47

C.—3

diamond-drill is an excellent machine for boring for coal through rock of a moderately uniform character; but in using them through rock having alternately hard and soft seams, as generally met with where auriferous and argentiferous lodes exist, the inclination of the drill is to run towards the side where the seam is softest, and instead of the bore going in its initial direction, it may be many feet out of the line when it is down. Diamond-drills have not been used with success in Australia in prospecting for auriferous lodes from the surface, but they could be used successfully in cross-cutting —that is, a horizontal bore can be put through the strata of the rock to cut the lode ; whereas in boring vertically the strata is in general highly inclined, and the tend of the drill is to follow the soft veins when they are leading in or near the same direction as the initial direction of the bore. In reference to the rock at the Thames, it is not stratified, and, therefore, the same objections would not have the same weight as though it was proposed to bore through schist rock; but there are in several places hard dykes or bands lying at high inclinations, which would have the effect on the bore as a highly-inclined stratified rock. The diamond-drill would be useful to test what depth there is of tufaceous sandstone, or whether it is overlying the schist rock at a moderate depth; and there is a possibility of the bore striking a lode, but the chances are remote, and, even if it should do so, the difficulty then is to know the thickness of a lode the drill passes through. If it was to strike a leader only 4m. thick, and follow down the centre of that leader for some distance, the core might show sufficient gold to pay for working if the lode be of moderate thickness, but not if it is only a small leader. A good many bores may be put down before ever a lode is struck, and a large expenditure made in boring without any good result. The boring is undoubtedly cheapest in the first instance, but it is misleading, and nothing certain as to correct results. The mine-managers advocate the sinking of a shaft to the depth of, say 2,000 ft. on the southern end of the lodes in the Queen of Beauty ground. The strike of the reefs is southwards, being shallow and near the surface in the Kuranui Hill, and gradually getting deeper, going in the direction of the Queen of Beauty Mine. This scheme would involve an expenditure of about £100,000 to sink the shaft, erect machinery, and to prospect the ground by drives and uprises. Notwithstanding this large capital, there is a great probability of it being a profitable mining venture, seeing the large quantities of rich ore which have been taken out of the upper levels. By sinking a shaft it would conclusively prove whether the field was worth working or not; and by prospecting it with a diamond-drill, it would mean that if it did not find an auriferous lode after putting down a few bores the tendency would be to put a damper on any company undertaking to prospect the ground thoroughly at a future time. Another scheme is to extend the Moanataiari Tunnel and prospect the back-country. This would prospect the deep levels as well as sinking on the flat. The whole of the ground on the face of the hill, and on the flat where Grahamstown stands, was one time at a much higher elevation, and came by a slide from the top of the range. This is plainly seen by the Moanataiari Slide. The difficulty is to locate the place where the slip originally came from. Mr. Park, the Director of the School of Mines, who has devoted a great deal of time to this subject, thinks that the Moanataiari Slide may have come down from 600 ft. to 800 ft., or oven more. Therefore, by going into the back-country by the extension of the tunnel the deep levels would be tested. But the same difficulty exists here as in the flat. The ground where this extension of the tunnel would have to go through is held in claims, and therefore it would be a difficult matter to arrange about its extension. The present companies would be the only ones directly benefited by gold being got, and the present tunnel is the property of the Moanataiari Company, who are using it daily to take the quartz from their workings to the crushing-battery. Arrangements would have to be made with this company before anything could be done in the matter of formulating any scheme to carry on mining operations from this tunnel. There is no doubt by carrying this adit or tunnel back into the hill it would test deeper levels than could be done by sinking; but there is a possibility of it cutting through the auriferous belt in going back into the range. In order to cut across the different known lodes the direction of the adit would have to be slightly altered, more in a northerly direction, in order to cut through the Golden Age, Eeuben Parr, Orlando, Watchman, Star of the South, Sons of Freedom, Dixon's, and other reefs; but in whatever direction this adit were extended it would pass through claims held by different companies, and arrangements would have to be made with each of them before finally devising any scheme to test the back-country and deep levels from this tunnel or adit. The whole of the ground in the vicinity of the Thames is held in a network of claims by different companies, and each company considers their ground more valuable than the other, so that there is no hope of any definite scheme being submitted until a great many of these companies have amalgamated their interests. At the time of my visit to the field some gentlemen represented to me that an attempt would be made to amalgamate the Queen of Beauty, Saxon, Slay Queen, Victoria, and the Cambria. If such can be done, there is a possibility of some feasible scheme being formulated to test the deep levels on Grahamstown Flat. Some people are in favour of the shaft being sunk in the Queen of Beauty ground, as the strike of all the lodes from the Kuranui Hill is in this direction. The present pumping plant is considered far too expensive to work if a great depth had to be sunk. The present shaft is 640 ft., and lately the pump has only been keeping down the water to the 400 ft. level, and this can be done by working an Bft. stroke, making three and three-quarter strokes ; and it is said the water can be kept]down to the 640 ft. level by working the pump five strokes per minute. The following data as to the quantity of water to be lifted gives some idea of the power that would be required if a shaft were put down to the depth of 2,000 ft., as proposed by some of the mining men in this district. Assuming that it required five strokes on an Bft. stroke to keep the water down, the diameter of the pump being 24in.; then the quantity would be as follows: (?=0034, d' 1 I w, when (?=the number of gallons discharged per minute, d = the diameter of the pump in inches, and.tu==the number of strokes per minute = 0-034x576x8x5 = 783 gallons per minute; but when it is working at the 500 ft. level, 3-J to 3f strokes a minute is sufficient to keep down the water. If 3| strokes be taken, then on the same basis the quantity of water lifted would