§ Mr. Henry Clarkasked the Postmaster-General what research is being carried out in his Department into improved telephone cables which would reduce the cost of laying underground telephone lines in country areas.
§ Mr. Edward ShortThe cost-effectiveness of the materials and methods used in cable construction and laying is under continuing examination by my Department. Typical changes in an advanced stage of development are the replacement of copper conductors by cheaper aluminium and the development of semiautomatic machinery for jointing the wires in multi-pair cables, thus saving both time and money. Cables are being buried directly in the ground by mole-plough. New types of plastic cable duct to replace the traditional glazed earthenware duct are being introduced; the plastic cable ducts can, unlike the earthenware ducts, be ploughed into the ground directly and this will help to reduce costs. The possibilities of sharing common trenches in the ground with other services such as gas and electricity are being explored.