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would require a building of about 30 ft. wide by 180 ft. long and 20 ft. high, containing a 5-ton-capacity travelling crane for mounting the machinery, and units consisting each of one turbine of 2,500 h'.p. complete; one generator three-phase alternating current taking 2,200 h.p., and delivering at 0-95 efficiency on full load 1,500 kilo-volt-ampere, with 3,000 to 5,000 volts potential; six transformers to raise the tension from 5,000 to 50,000 volts for transmitting purposes; and switchboard complete. Cost of each unit about £10,000. Transmission Line. The line would be supported on strong wooden poles, about thirty to the mile, and at least 25 ft. high above the ground-level. The line would consist of three wires of T 2 n in. in diameter, or six wires of T x w in. in diameter, of soft-drawn pure copper. The insulators would be of the large apron three-bell type, and capable of insulating up to 100,000 volts (the line being 50,000 volts). The line would be provided with at least one lightning-arrester to each wire every mile, and all the necessary safety fuses, &c. The transformers to reduce the potential from 50,000 to 200 volts would be placed in different parts of the town in neat iron constructions, and well insulated. No sub-station would be required for the light or power. Only the street railway would require a sub-station to transform the threephase into direct current at 550 volts tension by means of rotary transformers. Each group of rotary transformers would cost complete £2,000 for a power of 350 h.p., two or three sets being sufficient for the service of the town with thirty miles of road and a ten-minutes service. Forty-five cars at 20 h.p. = 900 h.p. But these come under a separate consideration. This concludes every point of the Waimakariri scheme. Any further information which may be desired I shall gladly furnish. Cost of line, £300 x 40 = £12,000. The whole plant as enumerated above could be put in for a capital of £250,000. Taking interest at 5 per cent., sinking fund at 5 per cent., repairs, &c, at £ 2 per cent., equal to 12 per cent., or £30,000 .. .. .. 30,000 Working-expenses— Chief engineer, salary .. .. .. .. .. 500 Two assistants at £250 each .. .. .. .. .. 500 Three men at £125 each . .. .. .. .. 375 Three linemen at £150 .. .. .. .. .. 450 Office expenses and management .. .. .. .. 1,000 Oil, waste, &c. „. .. .. .. .. .. 1,175 , £34,000 £ The sale of 14,000-horbe power at £7 per annum gives .. .. .. 98,000 Less deductions of working-expenses .. .. .. .. 34,000 Leaves a profit of .. .. .. .. .. .. £64,000 The town would require at the present time— For lighting .. .. .. .. .. .. 2,000 h.p. For tramways .. .. .. .. .. .. 1,000 „ For power, about .. .. .. .. .. .. 3,000 „ Total 6,000 h.p. 6,000 h.p. at £7 = £42,000, or sufficient to pay for the interest and expense of the whole plant. Of course, only part of the machinery can be put in at first, and units could gradually be added to satisfy the demand, which would decrease the interest account for the first years. It may therefore be said that the whole scheme is on a good financial basis. EAKAIA RIVEE. Besides the Waimakariri, I have also inspected the Rakaia River at the point called " the Gorges," where an island is situated in the middle of the river and is connected on each side with the mainland by Government bridges. The quantity of water running through the river can be estimated at at least 6,000 cubic feet of water per second. By building dams across the two arms of the river on each side of the Island, each dam about 300 ft. long, and would require to be 42 ft. high above waterlevel, they would therefore contain about the same amount of concrete as the Waimakariri scheme dam, and the price can be put down as being about the same, or £110,000. This 6,000 cubic feet of water with 42 ft. fall would give us about 20,000 h.p. delivered in the City of Christchurch at practically the same total cost. The water in the river should be banked up 42 ft., and surveys should be made to ascertain the value and area of Mr. McLean's property, which is situated behind the second gorge, and which will be partly swamped, and for which damages will have to be paid. This Rakaia scheme certainly presents advantages over the Waimakariri in so far that it would be much easier to build the whole hydraulic works, having the two arms of the river ; the water could be ejected by one arm while the other was being built—facilities which we have not got in the Waimakariri scheme. The power-station could be installed at the bottom of the cliff on the small

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