GEOLOGICAL SURVEY OF NEW ZEALAND.

Hawke's Bay Times, Volume 8, Issue 454, 27 December 1866, Page 1

GEOLOGICAL SURVEY OF NEW ZEALAND.

[Hawke's Bay Times, 3rd December.] Returning, according to our expressed intention, to the official report on the coal deposits of New Zealand, we take up the subject at the point at which we then left it > viv., the comparative value of the coal of New Zealand in relation to that of the North of England, Wales, and the Australian Colonies. The samples of New Zealand coal which were submitted to trial against the other kinds were obtained from the Grey and the Buller districts, and is of that kind which we have referred to as anhydrous. Of the Grey coal Dr Haast informs us that it extends over an area estimated at 15 miles by 6 miles in breadth, gradually rising from the sea level at the very moderate angle of from 10° to 30° to an altitute of several thousand feet, thus being most favorably situated for working at the smallest possible cost, requiring neither shafts nor machinery for pumping; that there is no apparent disturbance of the bed at any place, nor any reason to suppose it may not be worked throughout the whole of the area named; that there are at the least four workable seams, the main seam being 15 feet 3 inches in thickness; that it has been used to a great extent by coasting steamers, and has given great satisfaction, and that a sample tried in the Dunedin Gas Works yielded a large quantity of illuminating gas. Of the Buller coal there are reports by Dr Haast, and Messrs Rockford, Burnett, and Blackett, from which is gathered that the outcrops of this coal occur at an altitude of more than 1)500 feet above the sea level, extending northwards (possibly not continuously) for a distance of 80 miles to West Wanganui, where outcrops also occur, but at the sea level; that in the immediate neighborhood of the Buller the existence of workable seams over an area of at least 15 square miles is considered as certain, the seams in aggregate thickness measuring 38 feet, and containg an estimated available quantity of 200,000,000 tons. From the report sent by Mr Trickett (partly quoted in our former article) Mr Burnett constructed four tables, in order to lay before the New Zealand Government a summary of the results obtained. One of these tables is given, which shows the quantity of coal of each kind required to evaporate a given quantity of water, and for comparison the North of England coal is taken as a standard, the following being in brief the result: —

In commenting upon these experiments Mr Burnett makes the following remarks:— The samples of coal, both, from the Grey and Buller, -were taken from within a few feet ortho outcrop, and almost close to the surface, and It la only fair to conclude (as, indeed, the recent working at the Grey has demonstrated) that the quality of the coal will Improve as the works are continued further from tha outcrop, and deeper below the surface. It is to be presumed that the North of England, Welsh, and New South Wales (being from actual working minea,)*wouldbea fair average of the mineral in its full perfection; and in tha case of the two former, pntoably fresh fromthe mines, whereas that from the Grey and Buller was mere outcrop coal, not tested for mors than sit teen months after It was worked, and after being broken and deteriorated by shipping, re-shipping.- carting, packing, and conveying to the other side of the world; so it la only reasonable to conclude that samples of these coals, a moderate depth from the surface (such as wUI be produced when the mines are actually wdrked), tested under equally favorable circumstances, would contrast still better than they do at present. When the Grey and Buller coal was packed in boxes at Nelson, the dead small was taken out and put In bags, bat was not Intended to be sent to England; however, by mistake it was sent, and to this accident wo are indebted far one Of the most valuable results of these trials, vis., that the "oosl in bags” (see second report) I*, the dead small, is very nearly equal to any cither part of the coal This is a most important quality, as it does away with the necessity of screening, by which a considerable percentage of other coal is wasted: the naU at Wekb coal

Another very valuable property is the Email quantity of clinker and ash contained in this coal, and what little clinker there is does not stick to the bars. The amount of disagreeable labor saved by this can only be thoroughly appreciated by the working stoker. Indeed, it appears that no stoking whatever is required, “but that a small increase of the water evaporated per hour is obtained when the fires are stoked.” This is shown very clearly in table No. IV, second part, where, la the trials of dead small, 6TI per cent, more water is evaporated in a given time when the fires are stoked; so, it may be presumed, that had the coal in boxes been stoked, the result would have been better in like proportion. Table No. IV is a condensation of tha Information contained in the reports and tables, and shows at a glance the comparative value of each kind of coal tested. It is interesting to compare the results of minute and elaborate trials at Woolwich, with the trials of the same coal on board local steamers in 1861, (published in the New Zealand Gazette, February 16, 1882,) for It will be seen that in almost every respect they agree exactly. There was only one trial of Stiller coal, as only two tons were sent to England, owing to the difficulty of carrying it from the mine to the port without roads; but it will be seen that even this one trial shows a result almost equal to the best, as it Is only 1 per cent, below Welsh coal In evaporating water in a given time. See table No. IV, 2nd part.) It is rather singular that Mr Trichett In his report says, “.The Buller coal does not cake,” whereas I know from experience that it does cake, but not so freely as the Grey. Possibly it was so much deteriorated before reaching Woolwich that its caking qualities were destroyed. From all the trials, we have a’ right to conclude that West Coast coal is 15 per cent, better than either average North of England or New South Wales coal; and very much superior indeed, in the matter of clinker and ash. This la a matter of the utmost Importance in the Panama service, particularly wheu the whole distance from Wellington to the Isthmus Is to be performed by rather small steamers, without a coaling station. This is expected to occupy about twenty days, and as engines of 500 horse power will probably consume about 60 tons a day, 1,000 tons at least will be required for the run. Now, if West Coast coal was used, there would be a saving of 160 tons on this, and, consequently, 150 tons more space would be available for cargo and passengers. This of itself would bo an important item in the balancesheet of the company.

Coal used. Quantity, Time. ftah ft Clinker. ft*. it. s. fts. North of England.. 10060 0 6Weigh... 80-65 68 3 6-56 New South Wale*.. 88*5 60 IS 8-20 Grey. 87-21 65 63 313 Grey (dead small) 87-43 65 30 3-54 Boiler 83-83 64 13 363