Men who made the world smaller

Innovation and the Communications Revolution

五月 7, 2004

There have been many books on the history of communications, covering the whole spectrum from easily readable accounts for the layman to rigorous studies for professionals. John Bray's book falls somewhere in the middle and is unique in two respects. First, much of it is based on the long and personal experience of the author, who, as head of research at the British Post Office, oversaw a considerable chunk of the effort that led to our present global network. Second, the emphasis is on individuals, on the men who made the communications revolution possible. (The author failed to find a single woman who made a major contribution. Alas, after some hard thinking, I had to agree with him.) No fewer than 70 biographies are given, and the index contains as many as 300 names.

Bray has a knack for choosing illustrations. For example, the Punch cartoon of 1879 predicting video conferencing and the photograph of engineer Rudi Kompfner, former director of research at Bell Labs, in characteristic pose, which for me brought back memories of that remarkable man.

Concentrating on the individuals has the advantage of making the story more personal. Bray often succeeds in describing not only technical achievements but characters too. For example he quotes John Pierce on Harold Friis: "I have known cleverer inventors, more abstruse scientists, deeper mathematicians, better politicians and executives of higher degree. I have known no other man who has left as deep and profitable impress on those who worked for or with him, or who had a clearer insight or a surer success in the work he has undertaken."

But there are disadvantages too. The narrative suffers. The biographies would have blended better with the story had the book been twice as long.

As it is, some of the biographies are sketchy and the gaps between them are often inadequately filled.

The book covers roughly the past two centuries. The story starts in the second chapter, which summarises the contributions of those who laid the mathematical and physical foundations. Each of the following 20 chapters is devoted to a separate topic: telegraphy, sound transmission, frequency division multiplex, radio telegraphy, sound radio, television, multichannel telephony, microwave relays, the transistor and the microchip, information theory, switching, satellite communications, long-distance communications by waveguide, optical fibres, visual systems, data communications, the internet, mobile communications and, finally, the future. Bray's choice of subjects is sound; he is right to include long-distance communications by waveguide, even though it never reached production, since it was a near miss.

The technical descriptions are thorough and knowledgeable. The only point where further explanation seems to be needed is in the discussion of information theory. Bray should have made clear that channel capacity is the maximum speed at which, theoretically, a message can be transmitted through a noisy channel without a single error.

Are all the major players included? Kirchhoff and Helmholtz should surely have found a place among those laying the foundations, and the contributions of Gauss and Weber to the electric telegraph should not have been ignored. Of the more recent contributors, Bray should certainly have mentioned Toni Karbowiak of Standard Telecommunications Laboratories, who was the first to call attention to the potential of fibre-optics communications. As early as 1964, he told the Institution of Electrical Engineers that "of all the guides known to date the fibre guide appears to hold most promise, if due to advances in material technology it becomes possible to manufacture cladded fibres having effective loss tangent about two orders of magnitude better than at present".

The book's references to the British Post Office are usually congratulatory. William Preece, its chief engineer in the 1880s and 1890s, is praised for his foresight in helping the young Marconi. But some of his gaffes ("we don't need telephones here because we have a super abundance of messengers, errand boys and things of that kind") go unmentioned; neither does Bray discuss Preece's dogmatic refusal to acknowledge the role of inductance in telephone cables.

When it comes to foreign parts and times of which the author has no personal experience, some of the descriptions are a little careless. For example, the invention of the mechanical (visual) telegraph merits a longer and more accurate discussion, the French revolution did not start in the 1770s and Napoleon III should not be referred to simply as Napoleon. Then there is the case of Caselli A. and Caselli G. who appear in different chapters and are indexed separately but are the same man.

These minor reservations aside, I enjoyed reading the book and came across many unfamiliar details. Anyone who already knows a lot about communications and is interested in history will find the book absorbing.

But I would not recommend it to undergraduates or to recent graduates. They would probably be overwhelmed by the amount of information crowded into a relatively small space.

Laszlo Solymar is emeritus professor of applied electromagnetism, Oxford University.

Innovation and the Communications Revolution

Author - John Bray
Publisher - Institution of Electrical Engineers
Pages - 313
Price - £39.00
ISBN - 0 85296 218 5

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