the mountainous part of the province which is bounded by the Wairarapa and the Forty-mile Bush on the east, by the flat country of the basins of the Waikanæ, the Otaki, the Manawatu, and the Rangitikei on the west, and by the sea on the south and south-west. This district includes the ranges of Rimutaka, Tararua and Ruahine, with all their spurs and offshoots.
My explorations in the main range were performed in a series of traverses, which it is proposed to describe separately. The first on the list will be:—
Journey from the Hutt, by the Akatarewa River, to Waikanæ, and Thence by Belmont Hill to Wellington.
From the junction of the Mungaroa river, the Hutt takes a large bend to the west. At the extremity of this bend a considerable stream, called the Akatarewa, falls into its right bank from the westward.
Having forded the Hutt, I proceeded up the course of the Akatarewa. Two days journey of pretty constantly wading, brought us near the sources of the river. On the third day we crossed a dividing range about 2000 feet high, and descended upon a branch of the Waikanæ. On the fourth day we reached the village of Waikanæ.
The rocks traversed throughout the journey were of the usual character of those round Wellington—slates and sandstones highly inclined. Some plant impressions were found in the sandstones, similar to those at Porirua. A handsome agate pebble was found in the Hutt river, which, considering also certain igneous boulders which I found in the gorges of the Waiohine and the Ruamahunga, leads me to expect that igneous dykes may be found in the heart of the ranges.
The valley of the Akatarewa contains a considerable quantity of level terrace land, but from the dense nature of the forest, it is difficult to estimate the actual amount.
It is probable that a line of road will eventually be formed by crossing from the valley of the Akatarewa to that of the Otaki, and so connecting the Hutt and the West Coast.
On my return from Waikanæ to Wellington, I took the track from Paoatahanui to the Hutt, apparently passing over a line of strike of soft sandstone and slate rocks, and finding plant beds.
The Hutt Valley, Gorges of Waiohine and Ruamahunga, Forty-Mile Bush, Crossing of Tararua Near Gorge of Manawatu, and Ascent of Tararua by the Otaki Valley.
In February, 1863, I organised a party to endeavour to find gold in the main range. My plan was to examine the different river basins within the ranges, and should gold even in small quantities be found in them, to bottom the plains, or basins lying outside the ranges on both sides.
I looked upon the Hutt valley, however, as almost a decisive test, for it is the great valley of Tararua, and should no gold be found in it, I felt little expectation of finding it elsewhere in these districts. We proceeded to sink a hole in a gully behind Mr. Brown's house, in the Upper Hutt, where some small scales of gold were previously reported to have been found. This hole was sunk through clay and debris, bottoming on hard sandstone, at a depth of eleven feet, without finding the “colour” of gold. In this hole, as in every other which we sunk, we obtained a small quantity of iron sand.
Our next endeavour was to bottom the gravel flats of the Upper Hutt in several places, but from the influx of water we found this to be impracticable; the river evidently percolates through the gravel right across the valley and the quantity of water was quite beyond the power of ordinary pumps. As, however, the bed rock of slate, etc., crops out in many places above this, both in the bed and on the banks of the Hutt, we were enabled to try the gravel where it rests upon the old rocks, but still without success.
We devoted a day to the hills above the Mungaroa swamp without success. We next examined the valley of the Pakuratahi and the gullies in the neighbourhood of Featherston, with similar results.
Passing the Tauherenikau, we proceeded to the Waiohine, which we prospected and washed at every available place for a distance of six or seven miles from the entrance of the gorge. As in the Hutt, it is impossible to bottom the gravel bed of any of these streams below the water level, but there is plenty of bed rock above the water level, with thick beds of drift resting on it. No appearance of gold was found. The rocks were similar to those found on the Rimutaka hill, including large quantities of soft pyritous slates with carbonate of lime veins, and veins of a black mineral, graphite. Boulders of amygdaloidal trap were found here, and also in the stream behind Featherston.
In the upper part of the Wairarapa valley, at the gorge of the Ruamahunga, the formation is gravel large size, resting upon the blue clay, and in the river bed below may be seen the point of junction, where these tertiaries abut on the old and highly inclined rocks. The rise from Masterton is tolerably rapid, and on the Opaki plain, and the adjoining hills, are very palpable marks of the earthquake of 1855 and perhaps of other shocks; at one point there being a lift in the plain of perhaps thirty feet, and a tertiary hill having been split in two, and the western part having slipped down towards the river bed.
In the upper part of the valley of the Ruamahunga river, there is an appearance of a valley of some extent within the hills, but the bush is so dense that I will not venture to guess at the extent of terrace land which may be there. It lies, however, at a height of over 1000 feet above the sea. After rather stiff wading up the river for about six miles, we found the water become so deep from the compression of the bed of the river between perpendicular cliffs, about 150 feet high, that we were obliged to abandon the river bed and take to the forest above. We had by this time, after repeated trials, given up all hopes of finding gold, and were on the look out for a point from whence to ascend the central range; when, after we had proceeded for a mile or two through the bush, the weather suddenly changed, and it soon rained so hard as to force us to a precipitate retreat. My experience of the Ruamahunga was this, that one day's rain raised the river, on the following day it fourth day it began to rain again.
Jaspar and green serpentinous rock are characteristic of the Ruamahunga valley. There is not much appearance of quartz. To a person desirous of reaching the top of the central range, the valley of the Ruamahunga offers the advantage of starting form an elevation of over 900 feet above the sea before
leaving the open plains, and the distance to the open country above the forest is comparatively small.
From the Ruamahunga I proceeded northward through the Forty-mile Bush. Our road descended to the Ruamahunga by the Maori track, crossed the river, ascended a terrace, and then passed over a hill called Kotukutuku, of no great altitude. This hill, however, I believe may be avoided altogether, by taking the line of road lower down on the Ruamahunga. In three hours we reached the Maungawhinau stream, said by our guide, Hemi Paraone to Ua, to be a tributary of the Ruamahunga, but my impression is that he is wrong, and that it runs towards the Manawatu basin. The road frequently crosses this stream, a disadvantage which might probably be easily obviated. After crossing the before described hill, the road was nearly level excepting an occasional ascent of a terrace bank. We encamped on the banks of the Makakahi, on an undoubted northern fall. It is a rapid stream, much encumbered with drift wood.
