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alluvium above the rock and only an inch or two of soil.

That gold dust might have been thrown into the well is possible; but the specimens sent to Melbourne were collected from the rubbish heap afterwards, and therefore not likely to contain any foreign mineral. I shall endeavour to make a further examination, particularly as more grains of gold are said to have been found in the neighbourhood and as I see some appearance of mineral veins close at hand.

I must now make some small corrections as to Mr. Brough Smyth’s idea of our mountain chains. His view is, naturally enough, that our main ranges throw off spurs East and West, spreading across the country, whereas the remarkable feature is this, that the mountain ranges of the Rimutaka, Tararua, and Ruahine, including all the mountainous country in this neighbourhood, pass like a wall to the N.N.E., the spurs keeping on the whole the same direction as the main ranges. Of course one does not speak of a wall as built by a stone mason, a rigid line, nor do all the spurs and ridges adhere to a strictly N.N.E. course, but such is the main direction. The main strike of the rocks, being I should say about North (magnetic), with however many exceptions.

Most of the maps give an erroneous impression, by marking a range, curving from the Ruahine N.N.W. towards Taupo, which range does not exist, although the broken tertiary plateau may there reach an elevation of 2,000 feet. *

In its broadest part, from the coast opposite Mana to the Wairarapa, the main range does not appear to exceed twenty three miles wide. At the gorge of the Manawatu, the breadth following the curves of the river, is only about seven miles.

These mountains have assumed their form, less from upheaval than from lateral pressure. The strata are accordingly bent and folded upon each other, and the ranges are separated into a succession of sharp and nearly parallel ridges, culminating in height towards one or more central axes, but high and abrupt also at both sides, where the sea, or the tertiary rocks, meet them in a horizontal, or nearly horizontal line.

One consequence of this conformation is that the rivers, while within the ranges, run in ravines, rarely as in the instance of the Hutt, expanding into valleys.

• For a description of the volcanic chain or block of mountains of Ruapehu and Tongariro, see my report of February 17th, 1862.

Anticlinal axis near the centre of direction of the range, we there find, in the central axis, the granite of the Upper Hutt and Mungaroa; but I have strong doubts whether we shall find it on the surface in the high parts of Tararua, although it may be assumed to form the hidden nucleus of that range. The basalts, like the diorite rocks of the Canterbury Province have not yet been found “in situ,” and are not likely to appear in a prominent way; and the only rock which I can venture to call lava, in this main range, is the red rock of the Rimutaka, (on the authority of the Rev. W. B. Clarke,) but where it is found, and elsewhere in these ranges, there are no signs of volcanic vents.

The stratified rocks, sand stones, mudstones, slates &c., seem to, and I think will be found to continue to, occupy the main part of the ranges.

The accumulations of drift on the Eastern side of the ranges are fully equal to those on the West, and the tertiary rocks may be said, with some exceptions, to be of the same character and thickness on both sides of the main range. Mr. Brough Smyth, suggests as particularly worthy of immediate attention, the basins of the Hutt, the Waikanae, the Otaki, the Manawatu, the Rangitikei, and the Whanganui. I would omit the word immediate in reference to the three last named of these rivers and substitute for their names those of the Ruamahunga, and its tributaries on the right bank, the Waipoa, the Wai Ngawa, the Waiohine and the Tauhere Nikau, (perhaps this last cannot be called a tributary.)

Although I should like to see the head waters of the Whanganui prospected, yet, even supposing the natives would consent, the expense of a party would be enormous in proportion to the work done. I only found about two yards of the ancient rocks during a journey of some hundreds of miles in that direction, and then in the bed of the Waipare, a tributary of the Whanganui, with the hills, formed I believe of tertiary rocks, rising at an angle of 45° or thereabouts, on both sides, to a height of say 700 feet above the bed of the stream. I consider that the Upper Whanganui, must wait the progress of development of the gold fields from Coromandel through the Waikato country, which may throw sufficient light upon the subject.

The same remarks will apply to the Rangitikei River, and those rivers lying between it and the Whanganui. The heads of these rivers would answer Mr. Brough Smyth’s idea of searching towards the sources of the streams, but a prospecting party to explore them must be fitted out.