No. 3.
Mr. Mantell to the Colonial Secretary.

Sir,—

In compliance with the directions of the Lieutenant-Governor, I do myself the honor to transmit to you, for His Excellency's information, the following notes on that part of the Middle Island traversed by me in my late capacity of Commissioner for the Extinguishment of Native Claims.

I must first, however, remind you that the fulfilment of my official duties so fully occupied my time, that I never had it in my power to diverge from my route to investigate Native accounts, however interesting; yet, though my own observations have been so limited, I hope I may be able to furnish some information which may assist more competent persons in the exploration of the country.

The first part of the purchase which came under my observation was the Grand Plain, extending from Double Corner to the Aitarakihi. As the general features of the coast line of this magnificent district are pretty uniform, I shall speak of it as a whole, describing afterwards what local peculiarities struck me as worthy of mention.

Its geological structure, so far as I had the opportunity of observing, was this;—a loamy clay, of thickness varying from nothing to 10 feet, on a substratum of gravel slightly coherent, and page 224composed principally of pebbles of schist, jasper, and white, yellow, and pink quartz. Besides a gradual rise inland of which I have been informed, the plain also rises gently towards the south; thus, while at Te Taumutu it is 8 feet, at Hakatere it is 30 or 40 feet above the sea level.

Along its junction with the Peninsula, there are occasional isolated sandhills, and further north the Waimakariri, near its mouth, cuts through a bed of finely laminated sand, under which, at a depth of about 10 feet, lies a deposit of wood of various kinds, probably the drift-wood brought down by the river when its mouth was some miles inland of its present position: when the Peninsula was an island, and the plain covered by the forest of which so little now remains. A similar deposit is said to exist near where the Waikirikiri discharges itself into Waihora. The wood from each of the above mentioned places is so little changed as to be used by the Natives for firing.

The Maoris state that at a day and a half's journey inland of Te Taumutu there is coal constantly burning, and that they are in the habit of procuring fire from it when passing.

The rivers of the plain are generally too rapid and shallow for navigation. In an open country like this, however, where a dray can pass even now in almost any direction, they are little required for that purpose; most of them end in a lagoon separated from the sea by the beach; through this barrier some break at intervals, while others discharge themselves only by filtering through the shingle. Waihora and some other lagoons are opened periodically by the Natives; a number of narrow trenches are dug, by which they watch and seize with the hand the eels as they are swept out by the current.

The large rivers have each an extensive delta of denudation, commencing a mile or two inland, gradually widening towards the sea, and intersected by flood channels.

From Rakaia to Wakanui the water from the interior finds its way through the gravel bed, and by undermining it has formed along the sea-board innumerable chasms and gullies, which yearly increase in length: there is no other drainage.

At about ten miles south of Waiteruati, the plain ends in the undulating country of Timaru. The superficial strata are here the same as in the plain, supported by a vesicular volcanic rock, reaching a height of about 15 feet, which, gradually dipping to the south, is lost again in the course of three or four miles. The country then resumes its former aspect, save that instead of one vast continuous tract of level land, we have here small narrow plains among gentle downs. According to Native report, a bed of coal 10 feet in thickness crops out on the bank of a stream inland of Timaru.

Striking across a plain about four miles wide, the north point of the Waitaki Valley, Te Morokura is reached. The river, itself a torrent, with a fresh-channel half a mile in width, cuts through the gravel of the plain, which in its bed is mixed with basaltic and porphyritic pebbles brought down by the stream. On the south side the plain is bounded by the Pukehuri Range, composed of highly inclined strata of slate, covered by a ferruginous conglomerate of rounded quartz pebbles. Beyond this the calcareous country of Waiareka commences, and continues to Kakaunui.

The stone is generally porous and friable, consisting almost entirely of the remains of shells and corallines, and containing cidarites, belemnites, terebratulæ, teeth of sharks, &c.

I had no opportunity of ascertaining the respective positions of this formation, and the volcanic grit of Kakaunui; the latter on the coast reaches a height of about 8 feet, dips to the south at a considerable angle, and contains a great variety of crystalline volcanic products, such as hornblende, augite, garnet, &c. It has also thin veins of limestone at right angles to the strata. This deposit is covered unconformably by the usual diluvial beds of gravel and clay.

A mile south of Kakaunui the tertiary blue clay appears, containing volutes, dentalia, and madrepores, a few traces of fish, and small fragments of wood.