The weather was very rainy, and it took us two half days travelling through bush and upon terraces and alluvium to reach the Tutækara pa, situated on an open flat on the banks of the Maungatuinoko river. Here we found a population of about one dozen very miserable Maoris, under a chief called Mikara.
The Puketoi range may be estimated as five miles distant to the eastward, and the nearest ranges of Tararua appearing to be about five miles to the west-ward would give a breadth to the valley of about ten miles.
From Tutaekara we proceeded across the plain to the banks of the Maungawha, where that river makes some great bends through cliffs of blue clay and gravel.
The next stream which we crossed is called the Ka-uki, near the junction of the tertiary sandstones and limestones with the vertical rocks of the main range.
The terraces of the Forty-mile Bush are in geological character similar to those of the Wairarapa. The rocks observed are tertiary sandstones, and some limestone, blue clay, and gravels. The rocks of the main range continue of the same character as further south.
Soon after leaving the Kauki we ascended abruptly the main range which here thins out to a comparatively narrow ridge; we crossed it without passing into any valley. The distance from level land to level land on each side does not exceed four or five miles. From the ridge most extensive views can be obtained. The Puketoi range lies opposite—a scarped tertiary formation; over its northern shoulder open country is visible to the eastward. To the southward may be seen the hills beyond Masterton; on the western side the view extends over an immense area of level country. The view from this range gives a strong impression of the ultimate resources of the district. The rocks of the main range here show no change from those further south: the height of the range here is perhaps 2000 feet above the sea.
We descended upon Raukawa; thence we proceeded down the right bank of the River Manawatu, travelling upon a rich alluvium, but observing occasionally the scarp of gravel terraces.
The mouth of the Oroua at Puketotara seems to mark the line of demarcation between the rich land of the interior plains, and the poorer sand tracts towards the coast, and as the aneroid marked exactly the same height at Puketotara as at Te Awahou, I would suggest that the principal township of the Manawatu, ought perhaps to be at, or near Puketotara, and the river navigation improved up to that point, in which case the main trunk line of road from Wellington to the North, would pass through and open fertile lands instead of traversing sand hills.
From the Manawatu we proceeded to ascend the Otaki river.
I was rather surprised at the breadth of fertile land between Otaki and the hills. It took us two hours hard walking (with packs), to reach the Wairarapa pa, and then we had not reached the hills. At the Wairarapa pa the question of the ascent of the river was discussed by the Maoris, and it was settled that a deputation of two was to accompany us to see that we did not carry away too much gold.
The valley of the Otaki river is remarkably similar to those of the Waiohine and Ruamahunga, but it is less wild and the cliffs are not so high. The river winds between cliffs about seventy feet high, composed of highly inclined various thicknesses, from six to thirty feet. Mamaku and other tree ferns abound. The stream is rapid and quite deep enough for wading, indeed it was sometimes difficult to keep one's feet. As we approached the central range the Waitatapia was passed, falling into the right bank. Up this stream lies the road to the Ohau river. A short distance higher up, and we may say at the base of the central range, the Otaki divides into two branches, that from the northward retaining the name of the Otaki, while the southern branch is called the Waiotaueru. The northern branch is said to be full of deep holes and very inaccessible. We ascended the Waiotaueru for some miles, and encamped near where a stream falls into the right bank.
We were now in the midst of soft vertical slate rocks, which had been described to me as full of quartz veins, but the said quartz veins turned out to be carbonate of lime. The same pyritous slates with carbonate of lime veins which I had found in the Wairarapa rivers and elsewhere, were here very largely developed. In the neighbourhood I found the black mineral found elsewhere, viz., graphite, but no metal except iron pyrites is visible in the carbonate of lime veins themselves.
Ascending from Otaki we soon looked down upon the range above Waikanæ, which I find the natives call Rimutaka, so that name is not confined to the range adjoining the southern part of Wairarapa. It now appeared to me that only one ridge separates the Waiotaueru from the Akatarewa, and that by turning to the right in the ascent of the latter river, and crossing one range, the Waiotaueru would be reached with case. After about five hours climbing we found the trees become Alpine in character and covered with moss, and in five and a half hours we emerged from the forest upon the open ridges above at a height of about 4000 feet above the sea. The Alpine trees were mostly totara and black birch. The vegetation above the forest, shrubs of veronica, tarata, a sort of broom, moss, flax, toi and a little grass.
Here we were surrounded by snowy ridges and commanded a most extensive view. The Kaikouras were very distinct, and also the Bluff, and the land about Cape Campbell, with that part of Cook's Straits lying between the latter and the land about Wellington. The mountains surrounding us were broken into long and very steep ridges, separated by ravines some 2000 feet deep, all forest except the line over 4000 feet, which is open, but in which bushes are found, often as difficult to pass through as the bush.
There was no appearance of any level land within the mountains.
We looked down upon the Ohau valley, a deep ravine, but the view towards the far N. W. was shut out.
Karori, Makara, and Terawiti.
The following remarks were made on those districts in December, 1861:—
In November, 1861, I visited the Karori and Waiariki valleys, near Cape Terawiti, and although the men who had been at work at the diggings there were absent, and I was therefore unable to obtain various details, yet I
found an inspection of the valleys highly suggestive as to the direction in which a search for gold should be prosecuted.
There is nothing new in the mineral character of the rocks in the Terawiti district—they seem to consist of a slaty rock, laminated with veins of quartz; of the usual hard green crystalline sandstone, veined with thin threads of quartz, and some hornsoone or chert, and some serpentinous rocks. All the above named rocks are repeated at various points of the Rimutaka and Tararua ranges, and, therefore, if gold be found at one point, the inference is that it may be expected in others. The same rocks, or some of them, may be seen near the Printer's Flat in Makara; at various points on the Karori Road; between Ngahauranga and Pitone; on the Rimutaka Road; and elsewhere.
