A MeMber of the Perseus books Gr ou P www.westviewpress.com www.perseusacademic.com

“A welcome update to the classic text on the history of the computer— sure to extend its relevance to a new generation of students and scholars.”

—DaviD MinDell, MiT, auThor of Digital apollo: Human anD macHine in SpacefligHt

“This authoritative yet accessible history of computing improves with each edition. This latest version provides enhanced coverage of recent developments such as the Internet, while sharpening and deepening its treatment of earlier events. A balanced, reliable account that holds interest for specialists and provides a ready entry into the

topic for students, professionals, and general readers.” — STeven W. uSSelMan, GeorGia inSTiTuTe of TechnoloGy

Computer: A History of the Information Machine traces the history of the computer and shows how business and government were the first to explore its unlimited, information-processing potential. Old-fashioned entrepreneurship combined with scientific know-how inspired now famous computer engineers to create the technology that became IBM. Wartime needs drove the giant ENIAC, the first fully electronic computer. Later, the PC enabled modes of computing that liberated people from room-sized, mainframe computers.

This third edition provides updated analysis on software and computer networking, including new material on the programming profession, social networking, and mobile computing. It expands its focus on the IT industry with fresh discussion on the rise of Google and Facebook as well as how powerful applications are changing the way we work, consume, learn, and socialize. Computer is an insightful look at the pace of technological advancement and the seamless way computers are inte- grated into the modern world. Through comprehensive history and accessible writing, Computer is perfect for courses on computer history, technology history, and information and society, as well as a range of courses in the fields of computer science, communications, sociology, and management.

MArTIn CAMpbell-Kelly is emeritus professor of computer science at the University of Warwick.

WIllIAM AsprAy is Bill and Lewis Suit Professor of Information Technologies at the University of Texas at Austin.

nAThAn ensMenger is associate professor in the School of Informatics and Computing at Indiana University Bloomington.

Jeffrey r. yosT is associate director of the Charles Babbage Institute and faculty member in the History of Science, Technology, and Medicine at the University of Minnesota.

COvEr IMAGE © SHUTTErSTOCk COvEr DESIGN: MIGUEL SANTANA & WENDy HALITzEr

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COMPUTER

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COMPUTER A History of the

Information Machine

THIRD EDITION

Martin Campbell-Kelly William Aspray

Nathan Ensmenger Jeffrey R.Yost

A Member of the Perseus Books Group

THE SLOAN TECHNOLOGY SERIES

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WESTVIEW PRESS was founded in 1975 in Boulder, Colorado, by notable publisher and intellectual Fred Praeger. Westview Press continues to publish scholarly titles and high-quality undergraduate- and graduate-level textbooks in core social science disciplines. With books developed, written, and edited with the needs of serious nonfiction readers, professors, and students in mind, Westview Press honors its long history of publishing books that matter.

Copyright © 2014 by Martin Campbell-Kelly and William Aspray

Published by Westview Press, A Member of the Perseus Books Group

All rights reserved. Printed in the United States of America. No part of this book may be reproduced in any manner whatsoever without written permission except in the case of brief quotations embodied in critical articles and reviews. For information, address Westview Press, 2465 Central Avenue, Boulder, CO 80301.

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Library of Congress Cataloging-in-Publication Data

Campbell-Kelly, Martin. Computer : a history of the information machine / Martin Campbell-Kelly,

William Aspray, Nathan Ensmenger, and Jeffrey R. Yost. — Third edition. pages cm

Includes bibliographical references and index. ISBN 978-0-8133-4590-1 (pbk. alk.) — ISBN 978-0-8133-4591-8 (ebook) 1. Computers—History. 2. Electronic data processing—History. I. Aspray,

William. II. Ensmenger, Nathan, 1972– III. Yost, Jeffrey R. IV. Aspray, William. V. Title. QA76.17.C36 2013 004—dc23

2013008040

10 9 8 7 6 5 4 3 2 1

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CONTENTS

Acknowledgments vii Preface to the Third Edition ix Introduction xi

Part One: BEFORE THE COMPUTER

1 When Computers Were People 3 2 The Mechanical Office 21 3 Babbage’s Dream Comes True 41

Part Two: CREATING THE COMPUTER

4 Inventing the Computer 65 PHOTOS: From Babbage’s Difference Engine to System/360 87 5 The Computer Becomes a Business Machine 97 6 The Maturing of the Mainframe: The Rise of IBM 119

