Telephone research began in 1876 in the Boston attic where Alexander Graham Bell carried on his first successful experiments on the “electric speaking telephone.” From Bell’s modest beginning has evolved the Bell Telephone Laboratories of today, where over 9,000 scientists, engineers, technicians and auxiliary personnel constantly seek ways to improve telephone service, widen its usefulness, and keep its cost low.
Some members of the Laboratories are engaged in basic research. They explore the physical sciences—physics, mathematics, chemistry—seeking basic knowledge that may contribute to better communications. Fundamental development is the second step in the chain leading toward manufacture and use. In the third step, groups engaged in systems engineering plan how the new knowledge and discoveries of research can be used to create new facilities for telephone service, improve service, or reduce costs. Final step is the specific development and design of new systems or products. This involves the construction of laboratory models, trial models, service tests, and preparations for mass production.
This description is, of course, a highly simplified account of the work of the Laboratories. The broad functions of research and development constantly merge. At all times there must be close co-operation among various groups in the Laboratories, between the Laboratories and the telephone companies, where models are tried out, and between the Laboratories and Western Electric, where products are manufactured.
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.