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yield 8 cubic feet a second. As he says in his report of the 12th March, 1888, that he measured the water that would flow in , the high Mikonui Eace, and found it to be 6 cubic feet a second, I think his statement may be relied on, that 53 heads would be the supply in driest weather, and 8 cubic feet a second for the greater part of the year. " To provide water for winding up the washdirt there are two alternatives, either of which leaves a deficiency in the driest weather of water to wash and sluice the washdirt or wind it up from below. In the first alternative water from the right-hand branch, which at present is brought across Donnelly's'Creek in a 15 in. pipe and delivered into the No. 1 race, would give 2 cubic feet, and water picked up between the Mikonui intake and that of No. 1 race is said to yield 1 cubic foot, or 3 cubic feet altogether, and the height of No. 1 race above the proposed site of the windingengine would be 170 ft., the effective horse-power of which would be about 38-horse power—barely enough for the power required, which, as above mentioned, is stated to be 42-horse power. But this leaves no water for washing in dry weather. The second alternative is to take the excess of water yielded in ordinary weather at the high Mikonui Eace. This was stated above to be 8 cubic feet, and the quantity required for pumping to be 53 heads or cubic feet a second. The excess is, therefore, 2-8 cubic feet, and the head is 400 ft., because in this case the winding-engine could be placed at the top of the tip where washing is to be done, or 175 ft. higher than the position mentioned in alternative No. 1. Taking only 2 cubic feet of the 2-8 supposed to be available, with a head of 400 ft., would give a theoretical power of 86-horse power, and 66 per cent, of this would be the effective power for work, equal to 56-horse power, the power required being, as above, 42-horse power. This leaves the water of the right-hand branch, stated above to be about 3 cubic feet, with a height of 170 ft., and running in No. 1 race, to be used for washing the dirt. But this second alternative leaves no water for winding in dry weather. " Messrs. Waters's, Wylie's, Grimmond's, and my investigations all point to the conclusion that the water-supply is barely enough in the dry weather for all the operations, and, although there is ample for pumping, work, if dependent on water only for power, might be stopped for a short time perhaps every year. Mr. Grimmond thinks, and, I believe, with reason, that in very dry weather the underground water would diminish in proportion as the supply for power purposes did, and thus the water-power available might always be sufficient. " I will not attempt to express any opinions on the style of water-engines that should be used, except to state that the engines used, and now standing in the shaft, never gave satisfaction, although Messrs. Waters and Wylie were of opinion that they could be so altered as to be serviceable, recommending at the same time that much longer water-cylinders should be provided. But I think, if new engines are to be designed, some form of common Cornish pit-pumps, driven by turbines or Pelton wheels, if such could be adapted to the position, would be much more reliable and easier managed. " If this property is to be worked on a payable scale, it will be necessary to comply with the mining regulations and sink another shaft. I agree with Mr. Grimmond that it would be best to put the pumps in the present shaft and pump it dry, and then the second shaft can be easily sunk, as the ground would be nearly free of water. As Cassius's shaft and workings are standing full of water, if this is not pumped out the water must be relied on to percolate slowly into the pumped-out shafts, with the liability of an outburst suddenly into the pumping-shaft. There was reason to believe, when the Eoss Company were working at the bottom of their shaft, that water was pouring into it from Cassius's workings. If so, these workings might be drained by pumpingin the Eoss Company's shaft until Cassius's workings were dry; but, if the water refused to pass through, and stood in Cassius's workings, there would always be a risk in working the shaft, and means would have to be taken to free Cassius's workings of water. " From the above investigations it is quite evident that the water-supply available from Donnelly's Creek and its tributaries is just about enough to keep Eoss Flat drained to the deep levels, and enable the Eoss United Company to carry on all their necessary operations ; but there is no water to spare for any other parties to join in working other parts of the flat, which I understand is one of the objects the Government had in view when proposing to assist the Eoss United Company by a subsidy. It is shown that it will most likely tie necessary to provide for extending the working seaward of the shaft, and for this purpose : that power should be provided to sink the shaft 100 ft, deeper than is contemplated in this report. But unless the water met with underground proves to be much less than the 1,900 gallons a minute herein assumed, then there is not power enough to be got out of water derived from Donnelly's Creek and its tributaries. Some time ago Mr. Grimmond proposed that water should be taken from the Mikonui Eiver at a place called "the Gorge," and brought in a race to the site of the old overshot-wheel of the Koh-i-noor Company at Black's Creek, there to be employed in driving a turbine or Pelton wheel, which should generate electric power, to be conveyed by wire to the Eoss Company's shaft, and there used to drive the pumping machinery. The Mikonui Eiver is said to carry in ordinary weather about 300 cubic feet a second, and when I saw it at the Gorge it appeared to me that it was running about that quantity. Persons long resident in the locality estimate that in the driest weather it carries never less than 100 cubic feet. " A water-race, called the Prince of Wales, was surveyed from the Prince of Wales Claim, near Eoss, up to the gorge of the Mikonui at an inclination of 8 ft. per mile. This race is constructed as far as 17 chains beyond Italian Gully, but is not used by the Prince of Wales Company any further than Black's Creek. At Black's Creek the height of this race above the available discharge at the old overshot-wheel is said to be 62 ft., but, as I could find no levels, this height requires to be verified. If 55 cubic feet a second were taken out of the river at the Gorge by completing the Prince of Wales Eace or constructing a new race to there, this water, with a fall of 60 ft., will give a