Part Three: INNOVATION AND EXPANSION

7 Real Time: Reaping the Whirlwind 143 8 Software 167

PHOTOS: From SAGE to the Internet 189 9 New Modes of Computing 203

Part Four: GETTING PERSONAL

10 The Shaping of the Personal Computer 229 11 Broadening the Appeal 253 12 The Internet 275

Notes 307 Bibliography 327 Index 343

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ACKNOWLEDGMENTS

THIS BOOK has its origins in the vision of the Alfred P. Sloan Foundation that it is important for the public to understand the technology that has so profoundly re- shaped Western society during the past century. In the fall of 1991 Arthur Singer of the Sloan Foundation invited us (Aspray and Campbell-Kelly) to write a popular history of the computer. It was a daunting, yet irresistible, opportunity. Without the invitation, encouragement, generous financial support, and respectful treat- ment we received from the Sloan Foundation, this book would never have been written.

It is a pleasure to thank many academic colleagues who, over three editions of Computer, have given us advice or checked sections of our manuscript; among them: Jon Agar, Kenneth Beauchamp, Jonathan Bowen, I. Bernard Cohen, John Fauvel, Jack Howlett, Thomas Misa, Arthur Norberg, Judy O’Neill, Emerson Pugh, and Steve Russ. Our thanks go to numerous archivists who helped us to lo- cate suitable illustrations and other historical materials; among them: Bruce Bruemmer and Kevin Corbett (formerly at the Charles Babbage Institute), Arvid Nelsen (Charles Babbage Institute), Debbie Douglas (MIT Museum), Paul Lasewicz (IBM Corporate Archives), Henry Lowood (Stanford University), Erik Rau (Hagley Library), Dag Spicer (Computer History Museum), and Erica Mosner (Institute for Advanced Study, Princeton). For the first edition of this book Susan Rabiner of Basic Books took us by the hand and coached us on how to write for a general readership. Our successive editors at Westview Press have been a source of wisdom and encouragement: Holly Hodder, Lisa Teman, Priscilla McGeehon, Carolyn Sobczak, and Christine Arden. Notwithstanding these many contribu- tions, we take full responsibility for the contents.

Martin Campbell-Kelly William Aspray

Nathan Ensmenger Jeffrey R. Yost

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PREFACE TO THE THIRD EDITION

SINCE THE appearance of the second edition in 2004, computing has continued to evolve rapidly. Most obviously, the Internet has grown to maturity such that it is now an integral part of most people’s lives in the developed world. Although com- puting was widely diffused by the end of the twentieth century, it has become truly ubiquitous only in the present century—a transition brought about by Internet commerce, consumer computing in the form of smartphones and tablet computers, and social networking.

The study of the history of computing has also matured as an academic enter- prise. When the first edition of this book appeared in 1996, the history of comput- ing had only recently begun to attract the attention of the academy, and research on this topic tended to be quite technically oriented. Since that time many new scholars with different perspectives have joined the field, and it is rare to find a sci- ence, technology, or business history conference that does not discuss develop- ments in, and impacts of, computing technology. In short, the user experience and business applications of computing have become central to much of the historical discourse. To harness these new perspectives in our narrative we have been joined by two additional authors, Nathan Ensmenger and Jeffrey Yost—both scholars from the rising generation.

As always in a new edition, we have sparingly revised the text to reflect changing perspectives and updated the bibliography to incorporate the growing literature of the history of computing. We have also introduced some substantial new material. In Chapter 3, which focuses on the precomputer era, we have added a section on Alan Turing. The year 2012 saw the centenary of the birth of Turing, whom many consider both a gay icon and the true inventor of the computer. Turing was indeed a key influence in the development of theoretical computer science, but we believe his influence on the invention of the computer has been overstated and have tried to give a measured assessment. In Chapter 6, on the maturing of the mainframe computer, we have condensed material on the computer industry in order to make space for a discussion of the diffusion of computing in government and business or- ganizations and the development of the computer professions. In Chapter 7, on real-time computing, we have taken advantage of a new strand of literature to dis- cuss the development of online consumer banking. In Chapters 8, 9, 10, and 11 we

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have made substantial additions to exploit the growing literature on the software professions, the semiconductor industry, pre-Internet networking, and the manu- facture of computers.

