How many phone calls can an underwater cable carry?
Undersea telegraph cables came first, long before the first telephone cable was laid on the floor of the ocean. For years, all overseas calls traveled by radio. Now some of these calls are carried by cable and better cables of the future will carry many more of them. Overseas telephoning grows more popular every year. In 1964, Americans had almost 6 1/2 million conversations with their friends across the oceans. It is estimated that in 1970 the number of these calls will reach about 15 million. Extra circuits to carry them by radiotelegraph are being installed all the time. And in the past ten years, more than 600 snore telephone cables have been laid across the floors of the oceans. Naturally, these systems are improved constantly with new inventions. An underwater cable of the future promises to carry over five times as many calls as the best ones of today. The first transatlantic telephone cable was ready for conversations in 1956. It was able to carry 36 conversations at the same t
