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tion has been asked, for relating to the levels, but up to the present time it has not been furnished. This being the only source from which pure water can be obtained in the neighbourhood, it is important for the sake of health that the reserve should be secured. Another application has been received for a grant of £600 for a domestic water-supply at Mackaytown, proposing to extend the Karangahake system. On inspection this was found to be impracticable on account of the small size of the mains, and a scheme was recommended for an independent supply from near the source of Dogherty's Creek, pending levels, &c, being furnished to the department. South Island. The most important work in Otago is the near completion of the Eweburn Reservoir, which was commenced in June, 1898. After an exhaustive examination of the ground by boring and shaft-sinking to ascertain the nature of the bottom for safe foundations, it was decided to construct the embankment of earth with an impervious face of specially puddled clay in preference to the usual manner of a clay or concrete core in the centre of the dam. At first, on account of a doubt of the supply of water being sufficient to fill a higher dam, it was determined to construct only to 50 ft., provision being made in the base for extension, if found to be advisable. Experience proving, however, that, in spite of the low rainfall and comparatively limited catchment-area of the neighbourhood, the enclosure filled very rapidly by the melted snow down the main gully from Mount Ida, directions were given to raise the structure with a 65 ft. bywash level. Although the nature of the bottom had been thoroughly tested before the foundations were commenced, it was found upon excavating that the schist cliff on the western wing was not sound, and in one place an ancient disintegrated slip of loose stone had to be removed and puddled in with clay. No other difficulty was met with until crossing the end of the rock bottom to the eastward of the creek, where the sudden dip of the schist-rock occurs. There a considerable amount of sandy clay had to be removed, and before a safe and firm foundation could be got several tons of puddled clay had to be buried. When carrying along the foundation thrust-wall of the face-core up the spur or eastern wing of the dam, a slip caused by frosts during the severe winter of 1899 buried the working-faces and supply-roads to the dam. On excavating this a soft sandy strata slip was exposed, which had to be cleared out to a firm clay-bed, and filled in with sound puddled clay. These unforeseen difficulties, and some minor ones not needful to mention, have considerably increased the cost on the original estimate. I wish to call attention to the fact that in works of this description, more especially in such a locality—2,2oo ft. above sea-level —the frosts are severe for three months in winter, causing one of the most trying conditions to work under. Several times the operations had to be suspended to avoid unequal subsidence of frozen material and to allow of proper amalgamation of the layers of clay deposited. From the time of excavating for the foundations to laying the outlet-pipes and fixing the sluice-valves, the work has been carried out by day-labour, directed by Mr. Robert Johnson as Inspector under Mr. R. H. Browne, the County Engineer for Maniototo, who has had the immediate supervision of the works. Since then (with the exception of the quarrying and facestone pitching) the work has been done under Mr. Albert Butler by co-operative labour. Some breaks in the steady continuance of the work have occurred, owing to the scarcity of hands during the summer (owing to mining and rabbiting), carts, and adverse weather, but on the whole the work has been fairly satisfactory, and highly creditable to the officers in charge. In some respects the design and construction is a departure from the general method of damconstruction, inasmuch as the impervious portion is on the front of the dam, instead of from the base up through the centre to the crest. To me it is evident that if the core, which is the vital part of the dam, is placed in the centre, all that portion in front of it, unless of impervious material, must become water-logged, and, instead of being a factor of safety, is highly dangerous to stability. In this case, however, the material is so good and well adapted to the purpose that the whole bank is constructed of gravelly clay. Another departure from the usual practice is the method of raising and lowering the inner sluice-valve or gate, and this was an expedient devised on account of the severe frosts during the three or four winter months. To project in the ordinary way a bridge or stage from the crest of the dam to the lifting-gear of the sluice-gate at a height of 70 ft. in such a climate would undoubtedly lead to breaking of gear through the superincumbent weight of ice freezing to the draw-rod, in addition to the weight of rod and strength of gear necessitated by such a lift. A plan was therefore designed, as shown on the drawing, of lifting and lowering the inner sluice-gate by means of an ordinary pinion and rack, the shutter (of boiler-plate) running in a rabbeted frame propelled by a chain wound round the drum and connected to shackled rods running on rollers up the pitched face of the dam and communicating with a hand crab-winch set in the crest. The shutter can be lowered or raised with ease by one man, and the whole gear being under water when the reservoir is full, any danger or inconvenience from frost is avoided, besides the saving of the usual expensive timber structure and screw lifting-gear usually employed for the purpose. The outlet-pipes are ordinary cast-iron socket, 20 in. inside diameter by 12 ft. in length and •|in. thick, lead-jointed in a bed of concrete on a masonry wall founded on the rock-bottom through the base of the dam to the outlet-valves, three in number, connected by means of a breeches-pipe. If the end or working outer-valve gets choked or out of order (as they sometimes do), it can be removed, and the second take its place. The third valve is intended to supply the water in emergencies when by chance the other two are not serviceable. Water has been drawn from the reservoir through the Mount Ida Water-race, and used by the miners round and about Naseby since the outlet-valves were fixed. The total cost of construction up to date has been £13,893, and as it is estimated that the