Unsurprisingly, Chapter 12, on the development of the Internet, is the most changed. The chapter has been extended and divided into two parts: the creation of the Internet, and the World Wide Web and its consequences. The latter part in- cludes new material on e-commerce, mobile and consumer computing, social net- working, and the politics of the Internet. It is extraordinary to think that when we were writing the first edition of this book in the early 1990s, the web had only just been conceived and its current ubiquity was beyond our imagining.

With these changes we hope that, for the next several years, the third edition of Computer will continue to serve as an authoritative, semi-popular history of computing.

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INTRODUCTION

IN JANUARY 1983, Time magazine selected the personal computer as its Man of the Year, and public fascination with the computer has continued to grow ever since. That year was not, however, the beginning of the computer age. Nor was it even the first time that Time had featured a computer on its cover. Thirty-three years earlier, in January 1950, the cover had sported an anthropomorphized image of a computer wearing a navy captain’s hat to draw readers’ attention to the feature story, about a calculator built at Harvard University for the US Navy. Sixty years before that, in August 1890, another popular American magazine, Scientific Ameri- can, devoted its cover to a montage of the equipment constituting the new punched-card tabulating system for processing the US Census. As these magazine covers indicate, the computer has a long and rich history, and we aim to tell it in this book.

In the 1970s, when scholars began to investigate the history of computing, they were attracted to the large one-of-a-kind computers built a quarter-century earlier, sometimes now referred to as the “dinosaurs.” These were the first ma- chines to resemble in any way what we now recognize as computers: they were the first calculating systems to be readily programmed and the first to work with the lightning speed of electronics. Most of them were devoted to scientific and military applications, which meant that they were bred for their sheer number- crunching power. Searching for the prehistory of these machines, historians mapped out a line of desktop calculating machines originating in models built by the philosophers Blaise Pascal and Gottfried Leibniz in the seventeenth century and culminating in the formation of a desk calculator industry in the late nine- teenth century. According to these histories, the desk calculators were followed in the period between the world wars by analog computers and electromechanical calculators for special scientific and engineering applications; the drive to im- prove the speed of calculating machines during World War II led directly to the modern computer.

Although correct in the main, this account is not complete. Today, research sci- entists and atomic weapons designers still use computers extensively, but the vast majority of computers in organizations are employed for other purposes, such as word processing and keeping business records. How did this come to pass? To

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answer that question, we must take a broader view of the history of the computer as the history of the information machine.

This history begins in the early nineteenth century. Because of the increasing population and urbanization in the West resulting from the Industrial Revolution, the scale of business and government expanded, and with it grew the scale of infor- mation collection, processing, and communication needs. Governments began to have trouble enumerating their populations, telegraph companies could not keep pace with their message traffic, and insurance agencies had trouble processing poli- cies for the masses of workers.

Novel and effective systems were developed for handling this increase in infor- mation. For example, the Prudential Assurance Company of England developed a highly effective system for processing insurance policies on an industrial scale using special-purpose buildings, rationalization of process, and division of labor. But by the last quarter of the century, large organizations had turned increasingly to tech- nology as the solution to their information-processing needs. On the heels of the first large American corporations came a business-machine industry to supply them with typewriters, filing systems, and duplication and accounting equipment.

The desk calculator industry was part of this business-machine movement. For the previous two hundred years, desk calculators had merely been handmade cu- riosities for the wealthy. But by the end of the nineteenth century, these machines were being mass-produced and installed as standard office equipment, first in large corporations and later in progressively smaller offices and retail establishments. Similarly, the punched-card tabulating system developed to enable the US govern- ment to cope with its 1890 census data gained wide commercial use in the first half of the twentieth century, and was in fact the origin of IBM.

Also beginning in the nineteenth century and reaching maturity in the 1920s and 1930s was a separate tradition of analog computing. Engineers built simplified physical models of their problems and measured the values they needed to calcu- late. Analog computers were used extensively and effectively in the design of elec- tric power networks, dams, and aircraft.