It is evident that the slate range, which here constitutes the main range of the Island, does contain some gold. Gold is found in it at Terawiti, and in various other quarters, and therefore, after all, it may be an auriferous range—discovery also may soon show that it answers Sir Roderick Murchison's description of gold constants, viz., silurian rocks broken up by granites, porphyries or greenstones, inasmuch as I have found the eruptive rocks in the East Coast country, and I hope before long to find them in the main range itself; added to this we find serpentine in many parts of the range, and although few, if any, well-defined quartz reefs or lodes are found, yet irregular veins of quartz, large and small, are very common. On the other hand the quantities of gold yet found are small.
In considering the geological aspect of the district one enquires where is the most likely place to look for gold in quantity, and one naturally turns to the enormous development of gravel on both sides of the range, and in some of the valleys within it. It is found in small and irregular quantities in the different narrow valleys, including those of Waiariki, and the Karori stream, but denuded in places by the action of the streams. The Upper Hutt and Pakuratahi valleys have their deposits of drift, and probably in the Lower Hutt it will be found below the alluvium of the river; and in the Wairarapa this deposit is of great extent and uncertain depth.
On the shores of the Porirua harbour, between the Peninsula of Tutæ Manu and Duck Creek, I discovered, in 1863, a series of strata, standing nearly vertical, and containing impressions of plants and carbonized substances. It was hoped that the finding of these fossil plants might have led to some scientific results, in establishing the age of the rocks; but the organisms have proved too indistinct and obscure to give any definite information. Taking the line of strike, I looked for, and found, similar organic substances at Oriental Bay, within the limits of the City of Wellington.
2.—Wairarapa and East Coast.
(Summary of Report.)
After returning from the exploration of the valleys of the Akatarewa and the Waikanæ rivers, I again started with the view of gaining an insight into the geology of the N. E. part of the Province, more particularly in the direction of the Puketoe range, and the country generally, lying between the Tararua range and the East Coast.
Leaving the gravel of the Wairarapa behind at Masterton, I found on rising the hills towards the Taueru station, that I had entered upon the tertiary sandstone. This rock I found extending over the whole of the interior of the North-Eastern district, resting upon the blue clay except where some gravel
intervened between the two, but the gravel is by no means largely developed in this district.
This sandstone consists of a series of soft fine-grained sandstones, fossili-ferous, and alternated with fossil beds approaching limestone, and is sometimes of great thickness in this district, seldom less than 500 feet, and in some places I think it must measure 1000 feet.
Some of its fossils are Turritella, Venus, Dentalium, Pecten, Struthiolaria. I have no doubt that it is of the same age and character as the upper sandstone of the Whanganui river.
This formation, where found undisturbed, seems to lie nearly horizontal; but numerous hill sides have slipped into the valleys, there giving the strata the appearance to the casual observer, of dipping in various directions and at high angles.
From the vertical nature of the sections in which this series is found exposed, it has been impossible for me to make any but a partial investigation of its different beds, and the same difficulty is felt in the examination of the cliffs of the Whanganui and other western rivers, —they are so vertical as to be inaccessible.
The blue clay throughout this district does not show much of its thickness above the river levels.
Crossing the Manuka range, the road drops down to the Valley of the Taueru, and thence on to the Taueru station.
Here I visited a very beautiful waterfall, formed by the waters of the Mangarei, a tributary of the Taueru. The stream falls over a ledge of the tertiary sandstone to a depth of about fifty feet, into a large circular pool. Hard fossiliferous beds of this sandstone form the rocks at the fall, the softer overlying beds, which are found in an adjacent cliff, having been denuded.
I may here state that there is a remarkable parallelism between the effects produced in this district and in that of the country inland on the Whanganui and Rangitikei rivers, inclusive. In both districts are the tertiary sandstones largely developed, and in both have these nearly horizontal strata been broken up by denudation, into very rugged surfaces.
Many of the beds of the tertiary sandstone are extremely soft, and therefore liable to be rapidly worn away; some of them, indeed, on being struck by a hammer, instead of breaking into fragments, crumble and run down into pure sand.
Proceeding up the valley of that river, the Forty-mile Bush lay about three or four miles on my left, covering a very broken country.
Ascending the ridge on the eastern side of that river, one looks down on the valley of the Whareama, with its level flats and swamps, while to the northward may be seen the country drained by the Matai kuna, the Oahanga, perhaps also the Akiteo, and here I could see plainly enough that all within view was of tertiary age, the blue ridges of Tararua in the far distance excepted.
Crossing to the Puketoi range, which has an extreme altitude of only 2500 feet, I found the blue clay, and on the ridges above, tertiary sandstone beds, with the usual fossil shells.
Retracing my route to the East Coast, I crossed the Whareama river, passed over a hill and descended upon the Tinui station, situated upon the flats of that stream, a tributary of the Whareama.
Immediately above the station is one of those remarkable hills called “Taipo.” These hills have an extremely fantastic, picturesque, and rugged outling, and at first give the impression of volcanic peaks, but on examination prove to be tertiary sandstones, tilted at an angle of about 70°, and here dipping to the westward; the harder parts of the strata sticking out in peaks, while the softer parts have been worn away.
On the top of the Tinui Taipo I obtained Turritella, Venus, Dentalium, etc. Here also I found that the Matai kona Taipo bore N. 50° E., Buxton's Taipo S. 20° to 30° W., and what I supposed to be Moore's Taipo S. 15° W. It will thus be seen that the several peaks run nearly, but not quite, in a straight line.
Proceeding on the 22nd towards the coast, the road passes for a short distance up the valley of the Tinui, where I found the blue clay. Crossing that stream I ascended a ridge, where a fresh geological series is found, consisting of white limestone and calcareous grits, and in their midst, a fine grained green sandstone.
Descending from the calcareous ridge to the valley of the Whakatake the road follows that stream to the sea, and thence south to Castle Point. We now find a series of thin and soft beds of sandstones and mudstones, cropping out on the beach and in the valleys, sometimes nearly horizontal, and sometimes inclined at high angles. What relation these rocks have to the limestones and calcareous grits, I am at a loss to determine, for I could not here find a section which would throw light upon the subject. My impression is that they overlie the calcareous rocks.