Midway between the Bluff and Moeraki it envelopes septaria in great abundance, and varying from 1 to 5 feet in diameter. Hundreds of these lie upon the beach, having been washed out by the sea, some entire and spherical, others broken and glittering with the brown and golden crystals of carbonate of lime, with which their crevices are lined or filled. In an economical point of view these nodules are valuable, as being the material which, when calcined and ground, is called Roman cement. In one of them I discovered a fragment of bone, rather flattened, about an inch and a half across its longest diameter, and in its cancellar structure, not unlike the bones of the dinornis. A thin layer of sand-stone containing numerous shells in some places covers the blue clay.

At Onekakara, a green gritty marl crops out beneath the blue clay; layers of iron pyrites occur at intervals in it. The water that flows through this bed is highly charged with salts, and of extremely disagreeable flavour; but as there is no other within nearly two miles, the Natives at the kaika use it constantly.

Immediately beyond the Native settlement of Moeraki, a dark porphyritic rock, with broken crystals of felspar, crops out. It is traversed in every direction by veins of quartz and calcedony of various colours, sometimes very beautiful. This continues to the end of the Native Reserve at Waimataitai, when the blue clay again appears, and forms the low cliffs of Katiki Bay. In the bight of this bay we met a repetition of the nodules mentioned above, but there they contain a far larger amount of iron and less lime. The space left by the tide at low water is covered with them, of all sizes, from a few inches to 13 feet in diameter. This place is known by the name of Vulcan's Foundry. I regret that I was unable to leave the inland path from Katiki Bay to examine the coal of Matakaea Point. A blacksmith of Onekakara, who has tried it, says that it is so sulphurous that he was soon obliged to discontinue the use of it.

Before reaching Pleasant River, I again walked for a short distance along the beach, and found the cliffs still composed of blue clay. The inland hills seem to belong to the same age as the Pukehuri range at Waitaki. At Waikouaiti, I found Mount Waitikinihi to belong to the same class. Dykes of columnar trap, the columns perpendicular to the sides of the vein, occur at Island Point, the Yellow Bluff, and Brinn's Point; they traverse strata of highly inclined sandstone.

In the little bight south of Island Point, in front of the Native kaika called Makuku or Waipipipaika, is the exposed part of the so-called turbary deposit, whence bones of the dinornis have been obtained in such numbers and perfection. The bed is about three feet in depth resting on blue clay.

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I cannot remember more of the nature of this bed than that it was of a pale buff colour, distinctly stratified and dipping south about 40 degrees. Mother Robinson's Tooth is a column of it resting on trap. It consists almost entirely of decayed vegetable matter, and is studded on its surface with roots of small trees in their natural position and burned to the very ground. It is light and elastic, and emits a strong disagreeable smell. From the quantity of flax it contains, it appears to have been a swamp.

At Blueskin Bay and Purakaunui, the princely country of Otago begins; at the latter place, boulders of serpentine of various shades are plentifully scattered on the sandhills. These bays afford an interesting example of the gradual filling up of harbours when situated in a curve of the coast exposed to a prevalent wind, and unprovided with any river of sufficient strength to keep open a serviceable channel. Like Otago, each has a dry sandspit running from its western nearly to its eastern head; this so deposited by the great action or the sea and the drainage from the land forms a barrier from behind which the detritus brought down from the mountains is tranquilly deposited, to form a small flat through which the streams will flow to the sea. Blueskin Bay, situated in the very bight, is farthest advanced towards the state to which Parakaunui and others similarly situated are invisibly tending.

In conclusion, I may be expected to offer a few remarks on the capabilities of the country. Of the plain I have already spoken in my letter of the 18th September ultimo. Of the correctness of the favourable opinion which I then expressed I have no reason to doubt. Perhaps there is in the South, even portions with less swampy land. With the exception of belts where the gravel has been bared by denudation, the soil seems excellent, and, where cultivated by the Natives, produces most satisfactory crops.

Wood, though generally distant, is nowhere out of reach; while grass, with frequent groves of "ti," covers the plain in every direction, and offers no obstacle to the plough. As far as Wakanui, grass is the usual growth—fern to any extent being rare.

The whole country from Timaru to Waikouaiti is admirably suited for immediate occupation with stock, the northern part being perhaps the best adapted for sheep.

The following anchorages have been frequented by vessels: Caroline Bay, at Timaru, called by the Natives, Te Upokoaterakaitauweki; Oamaru Point; the Bluff Moeraki, or, more properly, that part of One Kakara called the Tryworks; and Waikouaiti. Boat landing-places are more numerous. The River Umukaha is visited by trading boats from Otago. Waihora, when open, is occasionally entered; but with great difficulty from the force of the stream, which keeps the water fresh three or more miles out at sea.

In all the northern part of my journey I saw no district which was not highly fitted for settlement, and I feel confident that so fine a country will not much longer be allowed to remain in its present desert state.

In illustration of some parts of the above, I do myself the honor to forward a few specimens, of which I enclose a list.