NOVEL STONE-COLLECTING

Taranaki Daily News, 30 January 1931, Page 9

NOVEL STONE-COLLECTING

MANGAMAHOE DAM PAVING RAILS AND ELECTRIC HAULAGE. DECREASE IN WATER SEEPAGES. The Mangamahoe dam presented a scene of renewed activity yesterday when ths new facilities for securing the stone for the paving of the inner embankment of th© dam were in operation. In order to hasten tile completion of the paving, which it is estimated will still take a fortnight, the contractors (Messrs. J. T. Julian and Son) have run a tram line along the entire length of the fpp of the dam. At a point immediately above tire diversion tunnel that runs underneath the dam a powerful electric motor and winch have been installed. A short section of tramline at this point revolves on a turntable and gives rail connection with another tramline running at right angles down the step lower face of the dam to the mouth of the diversion tunnel and thence down the more or less dry bed of the former Mangamahoe stream. Explosives and drills operated by air-compressor have been used in the strcam-bed to fracture the hard rock lying there, and all along the bed are heaps of this stone reduced by hand spawning to the' size required for paving. Four email trucks, worked in two trains of two trucks each, are in operation on this section of tramline for the haulage of the metal to the top of the dam. The loaded trucks are drawn up by a stout wire cable attached to the winch at the top, and- when empty the trucks run down again at great speed by force of gravity, tho restraining wire cable being paid out ..fairly gently to prevent them running off the rails altogether. The “stationmaster” on the top of the dam has a fairly busy , time superintending the operation of the motor and winch and changing over the full and empty trucks from the one set of rails running down the side of the dam to the other running along the top of the dam. A miniature petrol-burning railway engine was standing at one end of the upper tramline yesterday, but it was not quite ready to be put into commission, From the "station” the trucks fun to and fro (by man-power yesterday) to a point at the eastern* extremity of the dam near the spillway, where the paving is actually in progress at present. The ‘Work of placing the stone in position could not have' been a very pleasant one yesterday for • the water of tho lake, though it is still being held a foot beloW the level of the spillway, has almost caught up at that point to the work of paving. . A etiff westerly wind was causing substantial waves to foil in, and the meh working near the writer’s edge did not exactly have a dry job. The use to which the lake is being put was apparent yesterday during the peak loading period, whdn water whsflowing freely from the lake, over the northern spillway of the rriain race, thence into the mouth of No. 2 tunnel rind- so through to the forebay and down to the power-house. The seepages of water that manifested themselves at the end of last week oh the . lower sides of 'both the southwest embankment and the mriin dam have not increased this week. On the other hand they scCm tb have diminished a little, arid it is hoped that this is a sign that the crevices are gradually being silted up. Not' much change has occurred in the jets of water coming through the roof of the diversion tunnel, and .as at the present stage they ai‘e not Considered to be a cause Of concern a few holes are to be drilled in the concrete to allow the water to escape more freely.