In these sandstones and mudstones I found small seams of coal and numerous impressions of vegetation, but none clear enough to be enabled to judge of their age, but as the coal seams appear to be lignite, or brown coal, we may put them down as of tertiary age.
The reef at Castle Point is a peninsula, forming the shelter to the anchorage. Both it and the rock called the Castle are composed of calcareous sandstone, resting unconformably on the sandstones and mudstones just mentioned. In it I found the usual tertiary fossils. The reef, which is a ridge perhaps fifty feet high, is penetrated by a cave, through which the tide passes, and in which the roar of the wind and waves is very striking. Between the reef and the Castle Rock, the sea has another passage through the rocks into a basin. The Castle Rock is of similar formation to the reef.
In the mudstones and sandstones on the shore I found plant impressions, and in consequence proceeded up the bed of the stream behind Castle Point in the hopes of falling in with some seams of coal. I went on as far as I could penetrate, perhaps three miles, finding plenty of plant impressions, but no actual coal seams.
Mr. Guthrie informs me, that some years ago one of his shepherds, who has since returned to Australia, brought in a handkerchief full of coal (stating that there was plenty more where he found it), which burnt well and seemed of good quality, and which must have been found within three miles of the Castle; but unfortunately he had neglected to ask him where he got it.
My impression is that the mudstones and sandstones of the coast are of tertiary age, and therefore if any workable coal seams are found in them, that the mineral will be of inferior quality.
On the beach here is some iron sand, whence derived it is difficult to say.
Near and Nakaua river I found soft sandstones containing plant impressions and some coal seams about two inches thick. They were not continuous, but thinned out in a yard or two. The rocks are the same as those at Castle Point, and dip slightly to the westward.
Ascending from the beach, in about a mile, I again came upon the calcareous grits and sandstones, both of which prevail in crossing the Trooper, the ridge separating the Whareama from the sea.
From this range the Puketoi is visible, its tertiary character being evident even from this distance.
Descending from the Trooper, I crossed the alluvium of the Whareama valley, and ascended the hill next to Buxton's Taipo, composed of calcareous
grit. The Taipo has a singular family resemblance to that at Tinui, and also dips to the westward.
From Telford's station the calcareous grits continue for about a mile, when the tertiary sandstone and limestone rocks again appeared, and continue all the way to Collins' bush, resting on the blue clay.
In this journey I settled the character of a large block of country, viz,—the whole of the island within this Province lying to the N. E. of the Wairarapa, and between the Tararua and the East Coast. It will of course be desirable to complete a traverse which I propose the make, from the gorge of the Manawatu to the Akitio river and the East Coast, but as I have been through the gorge of the Akitio river and the East Coast, but as I have been through the gorge of the Manawatu, and as I have also been on the Rua Taniwha plains, and at Porongahan, I may very safely venture to predict that in the above named traverse, we shall find nothing but the above described tertiary rocks, with the underlying sandstones and limestones.
I should state that at a distance of about ten miles from the east coast an older series of rocks crop out, and extend to the sea; they are composed of sandstones and limestones. They are often inclined at a high angle, and are doubtless of Mesozoic age.
The streams which flow from the limestone ranges towards the Ruamahunga, deposit travertin in considerable quantities. I observed this particularly at Te Pura Pura and Hautotara. At the former place I found many beautiful impressions of ferns, possibly encrusted only a short time before.
A raised beach may be observed all round the coast except at the foot of the Wairarapa valley, where the sea encroaches on the soft rocks.
Igneous rocks are found in situ in the district. At Waikekino, near Flat Point, I found reefs of diallage on the beach, traversing Mesozoic limestone. In the valley of the Upoko Ngaruru, a tributary of the Pahaou, I found fragments of a similar rock, not actually in situ, but in a position where I think they must have come from a rock in the immediate vicinity.
At Cape Palliser the old rocks appear, and rising to a height of several thousand feet, are lost beneath the tertiaries at about the line of the Pahaou river, with the exception of some small ridges which are found further north—as between Huangaroa and Hildebrand's.
3. The Whanganui, Rangitikei, and Manawatu Rivers, Including a Journey to Taupo.
Having been requested by the Superintendent to examine the rocks of the Whanganui river, and particularly the coal seams of the Tangarakau, a tributary of that stream, and having procured the services of Mr. Samuel Deighton, as Interpreter, and an efficient crew of Maoris, under the command of Topia Turoa, an influential chief, and son of Pehi, the great chief of the Middle Whanganui, I proceeded up the Whanganui in the end of the year 1861, accompanied also by Dr. Tuke and Mr. Walter Jowett.
In consequence of detention by bad weather and holidays, we did not reach Utapu, the residence of the owners of Tangarakau, until six days afterwards. A runanga was then held to deliberate as to whether we should be allowed to proceed to the coal seams or not, and the result arrived at was that we could not be permitted to ascend the Tangarakau.
As the Taranaki war had only finished a short time previously, not by victory on either side but simply by sessation of hostilities, and as many of the Whanganui natives had been engaged in the fight, it was perhaps not to be wondered at that there was some jealousy of the pakeha in the interior.
It was proposed to us that we might proceed as far as the mouth of the Tangarakau, returning on the same day, but as afterwards a demand was made
of a payment of thirty shillings to the kings, for passing beyond our present limits, I declined the alternative, and, in consequence, we returned down stream.
I found the strata entirely tertiary. The surface of the country gave me the idea that it had originally formed a succession of terraces, rising by steps from the coast to the interior, but that the denudation of the soft strata, by the action of running water in the present lines of drainage, had so cut up the former level land, as to make it a very broken country.
There is a general horizontality of the upper strata, at least—the valleys are valleys of denudation; there are no valleys of undulation.
The distance of Utapa from the Whanganui township is estimated at about eighty miles by the river. From the hill above I obtained a bearing of Ruapehu, with a pocket compass, viz., N. 70° to 75° E., (the northern and southern peaks respectively.) This bearing would appear to make the distance in a straight line, thirty-four miles only.
