REPORT ON THE CLUTHA COAL FIELDS,

By J. G. Lewis, Esq.

To His Honor Captain Cargill, Superintendent of Otago.

Clutha Coal-field, 21st June 1859.

SIR—Having brought the important task which your Honor was pleased to confide to me to a successful termination, I beg most respectfully to lay before you a report of the operations, showing the nature and quality of the coals, the capability of the mine, and the cost at which it may be delivered on the banks of the Clutha River.

In a former report I expressed an opinion that the site of our operations was part of an extensive coal-field. Upon a closer examination this opinion is corroborated by several facts; the shaft we have sunk being situated nearly on the extreme southern boundary, whilst the original Coal Point, which lies about four miles to the northward, is nearly on the northern one. Between these two points coal is visible on the sea beach at several places, but whether it is an additional bed, or a part severed from the main seam, cannot at present be stated with certainty; but the appearance of the accompanying measures seem to indicate that it is an additional one.

At the northern point greater regularity in the measures prevails, and the coal possesses one decided advantage in having a firm compact roof, formed by the conglomerate sandstone, which is here a continuous rock, whilst at the southern point it lies in immense boulders upon the top of the coal. In other respects there is a great similarity in the seams as to quality and thickness. An opinion generally prevails that the black beds seen at low water, considerably out to sea at the northern point, are beds of coal—this, upon a close examination made at low water, is found not to be the case—they are beds of blaize which form the floor of the coal, the whole of which has been denuded up to the beach.

The shaft is planted, as shown by the accompanying rough sketch and section, upon a high cliff, at a distance of 70 yards from high water mark, and about 15 yards from the boundary line between sections 2 and 3, Coast district. The following is a descending scale of the measures there proved:

No. feet. inches.

1. Turf, Day Earth, and Clay... 18 6
2. Sand of various colours, very loose................. 13 10
3. Quicksand with water....... 3 3
4. Top Coal................... 0 10
5. Black Coal.................. 2 9
6. Upper Splent Coal.......... 3 7
7. Middle Splent Coal......... 3 3
8. Lower Splent Coal.......... 3 6
9. Black Bas.................. 0 6
10. Bottom Coal............... 4 7

The aggregate thickness of clear coal is about 18 feet 6 inches, which is greater than that of any seam in Great Britain with the exception of the Ten Yard Coal of South Staffordshire. The seam dips regularly under the sea to the south-east at an angle of 8½ degrees. It is sometimes bare and visible at low water to a considerable distance, but is generally covered with sand.

The nature and quality of the different beds of the seam are as follows:—

1st, The top coal, No. 4 on the section, 10 inches thick, is a black, rather dirty-looking coal, much mixed with earthy matter, pyrites, and sulphur, and may be considered as of very little value.

2nd, The black coal, No. 5, is a clear, long-grained, black coal, 2 feet 9 inches thick, burns well, and seems suitable for smithy purposes, and would probably make good cokes. Both this and the top coal are of a perishable nature. It was from these two beds, and a very small portion of the upper splent bed, that the parcel furnished for trial to the “Queen” steamer was obtained. This, coupled with the fact of its having been quarried from the sea beach, where it had been washed by the salt water and exposed to the action of the weather, is sufficient to account for the unfavourable report made by the engineer of that steamer.

3rd, The upper, middle, and lower splent coals, Nos. 6, 7, and 8, although occasionally separated by distinct partings, may be considered as one bed. It is scarcely distinguishable from the splent coal of Fifeshire—is of a greyish black lustre and conchoidal fracture. It forms together a fine valuable bed, 10 feet 4 inches thick, burns well, makes a clear cheerful fire, and affords