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their works are substantially constructed, and must have cost a considerable sum of money, and they deserve to be well compensated for their venture. Island Block Company.- -Thin company's workings are situate about two miles higher up the river thai) Kirkpatrick and Eddie's claim. The reason of it being termed the Island Block is that the surface indications show that the river at some former period had a different course from the present-one. There is a low depression in the ground on the west side of the river opposite Miller's Mat, and it follows down the valley, leaving high ground between this hollow and the present riverbed, and this joins the present river-bed at or near the place where they have commenced to work. The whole of this land was purchased some years ago by Mr. Joseph Clarke, a Victorian capitalist, and a company was formed in London, which made arrangements with the proprietor to work about five miles of the low valley which is supposed to have been the ancient river-bed, and from where there is a likelihood of their obtaining a very large amount of gold. One of the best hydraujic plants that has ever been used in the colony has been erected here. No expense has been spared in making all the works of a substantial nature. Mr. C. E. Eawlings, the company's engineer and superintendent, informed me that the company had expended, up to the time of my visit, about £21,000. x\ description of this plant and the company's workings are as follows : — Dam. —A dam is constructed on the Eruidburn, at a gorge at the east end of a large flat, in the form of a weir, and when full covers an area of about fifty acres. In ordinary weather, such as is generally found in the spring, autumn, and winter, the water in the Fruidburn is expected to keep up a supply of water in the dam to give about twenty sluice-heads. The dam is built of cement masonry on a solid rock-foundation, and is 17ft. high. The top portion is formed of double timber, and braced to 401b. rails. There are two bays of timber, with a centre pillar. Each opening in the masonry is double-planked with totara timber, and bolted to the iron. The extreme length of the dam is 66ft., with a base of 14ft., and Bft. wide on top ; and it is calculated by Mr. Eawlings that it can.be raised another 4ft. on the top if required. Gate-openings. —There are three gate-openings, one on the bottom, sft. by 2ft., with an iron door, which can be used to empty the dam. The other two openings are into the flume, the lower one being on a level with the main level of the reservoir, so that nearly the whole of the water stored is available for the race. The third opening is situate immediately above the second, and will only be used in the event of more water being required than the second opening is capable of supplying. If at any time it is found necessary to bring in an additional supply from the Tallaburn, the upper opening will then be used. The overflow7 in flood-time goes over the top of the dam. Main Flume. —The main, or weir, flume, which commences at the dam, is laid for 6 chains on the edge of a gorge on a dry-masonry wall. The flume is made of kauri timber, 4ft. wide and 2ft. deep, and tarred throughout, having a fall or gradient of about Sfiii. to the chain. There are two by-washes in this flume for letting out the water when necessary. Water-race. —At the end of the flume coming from the clam there is a solid-rock cutting, and, after crossing a small break where there is 36ft. of boxes sft. wide by 2ft. deep, it crosses the Fruidburn by a flume 144 ft. long, of same dimensions as the previous boxes, with a fall of 2-fin. to the chain, the flume being 60ft. above level of the bottom of the creek. The race is then constructed for 98 chains in earth and rock cutting, with the exception of three short flumes, two of which are over gullies, having a length of 50ft. each, and one along a rocky ledge which is 140 ft. long. These flumes are all sft. by 2ft. and have a fall of 2fin. to the chain. The conduit in earth and rock cuttings is sft. wide by 3ft. deep, with a fall of lin. in the chain. At the end of the 98 chains of conduit there is a fall of 140 ft. over solid rock, then 3 chains of ditching, afterwards a flume 40ft. high and 108 ft. long over a creek, thence 50 chains of ditching, which brings the water to the penstock where the pipes are fixed. The carrying-capacity of the conduit when three-quarters full is said by the engineer to be thirty-three and one-third sluiceheads ; but, judging from the carrying-capacity of the water-races constructed by the Government, and from experiments made as to their carrying-capacity by actually measuring the water in gaugeboxes, this race when running full would only carry about thirty sluice-heads. The company hold the right to twenty-eight sluice-heads from the Fruidburn and twelve sluice-heads from the Tallaburn ; but other previous rights exist from the Tallaburn to the extent of ninety sluice-heads. Penstock. —The penstock at the end of the water-race is 10ft. square, constructed of totara timber, and lined with pine. There are two bell-mouthed pipes fixed into this, which communicate with two mains, one 16§in. in diameter and the other 15in. These mains run side by side for 17 chains, when they join one 16-J-iu. main in a three-way piece. The fall in the double length is 105 ft. The fall in the single main is 600 ft. in 27 chains. At this point there is a second three-way piece, when the water is conveyed in two lines of 15in. pipes for 46 chains, where the one crosses the Clutha Eiver by suspension wire-cables, and the other is divided into two llin. pipes, which have been for prospecting, on the east side of the river. But it is contemplated to also take the second main across the river if more water is required there. Taking Pipes across Clutha Rivet. —There are masonry piers built at each side of the river, and trestles erected on the top of these to the height of 40ft., the timber used being ironbark and kauri. The masonry is built on a solid foundation and laid in cement. Over the top of the piers there are four wire-rope cables, two ropes in each cable, the span between the piers being 462 ft. The cables on the east side of the river are anchored in solid rock; but on the west side of the river the ground is alluvial-drift ground. The mode of anchoring the cable here was to sink a heavy log for a considerable distance in the ground, having a platform on the top and covered over to a great depth with shingle. The total dip in the centre of the cables is 20ft., or about one^-twenty-third of the span, and the pipe is suspended by suspension-rods from the cables on the same principle as the roadway of a suspension-bridge. The temperature affects the length of the. cables every day, and this, together with the slight oscillation of the pipe, makes it difficult to keep the joints of the