The gravel in the bed of the Whanganui gives a good idea of the rocks which are to be found at its sources. I found the gravel to be principally composed of igneous rocks, viz., traps, tuffs, basalt, etc., but with a proportion, say one-tenth, of hard sandstone and indurated slate rocks, similar to the usual rocks of the main range. As we proceed from Wellington to the N. W., we find in the Manawatu gravel, no igneous rock—in the Rangitikei, a small proportion—in the Wangæhu and Whanganui, the chief part is derived from these rocks.
The slate pebbles in the bed of the Whanganui no doubt indicate slate rock at its sources.
In the ascent of the river we had passed numerous villages and found a large population. Parekino, Atene (Athens), Koroniti (Corinth), Ranana (London), Karatia (Galatia), Pipiriki, Ohinemutu, are some of the names of these villages. They are surrounded by cultivations of fruit trees of maize, potatoes, wheat, tobacco, etc. The vine grows luxuriantly, peaches are in overwhelming abundance, although at the time not quite ripe. At Ohinemutu I found a lemon tree in full bearing, with excellent ripe fruit. Each village had generally an immense church, but, almost invariably, the church was in a ruinous state.
Pipiriki is the capital of the district. It contains a considerable population and a large extent of cultivation. It also possesses some charms of scenery, and is rather more open than other parts of the river. The Whanganui runs in a deep cutting far below the level of the surrounding country. Its immediate banks are generally perpendicular cliffs. On the summit of these cliffs is often a sufficient quantity of level, or of undulating land, on which lie the cultivations of the village. In many places the access to the top of the cliff is by ladders, the villages are entirely hidden from view, which on ascending the ladders are found large and populous. The country beyond rises to a height of perhaps 700 or 800 feet above the river, and is always densely timbered.
At the time of my visit the great lizard superstition was in full force on the Whanganui. A prophet had arisen who had stated that the cause of the disasters of the Maoris was the increase of lizards, that the lizard was the root of evil; that this animal had increased, was increasing, and ought to be exterminated.
In consequence large parties of Maoris were travelling through the country lizard hunting, and at Karatia we found the people cutting down a beautiful grove of karaka trees, to enable them to catch the lizards, that the prophet had informed them were in the trees.
In Hochstetter's section across the North Island, he has put in the Whanganui mountain called Taupiri, as volcanic. We passed near its base,
and I was unable to perceive any appearance of volcanic rocks about or near it. It appeared to me to be simply a scarp of marine tertiaries, possibly, for some reason or another, less denuded than the surrounding land. As Hochstetter was never in the district himself, he must have been misinformed as to the geological character of this hill. On our return we slept at Pipiriki, and on the following day reached the township of Whanganui, distant about fifty miles from Pipiriki.
Ascent of the Rangitikei River.
As I was unwilling to be baffled in the examination of the inland country, I next proceeded from Whanganui to Rangitikei, accompanied by Mr. Samuel Deighton, and having procured a canoe and a crew of four Maoris, commenced the ascent of that river. It was tedious work poling up the Rangitikei, but a canoe journey was the only one likely to give me an opportunity of making out the geology of the district, for the track to the interior is through thick bush, and few sections can be found off the banks of the river.
The geology of the Rangitikei is very similar to that of the Whanganui.
If we generalize the tertiary rocks of the latter river into three series, viz.,—
1. Upper sandstones. 2. Blue clay. 3. Coal shales.
We find in the Rangitikei basin a continuation of the two former. Whether or not the latter lies below, I was unable to determine, for I was never able to find the base of the blue clay, or the rock which lies below it.
In the Lower Rangitikei is a large quantity of gravel, chiefly of the usual sandstone and slate of the main ranges, but with an occasional boulder of igneous rock.
The view from the bed of the Rangitikei, is, if possible, more bounded by vertical cliffs than that of the Whanganui. As the traveller ascends, the cliffs get more vertical, the beds of the streams narrower, and the excavations form what are called in America by the Spanish name cañon*—vertical chasms. In the ascent of the Moawhanga, the stream is so narrow that the trees actually meet overhead. As the sun's rays dart through the gaps in the foliage the effect upon the eye of the navigator below is very remarkable.
The Rangitikei is very inferior in size and in facilities of navigation to the Whanganui. The rapids are far more numerous and the deep reaches few and far between. The chief tributaries fall into its right bank; the largest of these are the Hautapu and the Moawhanga.
The junction of the Hautapu is about half way through the bush.
After six days poling up stream, we left the Rangitikei, and ascended the Moawhanga river.
In some parts of the Upper Rangitikei, I found the river obstructed by bars, composed of very large boulders of hard igneous rocks, apparently not in situ. How they got there requires further investigation. It is quite possible that igneous dykes may be found to traverse the district, but if these boulders have been transported, they must have come from Ruapehu. I looked carefully for any signs of igneous rocks in situ, but could not find them. The marine tertiaries, as far as I could see, occupied the whole district; still, I will not deny, that a further search may discover what the tertiaries rest upon. I wish particularly to call the attention of future explorers to the question of the derivation of these igneous boulders. Broods of whios floundered about around them, some of which we succeeded in transferring to the pot.
The Rangitikei is, for purposes of canoe navigation, very inferior to the Whanganui. The river being smaller, the canoe employed is also smaller.
[Footnote] * ñ is pronounced like gn in French.
The rapids are more numerous, and long deep reaches far less seldom met with. The native population in the higher parts of this river is small in number.
On the sixth day's voyage we left the Rangitikei, and ascended the Moawhanga for half a day's journey, passing through the narrow cañon already described. Our canoe voyage then terminated. We ascended the cliff, and walked to a pa called Pawerawera. Here we found no one at home, but made ourselves comfortable for the night, and on the following day proceeded to Papatahi, where we only found two men and some women and children. The inhabitants of the district had gone to Taupo to celebrate the obsequies of Te Herekiekie. From this point Ruahine appeared about fifteen miles distant to the eastward, with the tertiaries lying on its flank at about the same height at which we stood. I had wished to explore into one of its gorges, but found that my supplies would be insufficient. I was informed, however, that two days' poling in the Rangitikei, above the junction of the Moawhanga, will bring the traveller to the pa Te Awarua, and that probably from that pa as a base the Ruahine might be most easily explored; although a traverse from the Napier country would probably prove the easier operation.
