Here is just one example of the way research and development have extended telephony, improved it, and reduced its cost: Many years ago, the use of a pair of wires instead of a single, grounded wire greatly improved transmission and made it possible to talk longer distances. This increased the demand for service but also increased the number of wires strung on telephone poles. The large number of wires on towering poles along city streets began to cast shadows of doubt on the prospects for further growth. Compact cables had to be developed and a way found to run them underground. Years of painstaking study and trial accomplished this. Now some exchange cables contain as many as 2,121 pairs of wire. This cable evolution illustrates the dollar value of telephone research and development. The standard cable of 1888 contained 50 pairs of wires and its installed cost was more than $150 per pair-mile. In 1954, despite rising costs, underground cable cost in the order of $20 per pair-mile in place, and much of it was 2,121-pair. A few milestones in research Through the years Bell Laboratories has led progress in communications and electronics. No scientific achievement has had more far-reaching effects on communications than the Laboratories’ work in the development of the vacuum tube. Bell scientists were the first to devise a practical amplifier tube which, placed at intervals in long distance lines, restored the energy of weakening voice currents, making it possible to telephone from coast to coast. The Laboratories was the first to develop automatic equipment that can “remember” telephone numbers and perform other complicated operations in the central office. By means of filtering apparatus, developed by the Laboratories, one high frequency “carrier” can carry many speech currents at the same time. Largely because of carrier telephony, the Bell System has been able to reduce greatly the cost of long distance telephone service. The Laboratories pioneered the development of coaxial cable and microwave radio-relay systems. Both can be used to transmit television programs and hundreds of telephone conversations. Among the many other achievements of the Laboratories have been important contributions to the design of computers—the amazing electronic machines that can work out problems that might otherwise take months or years of work by mathematicians. A few years ago, scientists at the Laboratories invented the _transistor_. This is a radically new device, simple in design and tiny in size, that performs most of the functions of the vacuum tube and does other things besides. Its effect on communications technology promises to be revolutionary.