Although the calculating technologies available through the 1930s served busi- ness and scientific users well, during World War II they were not up to the de- mands of the military, which wanted to break codes, prepare firing tables for new guns, and design atomic weapons. The old technologies had three shortcomings: they were too slow in doing their calculations, they required human intervention in the course of a computation, and many of the most advanced calculating systems were special-purpose rather than general-purpose devices.

Because of the exigencies of the war, the military was willing to pay whatever it would take to develop the kinds of calculating machines it needed. Millions of dol- lars were spent, resulting in the production of the first electronic, stored-program

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computers—although, ironically, none of them was completed in time for war work. The military and scientific research value of these computers was nevertheless appreciated, and by the time of the Korean War a small number had been built and placed in operation in military facilities, atomic energy laboratories, aerospace man- ufacturers, and research universities.

Although the computer had been developed for number crunching, several groups recognized its potential as a data-processing and accounting machine. The developers of the most important wartime computer, the ENIAC, left their univer- sity posts to start a business building computers for the scientific and business mar- kets. Other electrical manufacturers and business-machine companies, including IBM, also turned to this enterprise. The computer makers found a ready market in government agencies, insurance companies, and large manufacturers.

The basic functional specifications of the computer were set out in a report writ- ten by John von Neumann in 1945, and these specifications are still largely fol- lowed today. However, decades of continuous innovation have followed the original conception. These innovations are of two types. One is the improvement in components, leading to faster processing speed, greater information-storage ca- pacity, improved price/performance, better reliability, less required maintenance, and the like: today’s computers are literally millions of times better than the first computers on almost all measures of this kind. These innovations were made pre- dominantly by the firms that manufactured computers.

The second type of innovation was in the mode of operation, but here the agent for change was most often the academic sector, backed by government financing. In most cases, these innovations became a standard part of computing only through their refinement and incorporation into standard products by the computer manu- facturers. There are five notable examples of this kind of innovation: high-level pro- gramming languages, real-time computing, time-sharing, networking, and graphically oriented human-computer interfaces.

While the basic structure of the computer remained unchanged, these new components and modes of operation revolutionized our human experiences with computers. Elements that we take for granted today—such as having a computer on our own desk, equipped with a mouse, monitor, and disk drive—were not even conceivable until the 1970s. At that time, most computers cost hundreds of thousands, or even millions, of dollars and filled a large room. Users would sel- dom touch or even see the computer itself. Instead, they would bring a stack of punched cards representing their program to an authorized computer operator and return hours or days later to pick up a printout of their results. As the main- frame became more refined, the punched cards were replaced by remote termi- nals, and response time from the computer became almost immediate—but still only the privileged few had access to the computer. All of this changed with the

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development of the personal computer and the growth of the Internet. The mainframe has not died out, as many have predicted, but computing is now available to the masses.

As computer technology became increasingly less expensive and more portable, new and previously unanticipated uses for computers were discovered—or in- vented. Today, for example, the digital devices that many of us carry in our brief- cases, backpacks, purses, or pockets serve simultaneously as portable computers, communications tools, entertainment platforms, digital cameras, monitoring de- vices, and conduits to increasingly omnipresent social networks. The history of the computer has become inextricably intertwined with the history of communications and mass media, as our discussion of the personal computer and the Internet clearly illustrates. But it is important to keep in mind that even in cutting-edge companies like Facebook and Google, multiple forms and meaning of the computer continue to coexist, from the massive mainframes and server farms that store and analyze data to the personal computers used by programmers to develop software to the mobile devices and applications with which users create and consume content. As the computer itself continues to evolve and acquire new meanings, so does our un- derstanding of its relevant history. But it is important to remember that these new understandings do not refute or supersede these earlier histories but rather extend, deepen, and make them even more relevant.

WE HAVE ORGANIZED the book in four parts. The first covers the way com- puting was handled before the arrival of electronic computers. The next two parts describe the mainframe computer era, roughly from 1945 to 1980, with one part devoted to the computer’s creation and the other to its evolution. The final part discusses the origins of personal computing and the Internet.