Towards the east, in the direction of Napier, I observed tertiary hills capped with a scarped stratum, evidently limestone. From Papatahi, Ruahine was in sight, bearing N. 55° W., by compass.
We procured a guide and a baggage horse, and started for Taupo. Our route lay through an open and well grassed country; but on both sides there was a large extent of forest in sight. We crossed the Moawhanga by a bridge over a vertical chasm, and slept at Pukehiwi. Leaving the valley of the Moawhanga, we traversed that of the Hautapu, the country improving in pastoral qualities. At Turangerere, on the Hautapu, here is a fine waterfall, and a pa of importance, celebrated for an enormous Waatu or store, built by the late chief Te Herekiekie, and called from its size Niu Tirani. We were still travelling over tertiaries, and at the Moawhanga bridge, at Turangarere, found “Venus,” and other marine shells.
Encamped for the night at a pretty place called Poutamurengi, we bade farewell next day to the valley of the Hautapu, and crossing the Waitangi, passed from marine tertiary rocks to the volcanic products of Ruapehu. The ascent, although no very perceptible, was now rapid. We entered the valley of the Wangæhu, and gradually ascended it to its source. During this day I had observed the range of Kaimanawa, as we passed its southern end, rising out of the tertiaries. At a glance I saw it was a range of old slate rocks. On the rest of our way to Taupo it was on our right, a few miles distant. It is a powerful range, rising to an elevation of over 5000 feet. It is not a continuation of Ruahine, but lies to the westward of the line of that range, and is the highest part in structure of the North Island. Ruapehu was now on our left. On its eastern flank lies a small glacier, or a nevé. Our guide, Tuakau, pointed out to us the marks of the avalanche which fell from this, and ultimately destroyed the bridge of the Wangæhu. The avalanche, after descending the mountain, was carried by its impetus for some miles across the plain, into the bed of the Wangæhu. The left bank of that river, being the highest, stopped the further progress of the avalanche, which consequently formed a dam. The river ran dry below, and formed a lake above, until the accumulated waters carried the debacle before them to the sea, sweeping away the Wangæhu bridge, some forty or fifty miles below.
We could perceive distinctly the marks of the progress of the avalanche across the plain. The ground had been bared, and large patches of bushes swept away.
As all the rivers from the Whanganui to the Rangitikei, both inclusive,
flow in chasms, which may be blocked up at any time by an avalanche, by a fall of the cliffs, caused by an earthquake (as happened in the Rangitikei in the year 1855), or by other causes; an accumulation of water may be collected in the bed of any of these rivers, which, when it bursts, would be dangerous to any bridge not constructed with a clear waterway.*
Abreast of Ruapehu we passed the stone on one side of which the Wangæhu rises, flowing with bitter sulphureous water to the south. On the other side the Waikato flows clear and bright towards Lake Taupo, but before proceeding far it receives affluents whose waters resemble those of the Wangæhu. The watershed of these rivers is the highest point on the road. As we descended, vegetation improved in luxuriance, although all along the bases of Ruapehu and Tongariro, the plants are alpine in character. Kahikatea and black birch, full grown, but only a few feet in height, are common. The mountain torrents are frequent and very beautiful, but their height and rapidity during winter, and the depth of snow which is said to lie upon these plains, may prove a great obstacle to a permanent road through this high country, which shall be open throughout the year. We encamped on the banks of one of these torrents called Waihohonu, I think the prettiest of them all.
On the following day we reached Roto Aira, a lake of considerable size, lying under the northern slope of Tongariro, between it and Pihanga, an old volcanic cone. At Roto Aira we found a considerable village. The inhabitants were very civil, and after cooking food, supplied us with horses to ride to Tokanu, a village situated on the delta of the Waikato, here called the Tongariro, at the south end of Lake Taupo, which we reached in the evening. The river flowing from Roto Aira falls into the same delta.
The group of volcanic mountains which we had just passed, is of magnificent proportions, and if easily accessible, would attract many visitors. Ruapehu is undoubtedly the most ancient cone, and is also the most elevated land in the North Island, attaining a height of upwards of 9000 feet. Doubtless its volcanic forces have long been extinct. It appeared to me to be composed of the harder volcanic products.
Tongariro lies to the north of Ruapehu, and is a mountain of great size, but very inferior in elevation to Ruapehu. No visible signs of volcanic action now appear from the interior of its crater, but the grand active cone of eruption, called Ngauruhoe, 6200 feet high, is a lateral cone of this mountain, rising on its southern slope.†
My impression of Tongariro is, that when at its full elevation it must have been a volcanic cone of very great magnitude, considerably exceeding Ruapehu in height, but that the cone has fallen in, and the mountain is in consequence truncated.
Ngauruhoe is a regular cone of very graceful form, and reaches a height of over 6000 feet. According to the natives, its last grand eruption occurred about twenty-five years ago, when it threw out large quantities of stones; its top, they say, then fell in, and spoilt its beauty.
It always seems to send out volumes of smoke, and is said frequently to emit showers of fine ashes, which disagreeably affect the eyes. Rumbling sounds and discharges, as of cannon, are said to proceed from it.
It is a remarkable fact, however, that very few natives live in sight of the mountain, and sufficiently near to give a good account of its phenomena. From the village at Roto Aira, the cone of Ngauruhoe is invisible, and the
[Footnote] * The character of these narrow chasms is shown in Plate 13.
[Footnote] † Since my visit, Dr. Hector has ascended Tongariro, and has found, and drawn, a lake lying in the bottom of its crater.
natives at the south end of Lake Taupo are shut out from a view of this mountain by intervening hills; while those living further north are too remote for correct observation. Consequently many phenomena may occur which are not observed. On the north-west flank of Tongariro, outside the crater, there is a large puia or hot spring, said to be a specific for certain diseases.
