The Pamphlet Collection of Sir Robert Stout: Volume 22
Will play an important part in the future of New Zealand, and the whole of the Southland district will share in the prosperity which must follow the systematic working of our coal measures. A cheap and economic fuel is a necessity in profitably working many industries. The coal measures at the Night-caps are the only mines in Southland that are efficiently worked. In the Government returns for the year 1882 it is shown that 6730 tons was the output for that year. The coal is classed under the head of hydrous, and it is a pitch coal; its structure is compact, has a smooth fracture, does not desie pact on exposure, nor is it absorbent of water, and it burns freely. This mine could probably be wrought very economically if the proprietors were to adopt Messrs Sebastian, Smith, and Moore's system of coal getting by compressed lime. I will explain it. "Cartridges are employed consisting of nearly pure lime, 2½ inches diameter, which, by hydraulic pressure, are reduced from 7 inches to 4½ inches in length, the density being thus nearly doubled; when slaked in an unconfined space, these occupy about fire times their original bulk. The shot holes are drilled by means of a light boring machine. The cartridges are then enclosed by tamping in the same way as powder, and they are slaked by means of a small force-pump. The time occupied in drilling a hole three feet deep is 10 to 30 minutes, according to the hardness of the coal. On the removal of the sprags, which are left in, the coal falls clean from the roof in large masses ready for loading, practically making no small. The following are among the principal advantages claimed for this system. There is no smoke or noxious smell of any kind. The roof is not shaken by this process; no vacuum is created, as is the case with a blown-out shot; and the coals in falling produce much toss dust, thereby reducing the danger which is generally admitted to arise from the air of a mine being heavily charged with small particles of coal. Skilled labour is unnecessary, and the coal can be got with much less exertion to the collier than by wedging. After pumping the water into the charged holes the men need not discontinue working, as is the case with gunpowder, for, simply moving away from the face of the coal while the sprags are being taken out, all risk of injury from falls is avoided." A comparative result of coal-getting by the above system, and by labour at fifty different collieries, was as follows:—Men working 320 hours in the ordinary way of wedging brought out 628 tons. By using the lime patent, men working 219 hours brought out 768 tons.
It is werthy of extensive record that the engines on the Southland section of the New Zealand railways are driven with Nightcaps coal.
But not alone at Nightcaps will the district have wealth brought from the hidden treasures underground, for extensive coal measures await development at Orepuki, which is not a greater distance from Invercargill than the Nightcaps, and in addition to the coal, which appears to be of the same character, class and quality, extensive beds of shale overlie the coal measures. These have been more or less tested, and are found to produce an excellent lubricating off and a food light burning oil, whilst the shale will be without doubt extensively used for gas making purposes, as it will raise the standard of gas for illumination to a high degree of excellence. For some time past the engineer of the Municipal Gasworks has been experimenting with Southland coal, with the object of using it, either solely or partly, with Grey-mouth coal for the production of gas, and he appears confident that it can be economically employed for that purpose; and as the railway will be completed to within a short distance of the coal seam there within the ensuing twelve months, a supply of Orepuki coal will be then available for local consumption. Whilst noting all these favourable points in regard to local coal, I wish to guard myself from being suspected of being interested in any local company, by pointing out that, however good these coals are, for local consumption, we shall not be in a position to export them coastwise, as the price obtainable outside of the district would not be sufficient to enable them to compete with page break Newcastle or West Coast coals, when railway and ship's freight were added. The production and consumption will therefore entirely depend on the requirements of the Southland district. But local coal should effectually, by reason of the price it ought to be sold at, prevent imported coal finding a market, in Southland.