Part One, on the early history of computing, includes three chapters. Chapter 1 discusses manual information processing and early technologies. People often sup- pose that information processing is a twentieth-century phenomenon; this is not so, and the first chapter shows that sophisticated information processing could be done with or without machines—slower in the latter case, but equally well. Chap- ter 2 describes the origins of office machinery and the business-machine industry. To understand the post–World War II computer industry, we need to realize that its leading firms—including IBM—were established as business-machine manufac- turers in the last decades of the nineteenth century and were major innovators be- tween the two world wars. Chapter 3 describes Charles Babbage’s failed attempt to build a calculating engine in the 1830s and its realization by Harvard University and IBM a century later. We also briefly discuss the theoretical developments asso- ciated with Alan Turing.

Part Two of the book describes the development of the electronic computer, from its invention during World War II up to the establishment of IBM as the

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dominant mainframe computer manufacturer in the mid-1960s. Chapter 4 covers the development of the ENIAC at the University of Pennsylvania during the war and its successor, the EDVAC, which was the blueprint for almost all subsequent computers up to the present day. Chapter 5 describes the early development of the computer industry, which transformed the computer from a scientific instrument for mathematical computation into a machine for business data processing. In Chapter 6 we examine the development of the mainframe computer industry, fo- cusing on the IBM System/360 range of computers, which created the first stable industry standard and established IBM’s dominance.

Part Three presents a selective history of some key computer innovations in the quarter-century between the invention of the computer at the end of the war and the development of the first personal computers. Chapter 7 is a study of one of the key technologies of computing, real time. We examine this subject in the context of commonly experienced applications, such as airline reservations, banking and ATMs, and supermarket bar codes. Chapter 8 describes the development of soft- ware technology, the professionalization of programming, and the emergence of a software industry. Chapter 9 covers the development of some of the key features of the computing environment at the end of the 1960s: time-sharing, minicomputers, and microelectronics. The purpose of the chapter is, in part, to redress the com- monly held notion that the computer transformed from the mainframe to the per- sonal computer in one giant leap.

Part Four gives a history of the developments of the last forty years that brought the computer to most people’s desktops and into their personal lives. Chapter 10 describes the development of the microcomputer from the first hobby computers in the mid-1970s up to its transformation into the familiar personal computer by the end of the decade. Chapter 11’s focus is on the personal-computer environment of the 1980s, when the key innovations were user-friendliness and the delivery of “content,” by means of CD-ROM storage and consumer networks. This decade was characterized by the extraordinary rise of Microsoft and the other personal- computer software companies. The book concludes with a discussion of the Inter- net. The focus is on the World Wide Web, its precedents in the information sciences, and its ever-evolving commercial and social applications.

We have included notes at the end of the book. These indicate the exact sources of our quotations and lead the interested reader to some of the major literature on the history of computing.

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Part One

BEFORE THE COMPUTER

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1

WHEN COMPUTERS WERE PEOPLE

THE WORD computer is a misleading name for the ubiquitous machine that sits on our desks. If we go back to the Victorian period, or even to the World War II era, the word meant an occupation, defined in the Oxford English Dictionary as “one who computes; a calculator, reckoner; specifically a person employed to make calculations in an observatory, in surveying, etc.”

In fact, although the modern computer can work with numbers, its main use is for storing and manipulating information—that is, for doing the kinds of jobs per- formed by a clerk, defined in the Oxford English Dictionary as “one employed in a subordinate position in a public or private office, shop, warehouse, etc., to make written entries, keep accounts, make fair copies of documents, do the mechanical work of correspondence and similar ‘clerkly’ work.”

The electronic computer can be said to combine the roles of the human com- puter and the human clerk.

LOGARITHMS AND MATHEMATICAL TABLES

The first attempt to organize information processing on a large scale using human computers was for the production of mathematical tables, such as logarithmic and trigonometric tables. Logarithmic tables revolutionized mathematical computation in the sixteenth and seventeenth centuries by enabling time-consuming arithmetic operations, such as multiplication and division and the extraction of roots, to be performed using only the simple operations of addition and subtraction. Trigono- metric tables enabled a similar speeding up of calculations of angles and areas in connection with surveying and astronomy. However, logarithmic and trigonomet- ric tables were merely the best-known general-purpose tables. By the late eighteenth

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century, specialized tables were being produced for several different occupations: navigational tables for mariners, star tables for astronomers, life insurance tables for actuaries, civil engineering tables for architects, and so on. All these tables were produced by human computers, without any mechanical aid.

