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Show Wire Cable With "Teeth" of Sand Cuts Out Slate A saw with teeth of sand is used to saw out large blocks in the slate beds of Pennsylvania. This ingenious device consists of a three-strand wire cable, which Is built Into an endless belt. The cable Is guided by orienting pulleys, which ad-Just ad-Just themselves f the face to be sawed. As It arrives at the point to be cut, sand is spilled over the cable by means of a stream of water, the particles of sand lodging In the twists of the cable. The cable drags the sand, under con slderahle pressure and at high speed, against the bed of the slate and rapidly rapid-ly cuts Its way through, the cutting being a trifle larger than the diameter of the cable. The savings effected by this means run into a figure as much as TiO per cent of the usual amount of waste. Experimenting Is going on to work out a method of cutting the slate into the size of sheets to he shipped out bv piling several slabs on top of each other and cutting them all at once with the wire saw. |