At Tokanu there is a very large area penetrated by hot springs, both in the delta, and on the surrounding hills; more particularly at Terapa, where the late chief Te Heu Heu was smothered by the hill side slipping down and overwhelming his pa in a torrent of mud. When I had seen the line of hot springs extending up the side of the hill whence the mass had fallen, I saw no difficulty in accounting for the catastrophe.
The hot springs, of course, decompose and soften the rocks, and afterwards, by the soaking of rain, slips are brought down.
At Tokanu I found gravel of slates and of quartz, probably derived from Kaimanawa. The hot springs here are very interesting.
The obsequies of Te Herekiekie were proceeding, and many hundreds of Maoris were present. The tangi and other ceremonies were going on all day. The weather was rainy, and what with a damp muggy atmosphere, and the steam of the hot springs, the climate was most relaxing.
I was anxious to visit Kaimanawa, but the Maoris showed so much passive resistance in the way of delays, that I was obliged at last to give up the idea. They were in an excited state, and although perfectly civil, they watched every movement we made.
From Tokanu we procured guides to the Upper Whanganui. Proceeding by canoe to Pukawa, we passed the lovely falls of Waihi. At Pukawa I met the late Iwikau te Heu Heu, and called on the Rev. Mr. Grace, the missionary of the district. In his house I “assisted” at a dinner in the collegiate style, called “commons,” where all the scholars and every member of the household are seated at the same board. Pumice was largely employed in the construction of Mr. Grace's house, and he strongly recommended it as a building material.
From Pukawa we proceeded over an open pumice country, with very fine grass, on which we observed a flock of sheep belonging to the Maoris, as also a few cattle. After passing for some distance to the westward, we opened out splendid views of the volcanic group. The open plains are called the Rua Mata. At the entrance of the Whanganui bush we were obliged to find shelter from a furious thunderstorm, and to remain for the night. Here I was enabled to get good outline sketches of the volcanic group.
Entering the Whanganui bush on the following morning, we had a hard day's journey before we struck the Whanganui river, at a place called Terena. During the day we crossed a stream called the Waipare, and I found its bed composed of old slates with thin quartz veins. It was a matter of crossing two or three yards in which these slates were visible, but it was a great point to find that a base of slates was here to be found, and to form some idea of the thickness of tertiaries above them. As far as I could judge of a country covered by dense bush, I supposed the overlying rocks to be upper tertiary sandstones.
Terena is a pretty spot. We here struck the Whanganui on its right bank, and forded to the opposite shore. Proceeding down stream, we next forded the Whakapapa. In fording the Whanganui and its tributaries, which we had to do frequently, we had to hold on to poles held by all the party. The rivers were rapid and cold, and the stones being slippery, crossing was not unattended with danger.
Camping on the sand bank of the river to avoid the mosquitos, we started on the following morning, and reached the village of Tapuia Kumera, the residence, at that time, of Topini Te Mamako, the principal chief of the Upper
Whangauni. Topini, I found, was an old friend of mine, in the year 1840, in Wellington, so he treated me kindly, notwithstanding his having been a rebel in the Hutt in 1847, and afterwards having fought against us at Whanganui. He was busy getting in his wheat crop, and until that was done we could not get a canoe, so we were obliged to remain patiently. Topini informed me that slate rocks were found two days' journey up the Whakapapa, and he said that they contained a metal—possibly cubes of iron pyrites. This information is probably correct, supported by my discovery of slates in the bed of the Waipare.
At Tapuia Kumera there is a considerable extent of flat land, and since striking the Whanganui we had passed many cultivations. Groves of peach trees were common, and wheat, maize, tobacco, potatoes, etc., were cultivated.
Hereabouts series of strata are largely developed, which, although I discovered no coal seam, I have no hesitation in putting down as coal shales. They dip to the S. W. at an angle of about 20°, and contain plant remains. The terraces, and immediate banks of the river, are chiefly formed of pumice and volcanic ashes, sometimes forming tufa.
I may here call attention to the enormous quantity of pumice which must have been thrown out by the central volcanoes. Terraces of immense extent in the interior, are formed chiefly of pumice, and the rivers flowing from them, such as the Waikato, the Wairoa, the Whanganui, are constantly floating pumice to the sea, on the west, the south-west, and the eastern sides of the island. At the township of Whanganui tons of pumice are constantly floating past, and should the article be of any commercial value a vessel could load at her anchorage in mid-stream, by merely putting out some sort of net to catch the pumice as it floated past.
Two or three miles below Tapuia Kumera, the Ongarue, a tributary of large size, falls into the right bank of the Whanganui, at a place called Taumarunui. Ongarue receives above this junction, the waters of Te ringa motu, and from this point an open country is said to extend, with only one intervening bush, to Ngaruawahia.
At length Topini's harvest was garnered and secured, and we commenced the descent of the river. From Tapuia Kumera to Marai Kowhai, the next village of importance, and the chief residence of Topini, we occupied nine and a half hours transit, giving a distance of probably more than sixty miles.
In this distance we passed the Paparoa rapids, the worst on the river. Above these rapids the coal shales pass beneath tertiary limestones and blue clay, which latter continue far down the river.
Marai Kowhai is situated in the angle on the south side of the Ohura river, where that river joins the Whanganui, falling into the right bank. At this village commenced the warfare with the Ngatitu tribe who were conquered some years ago by Topini.
The Ohura river passes into the Whanganui after descending two waterfalls, in the neighbourhood of which coal seams crop out.
I am informed that this river traverses a fine open country in the direction of the Waipa and the district of Ngatimaniopoto.
On the following day we passed the mouth of the Tangarakau, on our descent, in two hours and three quarters from Marai Kowhai, a distance of about twenty miles. The sources of the Tangarakau must adjoin those of the Waitara.
We find, therefore, three lines of communication opening from the right bank of the Whanganui—
To the Waikato, by the line of Ongarue.
To the Waipa, by the line of the Ohura.
To the Waitara, by the line of Tangarakau.
From Marai Kowhai we reached Pipiriki the same evening, occupying nine hours twenty minutes in the actual transit. As the river was in strong fresh I do not think our rate of speed was less than seven miles an hour, which would, therefore, give a distance between these places of sixty-five miles.
