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A plant and works to yield 8,500 b.h.p. on turbine-shafts for continuous working would cost, say, £350,000. Of this amount, £250,000 would be for dam, tail-race, conduit, buildings, &c, and £90,000 for electric plant, transmission-line, substitutions, &c. For an installation to work up to, say, 17,000 b.h.p. on turbine-shafts the cost would be about £470,000. Of this, £286,000 would be for dam, conduit, tail-race, buildings, and minor engineering works. No sums have been included in the above estimates for secondary distributing-lines in the towns; these would amount in time to a considerable sum—for these lines would year by year increase in number and length until the power was fully utilised. To compete with steam and gas the power must be sold at a low rate to consumers. In this connection it is worthy of note that three electric horse-power are equal as a rule to displacing four steam horse-power owing to saving in losses due to belts and shafting, and in addition there is no doubt but that even on the above high costs for installation, power can be supplied at a profit if sold at the consumers' meters for £7 per horse-power year for continuous working, and for shorter-time service, eight hours per day, £5 per horse-power, and perhaps slightly higher rates for intermittent working. The probable revenue would be, at these rates, over £50,000 when all the energy was sold. The Hutt scheme derives its importance from its very favourable situation. The cost per horse-power is high, but the working-costs will be lower than if an equal amount of money were expended in obtaining an equal amount of power from a long-distance-transmission scheme, and I have no hesitation in recommending its adoption in preference to any such scheme, on the grounds of probable lesser cost for power supplied, and the certainly much less risk of interruption of service by failures in the transmission-lines. In Wellington City, Petone, and the Hutt Valley about 19,000 h.p. are in use exclusive of railway locomotives. The power obtainable at the Hutt would not supply all this demand, nor is it likely that all the existing power would be converted to electro-motive power. A scheme that would now provide 10,000 to 15,000 h.p., and that could as time went on be gradually enlarged to double or treble the size would be preferable, but so far no such scheme has been discovered near Wellington, and, supposing one scheme started, additional power —so long as existing conditions obtain—would have to be got by adding future schemes, as Tauherenikau, Mangahao, &c, to supply the needs of the district. The nearest large scheme is the Mangawhero-Wanganui—this would be 120 miles distant; then Waikaremoana, about 240 miles distant; and Huka, 250 miles distant by the east, and 210 miles by the west coast. If the Mangawhero scheme were to prove a good one, the cost for power might be about as low as the cost from the Hutt scheme, while for Huka and Waikaremoana the cost would be probably 40 per cent, greater than the Hutt costs, though this might be reduced if excessive voltages were found to be practicable under all New Zealand conditions— which would be severe, as the transmission-lines would be near the sea for "considerable distances. There is, however, not enough power available at Huka to justify the construction of radiating transmission-lines to Auckland, Wellington, and other centres. Waikaremoana is the only scheme which could be considered in connection with any proposal to serve all the North Island from one power-station. Clarence. The surveys at Jollies Pass and Jack's Pass show undoubtedly that Jollies Pass is the better location for a power scheme, there being here more power available at less cost. The works required are a weir across the Clarence River about half a mile above the junction of Jollies Pass creek with the river, an intake to draw off all the low-water flow of the river through the shingle that must certainly accumulate to the level of the top of the weir, settlingbasins sufficiently large to allow of the heavier grit being taken out of the water before it enters the tunnel. These works would be common to any works adopted. There are two alternative routes for the tunnel through the range—one leading to a spur down which the stock-track runs. On this route the tunnel would be 133 chains long in one length. Beyond this it would be advisable to continue the tunnel for a further length of about 59 chains, and excavate it from several drives in from the face of the spur. Open fluming, or perhaps a race in places, could be substituted for this length of tunnel, but the tunnel would involve practically no risks of breakdown. From the end of the second tunnel the ground falls very rapidly —in 40 chains, 966 ft.; in 60 chains, 1,071 ft.; and in one mile, 1,134 ft. Over any part of this section steel pipes must be used. The other alternative is to take the conduit along a ridge, the next on the south of the stock spur. The tunnel through the main range is 2 chains shorter than in the first case, being about 131 chains long. A prolongation of the tunnel in this case also would likely be advisable, but this length would only be about 32 chains long, or 165 chains of tunnelling against 192 chains on the other route. From the end of the tunnel the ground falls in the first half-mile 975 ft., and in 52 chains 1,037 ft. By the construction of a dam across Lake Tennyson outlet to raise the water-level by about 35 ft. storage would be provided to give water enough to increase the power up to 31,000 b.h.p. at least. The cost of such a dam would not be very great; the most troublesome part would be the flood-water overflow. The area of the lake is about 091 square miles at low water, and about 1\ square miles at 50 ft. above low-water level. The drainage-area above the lake is probably not more than twenty-six square miles. A high rainfall may be expected, as the elevation is high, and snow' will help to maintain the river-flow at some seasons. The cost of this dam would be about £35,000. There are two periods of high flow in the river, and probably two fills or more of the reservoir would be had each year. Long-continued frosts might have some ill effects on the flow.