0.—3

22

points where the siphon would join the ditching : with this fall a pipe 24in. in diameter would be sufficient to convey about twenty-five sluice-heads of water. The original dimensions of the open channel were 4ft. wide in the bottom, 7ft. wide on the top, and 3ft. deep, with a fall of 7ft. per mile. Assuming that the actual depth of water was 2ft. 6in., then the width on top of the water would be 6ft. 6in., or a sectional area of about 13 square feet. Taking the fall per mile and frictional surface into consideration, the carrying-capacity of the ditch ought to be about twentysix sluice-heads, whereas it is reduced to a carrying-capacity of only from twelve to fifteen sluiceheads. Constant Supply of Water. —There is frequently not sufficient water in the different streams to fill the ditch, and, unless a storage-reservoir is constructed to store the water in wet weather, a constant supply cannot be obtained. But if the water were conveyed across the shingle-beds of the different creeks in iron or steel piping, and the water of the creeks lifted into the race close to the foot of the range, where a rock bottom can be obtained, a far more regular supply would be insured. The ditch requires cleaning out from end to end, and the lower side closely examined to see that all the rabbit-burrows are stopped up. If this is not attended to a considerable leakage is bound to occur. At the place where the water is lifted out of the middle branch of the Manuherikia Eiver there is, and always will be, a certain loss of water until better provision is made to turn it into the race. At present) there are only a few stones laid across the bed of the stream, with shingle and sods laid against them. There should be a. solid wall of concrete, if a foundation can be got, across the bed of the stream, with an intake-gate at the head of race, the wall to be so constructed as to act as a weir when there is more water in the river than the ditch can carry. Eweburn Reservoir. —ln regard to a storage-reservoir, there is a very good site at the Eweburn, with solid-rock abutment on one side, and, apparently, rock on the other ; but this is not certain, as there is a low saddle projecting behind the block of rock, which has the appearance of being the former bed of this creek. According to a survey made by Mr. E. Brown, a reservoir could be constructed for £10,000, which would have a storage-capacity of 57,000,000 cubic feet of water, and would give a supply of fifteen sluice-heads of water for eight hours a day for a period of seventy-eight days, after allowing 40 per cent, for absorption and evaporation. There is, however, a doubt in my mind as to whether a good foundation for the embankment of the reservoir on the Naseby side of the Eweburn can easily be got. A few shafts would require to be sunk to test this before a reliable estimate could be given of the cost of construction ; and, as these shafts could be put down for very little expense, the work should be undertaken : this could be done during the winter months, when mining cannot be carried on for the frost. Surprise Water-race. —Ever since the construction of the Mount Ida Water-race, the Trust has always complained about the agreement made with the proprietors of the Surprise Water-race to carry a certain quantity of water from the Eweburn free of charge. This was owing to the Mount Ida Eace being only at about from 6ft. to Bft. on a higher level, and in following round the contour of steep sidelings the excavated material filled up the Surprise Eace. Consequently, an arrangement was made with the proprietors of this race to abandon it, and the Government agreed to convey two sluice-heads from the Eweburn, when there was water in this creek, and deliver it to the proprietors of the Surprise Water-race, free of charge, at their dam near Naseby. This water has been supplied for the last fifteen years; but in February last the Government purchased the rights of this water-race for £590. At that time there was an arrangement to lease the right of water coming to the proprietors of the Surprise Eace to Jacob Lory, for twelve months. The Government has carried out that arrangement, and. leased the right to the water that the late proprietors were entitled to for £55 per annum. The lease expires on the 27th January, 1893. R. Johnstone's Wetter-rights. —As stated elsewhere, E. Johnstone holds two water-rights, and has two water-races constructed, one from Marion Burn, or eastern branch of the Manuherikia Eiver, and another from the Ida Burn. At the time of my visit to the district there were about five sluice-heads of water in each of those water-races; but this quantity only holds good for a short time after rains. The Miners' Association advocate the purchase of Mr. Johnstone's water-rights from the Marion Burn, for which he requires about £2,000. In regard to the extra supply of water that can be got out of the Marion Burn, it would make very little difference to the extra quantity of water in the Mount Ida Water-race, inasmuch as in ordinary weather, when there is a supply in the Marion Burn, there is a good supply of water in the Mount Ida Eace, and when the water becomes short in the race there is very little to be got from the Marion Burn. As a constant supply is desired, the reservoir at the Eweburn is by far the best way of obtaining it. On examining the stream flowing down the valley of the Eweburn, it struck me that it was questionable whether a supply of water could be got from it to fill this reservoir; but the present Manager of the race, as well as the County Engineer and the Chairman of the Trust, assured me that a large body of water comes down this stream in time of floods and wet weather, and that there will be no difficulty in getting the reservoir filled at least once a year; which would mean about three months' supply of water for the field. Estimated Revenue. —From what could be gathered from the manager of the water-race, if there were a constant supply of fifteen sluice-heads of water for ten months in the year, I understood that the revenue from sales of water would amount to £1,700 per annum, while the expenditure would be about £1,100. Judging from the appearance of the ground, and considering that larger quantities of water would be used if available, the race should be cleaned out to its original dimensions, which would give it a carrying-capacity of about twenty-six sluice-heads when water was available. Indeed, it would be good policy to distribute extra water amongst the miners at first free of charge when the same was available, as this would demonstrate the extra quantity of ground that could be operated on with a larger supply of water, and eventually lead to more water being used, thereby ultimately increasing the revenue. If this race were maintained and managed