Abstract :
TELEPHONE CABLES containing large groups of insulated conductors in a common sheath have been developed rapidly since 1882; previous to that time all telephone distribution was by means of overhead wire plant. The present maximum sized cables in use contain 1,818 pairs of 26-gage conductors in a sheath having an outside diameter of 2 5/7 in. The increase in the amount of cable in plant during the past decade in certain metropolitan areas, such as Baltimore, Md., and Washington, D. C, has been over 100 per cent, and at the present time the value of the cable plant represents about 25 per cent of the total plant investment in these areas.