Geological and other Reports
Whanganui, January 1, 1862
Sir,—In accordance with your request that I should examine the rocks of the Whanganui river, and particularly the coal seams of the Tangarakau, having procured the services of Mr. Samuel Deighton, as interpreter, and an efficient crew of Maories, under the command of Topia Turoa, an influential chief, and son of Pehi, and accompanied by two volunteers, Dr. Tuke, whose services were at the command of the sick at our halting places on the river, and Mr. Walter Jowett, who had previously made the ascent, we started up the river on the 21st ult., and I have the honor to report as follows:—
In consequence of detention by Sundays, holidays, and rain, we did not reach Utapu, the residence of the owners of Tangarakau, about eighty miles from this township, until the morning of Saturday, the 28th, and there it was decided that the natives should discuss the question as to whether we should be allowed to proceed farther or not. We had previously remarked, from the commencement of our journey, that there was evidently some disinclination to allow us to proceed, but each tribe or chief seemed to wish to avoid the responsibility of stopping us.
The result of the “korero” was an announcement that Tangarakau was “tapu” to the Maori king, and therefore we could not be allowed to ascend it; but that as we had come so far, if we chose to wait until Monday, the 30th, we might then go up to the mouth of the Tangarakau, accompanied by one of the Utapu tribe, returning downwards on the following day. As it was impossible to proceed without both the consent and assistance of the natives, I was obliged to agree to that arrangement, and accordingly we encamped.
On the afternoon of the following day, Sunday, a rumour reached us that Pehi had sent up a letter, stating his wish that we should not proceed any further, on which I requested Mr. Deighton to ascertain if there was any change in the plans of the natives. After some conversation with them, they informed him that Pehi's letter was of no consequence, and that as they had promised we should be allowed to go to the mouth of the Tangarakau, we should still be permitted to continue our journey so far; but they had discovered that there was a “taiepa” or fence, meaning in our idiom a toll-bar, at Utapu, and that the charge for clearing the turnpike was thirty shillings.
It was represented to them that they had no right to stop a highway open to all; and that any discovery of minerals which might be made could only be for their benefit; that the navigation of the river was in their hands, and that they would see, more plainly than we could tell them, that nothing could be done without their co operation, but having made up their minds they seemed resolved to adhere to their determination.
Considering, therefore, that my objects could not be attained by merely ascending to the mouth of the Tangarakau, that I was tra-page 6velling in an official capacity, and therefore that any acknowledgment of a toll, on my part, would be adopted as a precedent, that having cleared one toll-bar there was no guarantee that we should not find many more as we proceeded, and that no profitable working of any minerals which might exist in that tract of country would be carried on, contrary to the wishes and without the help of the natives, I decided to turn the head of the cauoe down stream on the following morning, in case the natives should still continue obdurate; and as no change in their resolve appeared at that time, we returned towards the township, which we reached on the evening of the 31st ult.
Notwithstanding the present unsatisfactory termination to the expedition, I have strong hopes that the great natural intelligence of the natives will soon show them the desirability of encouraging rather than repressing the development of the wealth of their respective districts; and I have every reason to believe that, on the present occasion, the stoppage of our progress was against the wish of the majority; but, under the highly democratic system of the runanga, which seems here to resolve itself into a public meeting called by any body, which anybody seems in this case to have been a man of no importance, capricious decisions seem to be the natural result.
On the other hand, I have to state that we were received by the Maories with great kindness and hospitality, which, as a general rule, increased the farther we advanced from the settlement, and that their honesty is very remarkable, not an appearance of pilfering of any kind having occurred during the journey. The number of villages and of inhabitants up the river was far beyond what I had anticipated, and the movement and traffic in canoes form scenes both lively and unique.
In consequence of the abrupt termination of the journey, the geological results which I have obtained are few and unimportant. Previous to the ascent of the river I made out the following section on the sea shore, between the pilot station and Kai-iwi.
Tabular view o rocks at Whanganui in a descending series:—
Sand (silicious and iron) in laminæ, sandhills at the top, exposing moa bones near the surface. I should suppose this stratum to be deposited by wind, could I thereby account for waterworn pebbles, mostly of igneous rock; lavas, tuffs, and traps, but also some of grauwacke and quartzite—thickness by estimation 50 to 60 feet.
Ancient forest, with many stumps erect, but most of the trees lying prostrate—5 feet.
A drift gravel of the same composition as in No. 1, say 20 feet thick, but irregular, and also containing fragments of tertiaries.
Soft yellow sandstone, say 60 to 70 feet.
Blue clay which appears to turn into a limestone near the sea level, marine fossils, ostrea, pecten, venus, trochus, terebratula.
N.B.—There is much pumice in some of the upper strata.
In ascending the river I was in hopes that we should find the strata tilted, and the lower beds cropping out, and that we should ascertain whether any secondary or palæozoic rocks lie beneath the tertiaries, and also perhaps discover the altered, or igneous rocks, on which I suppose the tertiaries, or other above named stratified rocks, to rest; but as far as we ascended we found the same series of teria ries, with slight variations, (as for instance, I was unable to trace the ancient forest, No.2, beyond a few miles from Whanganui), as at the settlement, preserving a remarkable horizontality, and consequently exposing nothing which lies beneath.
The surface of the country appears to rise in a succession of terraces, and were it not for the great denudation which has taken place, would probably have represented a series of rising plains; but numerous valleys of denudation have broken up the country into a very irregular surface. Valleys of dislocation have also assisted, of which probably the valley of the Whanganui itself is a grand example. A certain number of faults and slips affect very little the general horizontality of the strata, and consequently there are no valleys of undulation.