On the following day we reached the township of Whanganui, passing through a district which I have already described.
The results of this journey may be stated as follows:—
That from the flanks of Ruahine a broad sedimentary tertiary belt extends throughout the Province of Wellington, in the direction of Taranaki, bounded inland by the slates of Kaimanawa and the volcanic rocks of Ruapehu.
That coal measures show at three points, viz., at and above Ongarue, at the Ohura, and up the Tangarakau.
That the presence of a base of slate rock is established to the westward of the great volcanic group, viz., in the bed of the Waipare.
The number of waterfalls passed on the banks of the Whanganui is remarkable, and perhaps unique. Below Maria Kowhai I counted 108 which we passed during one hour, and a corresponding number might be counted for two days' journey down stream. Of course some of them are not permanent.
Ascent of the Manawatu.
Leaving Whanganui for the Manawatu, I examined the basin of the Turakina for some milesup, but perceived nothing except the usual tertiary rocks.
Arrived at the Manawatu, I proceeded by land to Puketotara, a native settlement near the junction of the Oroua with the main river. Here I obtained a canoe, and after a tedious voyage against a flooded stream, reached the junction of the Pohangina, which falls into the right bank of the Manawatu, a short distance below the gorge.
The Manawatu country lies low compared with the districts previously explored. There is, however, a blue clay which shows on the banks of the river, and which becomes more exposed on approaching the ranges; this many perhaps represent the blue clay of the Rangtikei and Whanganui, containing cucullæa, etc., but, as I was unable to find the characteristic fossils, I am not prepared to decide this point.
The blue clay is capped by gravel about twenty feet thick.
At the camping place at the Pohangina I obtained venus and pholadomya to 25°, whereas lower down they appear almost horizontal.
From the camping place on the Pohangina we passed through Te Apiti (the gorge). The river has here cut its way through the usual vertical slate and sandstone rocks of the main range. It is a remarkable geographical feature, to find a large river rising on the eastern side of the main range of the island, and breaking its way through, to fall into the sea on the western side.
Passing through the gorge to the Twenty-mile Bush, we emerged upon a level forest country, where I immediately found tertiaries and fossils similar to those I had left on the lower side.
After proceeding for some miles further through banks of gravel, I decided to retrace our steps. In our descent the time occupied in traversing the gorge occupied just one hour. Its length, including windings, cannot therefore exceed six or seven miles.
The Tararua range from the south here meets the Ruahine, both narrowed in width, and of comparatively low elevation.
It will be perceived that in the examination of the basins of the Manawatu, the Rangitikei and the Whanganui, almost the whole of the country is covered by tertiary rocks. This tertiary field appears also to extend over the greater part of the adjoining Province of Taranaki, and passes below the sea level into Cook's Straits.
In the basin of the Whanganui, at the base of these tertiaries, the coal series crops out. I have mentioned three points at which this occurs, viz,—at the Tangarakau, at the Ohura junction, and above the junction of Ongarue.
An inspection of the map will show that these three points lie in a straight line, on a strike of about N. N. E. The dip, where observed, appeared to be to the S. W. I consider that there is little doubt that this formation extends throughout to the westward, to the coal seams of Mokau and the West Coast. It may be faulted, and in places beyond reach, but the probabilities are of its extension throughout this district.
Does this coal field also extend to the eastward, and crossing the Whanganui underlie the tertiary rocks of the Wangæhu, the Turakina, the Rangitikei, and the Manawatu? This is a point of great interest and of great importance, and one which may not be very easy to decide.
The importance of the question will be admitted when it is perceived that a proof in the affirmative would establish the district as the great coal field of New Zealand. I do not speak of the quality of the coal, for that is a point which must be decided after its discovery in different localities, but whether it should prove a coal of very first quality or not, its presence throughout this large area would be of enormous consequence, and would probably add to the advantages of a fertile soil, already enjoyed by the West Coast, the certainty of the future seat of manufactures.
So far as my observations went, this coal question cannot be settled without sinking. Nowhere to the eastward of the Whanganui valley did I find the outcrop of the coal or coal shales; but of course in other localities than those passed, this outcrop may be found, and every exertion should be made to find it.
Is the line of outcrop from the Tangarakan to Ongarue the summit of an anticlinal axis of the coal, or does it show a line of fault? The latter is the more probable supposition. But the main point to be decided is whether the coal series is found at all to the eastward of the Whanganui valley.
On the eastern side of the province I have found small coal seams at various points, and indications of coal in others, and it is possible that workable seams may be found on that coast.
With regard to the probability of gold being found, I have little to add to, or to alter, in the paragraph on that subject in my Essay published in the “Transactions and Proceedings” of last year, and written in January, 1865, except that at Terawiti a small quantity of gold continues to be found, and that a pyritous specimen from the Wai nui o mata has proved slightly auriferous.
Road from the West Coast to the Interior.
I will briefly summarize my reports on this subject by the following observations.
The open country on the West Coast of the Province of Wellington is separated from the open country of the interior by a broad belt of bush. This belt has proved an obstacle of no slight magnitude, both to the settlement of the inland country, and to the rapid concentration of military forces in the neighbourhood of Taupo. A road once opened through this tract would tend very much to the breaking down of the lines of demarcation between the provinces of the North Island, to the mutual advantage of each, politically and com-
mercially Stock might then be driven from Whanganui to Auckland, produce would be raised in the interior, and would find a market on the coast, and settlement and population would spread through the country.
It is true that from Napier the journey to Taupo is comparatively easy; but persons wishing to pass from Whanganui to Taupo will have to make a very long journey if they go by way of Napier.
In the matter of defence, an attack made upon the Napier or Poverty Bay districts, might, with the rapid information conveyed by telegraph, be at once taken in rear from Whanganui, were this road once opened. A force stationed at Taupo might, in a case of danger, be also promptly reinforced from the West Coast.
Whether the line of the Wangæhu, or that of the Rangitikei is the better to adopt, is a matter for the surveyors to determine.