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Before any fuller account can be given, it will be necessary to have some data from the West Coast, and I propose to go thither as soon as possible, to collect the necessary information.

After my return I shall prepare a more detailed report, together with geological and topographical maps, sections, &c., so as to give a general outline of the structure of this highly interesting country. But in order to give you an idea of the work which has already been accomplished, I refer you to the accompanying maps and sections, of which I shall speak more fully when treating of the formations of which they are intended to give you an insight.*

The western part of the Province of Canterbury consists mainly of a high mountain chain — the Southern Alps — which begins at the saddle of the Hurunui and Taramakau rivers, and continues without interruption to the southern boundary of the Province.

Covered with perpetual snow, from which numerous glaciers descend — twenty-four of which, of the first order I have already visited and observed — this magnificent chain gives rise to all the principal rivers of the Province, which are all true glacial streams.

This main range is the back-bone of the island, stretching through the Nelson Province north of the Hurunui Pass, and thence under different names to Cape Campbell.

This principal chain again commences at Wellington, and continues to the East Cape, attaining its highest elevation in the Ruahine range. This chain consists of sedimentary rocks, sandstones, slates, shales, flagstones, pebble beds, conglomerates, alumschists, &c. These rocks are of very high and as yet undetermined age, no characteristic fossils having as yet been found in them; but from the few fragmentary exuviae of their fauna, and their lithological character, it is evident that they belong to a distant palaeozoic period.

In order to show why no gold bearing rocks have been met with on the eastern side of the Province, I refer you to No. 1 geological sketch map of New Zealand, showing, in broad outline, the different parallel zones.

Gold, as is well-known, is generally confined to metamorphic rocks of silurian age, associated with plutonic and eruptive rocks, granites, syenites, diorites, and hornblende rocks, &c. It will be evident, therefore, even to those unacquainted with geology, that this broad zone of sedimentary rocks of which the Southern Alps are composed, cannot, at least in its northern and middle portions, contain payable gold-fields.

In the south-western part of the Alps, however, in the Moorhouse range as well as along the banks of the rivers forming Lake Ohou, the rocks assume a somewhat metamorphic character, the slates becoming foliated and interstratified with quartz; it is therefore very possible that we may here meet with gold-bearing deposits.

When I was in that district last autumn the season was far advanced, and the snow lying on the ground prevented a search being made. It is my intention, however, in a few weeks to continue my researches in that part of the country, and it is to be hoped that we shall not long remain behind our more fortunate southern neighbours.

I may here add, that gold is generally diffused through many formations, but in such minute quantities that it will not pay the expenses of working.

Therefore, if now and then a few minute specks of the precious metal should be found, we must not hastily come to the conclusion that a gold-field has been discovered.

Several instances have come before me in this Province where a few specks of gold were said to have been found, but on examining carefully the spots where the discoveries were alleged to have been made, I have in no case been able to perceive any traces of it, probably either yellow sand or minute scales of mica having caused the mistake.

The metamorphic and plutonic series, painted pink on the map No. 1, are true gold-bearing rocks, and are confined in our Province to the West Coast, although judging from the richness of the Otago gold-fields the semi-metamorphic rocks seem to vie in richness with those of the more truly metamorphic type in the Nelson Province.

The geological map of the Province, No. 2 of the accompanying series, and of which I am preparing one on a larger scale with all details, will show you that in the Alps, sedimentary rocks of at least two distinct periods occur, although both series agree in lithological character, joints, &c. The relations between these two palaeozoic formations of which the one overlies the other unconformably, are extremely difficult to decipher, and I hesitate to give a decided opinion before I have made some special surveys along the lines of contact. Concerning the formation of the central chain, it is evident that the strata have not only been upheaved, but have also been folded in the most remarkable manner.

The section No. 3, across the island from Banks’ Peninsula over Mount Cook to the westward, will enable you to get a clear insight into the structure of the different mountain chains.

It will show you moreover, how enormous the lateral pressure on both sides has been; on the east side by a large volcanic and eruptive zone, and on the west side by an —

• 1. Geological sketch map of the islands of New Zealand, showing in broad outline the different parallel zones.

2. Geological map of the Province of Canterbury, according to present survey.
3. Geological sections through the middle island of New Zealand, Province of Canterbury, from Banks’ Peninsula to the western slopes of Mount Cook.
4. and 4a. Geological map and section of the Kowai coal measures.
5. Vertical section from north 41 west to south 41 east, Kowai coal measures.
6. Plan of the drive in the Kowai coal measures.
7. Section parallel to the south bank of the River Selwyn, Malvern Hills.
8. Sections along the northern banks of the Hororata, Hawkins Hills.
9. Sections through Canterbury Plains, on the Southern Railway line, from the 29th to the 55th mile, by H. Whitcombe, Esq.