The distance of Utapu from the settlement is estimated at about eighty miles by the river, but from a bearing of Ruapehu which I obtained with a pocket compass from the hill above, viz., N. 70 deg. to 75 deg. E., I make the direct distance about thirty-four miles only. Near this I obtained ostrea in the lowest stratum, and at Parakino, twenty-three miles by river from this place, both ostrea and terebratula.
It would still be very desirable, with the consent of the natives, to obtain a survey of the coal seams at Tangarakau; even should it be found impracticable to work the coal so far inland, the dip and strike, nature and age of the seams, might be obtained; and an idea, formed in what direction they are to be looked for nearer to the sea coast, and should the dip prove to be in the direction of Whanganui, and appearances encourage the idea that the coal seams are persistent, and lie conformably (if I may be permitted to apply such a term to inferior strata) under the visible tertiaries, I would then recommend trial bores to be page 7 made at or near the township, which would clearly be the most convenient locality to work any seams which may lie beneath. There can be no doubt of the existence of coal at Tanga-rakau, for it has been seen by many persons, and the Rev. Mr. Taylor has shewn me a specimen which looks very good; but as I have seen so many mistakes made in judging of coal by the eye, I will not venture upon an opinion as to the quality from merely ocular inspection.
I carefully examined the gravel of the Whanganui in hopes of obtaining some information from it. The river itself appears now to bring down no gravel from its sources, the wearing away of the stratified rocks forming sand; but the falling down and wearing away of the bed of the drift gravel (No. 3) has given a proportion of gravel to the bed of the river. This gravel I found composed principally of igneous rocks; traps, lavas, tuffs, and basalt, but with a certain proportion (say a tenth) of crystalline sandstone rocks, traversed by quartz veins, similar to the rock of the main range, and one boulder, and one only, of a slaty rock, with iron pyrites, which seems in New Zealand to indicate gold. These pebbles of altered rock must either have come from the Ruahine, which is improbable, or their original rock must form the bed rock here or hereabouts, and at the time of the deposition of this drift some part of it must have been subject to denudation. I feel convinced that the auriferous rocks, including granite, must cross the Strait from the other island, and lie underneath, but whether they will ever be found accessible, smothered as the country is by tertiaries, is another question. The grauwacke range of the east is found on both sides of the Strait, and the inference is strong that the old rocks of the western range should also be found on the North Island, although perhaps too far down to be discovered.
The report of indications of coal in the immediate neighbourhood of Whanganui can only, according to my present observation, be derived from some part of the ancient forest (No. 2.) The existence of any beds of tertiary or brown coal, beneath the blue clay, can only be proved by sinking or boring.
About two miles above Pipiriki, on the right bank of the river, we found a mineral spring, which, analyzed by Dr. Tuke, proves to be charged with sulphuretted hydrogen.
Linear bands of round stones, some of them like cannon balls, are seen in the river cliffs,—they appear in general to be concretionary sandstone, formed round some body as a nucleus. One which I broke seemed to contain a bivalve shell in the centre. The fish of the old red sandstone, in Morayshire, are frequently found in the heart of nodules.
A few remarks as to the country, although unconnected with my subject, may not come amiss. After fairly entering the hills from the settled districts, one finds the Whanganui river traversing a country of great sameness, but of extreme beauty. A dense and luxuriant vegetation of ferns, shrubs, and trees clothes the hills and cliffs; the valleys are warm and sheltered, and the country, although broken and hilly, can hardly be called mountainous. At a rough caculation the hills do not rise above the level of the river more than from 200 or 300 to 700 or 800 feet, and it appeared to me that were the country held in moderate sized farms, allowing combination of labour to open up narrow roads, it might support a comparatively dense population. Large holdings would be unworkable. The probability of being able to grow wine, or other valuable produce, is considerable. We found at Ohinemutu, a fine lemon tree with excellent ripe fruit, and maize is grown largely. No settlement of the district could be permitted, which did not leave ample room and verge for the natives, but there is an immense extent of country which can never be occupied by them. The general temperature which we experienced, was from 100 deg. to 120deg. Farenheit in the sun; and the winds which we heard of on our return to the settlement we had not experienced up the valley.
It is possible that the natives might be encouraged in other branches of cultivation, as already they begin to grow tobacco; they have introduced ploughs and harrows, and cows are milked daily at almost every settlement. No permanent improvement in the native villages can however be hoped for, while they retain the system of exhausting their land, and then removing to fresh ground; and consequently it would be highly desirable that an improved principle of agriculture should be adopted by them.
To set against the evidences of progress on the part of the Maori race, we found the natives at Karatea (Galatea) cutting down a beautiful grove of karaka trees, to catch, roast, and eat the lizards which are found in their hollows, as they had found that the lizard is the root of all evil!
With regard to the river, its course lies too much to the westward to form the main line of communication with the interior; and I fear that little can be done to improve its upper navigation. Money no doubt could lock it to its source; but whether any locks could withstand the force of floods or chance of earthquakes, is immaterial, for it would hardly pay. Its navigation must therefore remain page 8 in the hands of the Maories, or of men specially trained for the purpose. It may be described as a succession of rapids and long deep reaches, and winds greatly. The flood mark at Pipiriki was about 25 feet above the bed of the river. As the mass of the valleys are valleys of denudation, apparently following the present lines of drainage, it is just possible that a good line for a road into the interior may be found equidistant from and between any two of the rivers running from thence, where an undenuded backbone may have been left.
The difficult part of a road required to connect the open and central plains of Taupo with Whanganui, does not probably exceed thirty miles in a straight line.