Abstract :
WITHOUT increasing the diameter of its largest telephone cable from the former size of 2⅝ inches, the Bell System has increased the number of separately insulated copper wires within the cable from 3,636 to 4,242. The diameter of the wires also remains unchanged. The addition of 303 pairs of wires within the same girth of cable was accomplished by an improved technique of insulation which reduced the thickness of insulation around each wire by 0.003 inch.