For a maritime nation such as Great Britain, and later the United States, the timely production of reliable navigation tables free of error was of major economic importance. In 1766 the British government sanctioned the astronomer royal, Nevil Maskelyne, to produce each year a set of navigational tables to be known as the Nautical Almanac. This was the first permanent table-making project to be es- tablished in the world. Often known as the Seaman’s Bible, the Nautical Almanac dramatically improved navigational accuracy. It has been published without a break every year since 1766.

The Nautical Almanac was not computed directly by the Royal Observatory, but by a number of freelance human computers dotted around Great Britain. The calculations were performed twice, independently, by two computers and checked by a third “comparator.” Many of these human computers were retired clerks or clergymen with a facility for figures and a reputation for reliability who worked from home. We know almost nothing of these anonymous drudges. Probably the only one to escape oblivion was the Reverend Malachy Hitchins, an eighteenth- century Cornish clergyman who was a computer and comparator for the Nautical Almanac for a period of forty years. A lifetime of computational dedication earned him a place in the Dictionary of National Biography. When Maskelyne died in 1811—Hitchins had died two years previously—the Nautical Almanac “fell on evil days for about 20 years, and even became notorious for its errors.”

CHARLES BABBAGE AND TABLE MAKING

During this period Charles Babbage became interested in the problem of table making and the elimination of errors in tables. Born in 1791, the son of a wealthy London banker, Babbage spent his childhood in Totnes, Devon, a country town in the west of England. He experienced indifferent schooling but succeeded in teach- ing himself mathematics to a considerable level. He went to Trinity College, Cam- bridge University, in 1810, where he studied mathematics. Cambridge was the leading English university for mathematics, and Babbage was dismayed to discover that he already knew more than his tutors. Realizing that Cambridge (and En- gland) had become a mathematical backwater compared to continental Europe, Babbage and two fellow students organized the Analytical Society, which suc- ceeded in making major reforms of mathematics in Cambridge and eventually the whole of England. Even as a young man, Babbage was a talented propagandist.

Babbage left Cambridge in 1814, married, and settled in Regency London to lead the life of a gentleman philosopher. His researches were mainly mathematical,

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and in 1816 his achievements were recognized by his election to the Royal Society, the leading scientific organization in Britain. He was then twenty-five—an enfant terrible with a growing scientific reputation.

In 1819 Babbage made the first of several visits to Paris, where he met a number of the leading members of the French Scientific Academy, such as the mathemati- cians Pierre-Simon Laplace and Joseph Fourier, with whom he formed lasting friendships. It was probably during this visit that Babbage learned of the great French table-making project organized by Baron Gaspard de Prony. This project would show Babbage a vision that would determine the future course of his life.

De Prony began the project in 1790, shortly after the French Revolution. The new government planned to reform many of France’s ancient institutions and, in particular, to establish a fair system of property taxation. To achieve this, up-to-date maps of France were needed. De Prony was charged with this task and was ap- pointed head of the Bureau du Cadastre, the French ordinance survey office. His task was made more complex by the fact that the government had simultaneously decided to reform the old imperial system of weights and measures by introducing the new rational metric system. This created within the bureau the job of making a complete new set of decimal tables, to be known as the tables du cadastre. It was by far the largest table-making project the world had ever known, and de Prony decided to organize it much as one would organize a factory.

De Prony took as his starting point the most famous economics text of his day, Adam Smith’s Wealth of Nations, published in 1776. It was Smith who first advo- cated the principle of division of labor, which he illustrated by means of a pin- making factory. In this famous example, Smith explained how the making of a pin could be divided into several distinct operations: cutting the short lengths of wire to make the pins, forming the pin head, sharpening the points, polishing the pins, packing them, and so on. If a worker specialized in a single operation, the output would be vastly greater than if a single worker performed all the operations that went into making a pin. De Prony “conceived all of a sudden the idea of applying the same method to the immense work with which I had been burdened, and to manufacture logarithms as one manufactures pins.”

De Prony organized his table-making “factory” into three sections. The first section consisted of half a dozen eminent mathematicians, including Adrien-Marie Legendre and Lazare Carnot, who decided on the mathematical formulas to be used in the calcu- lations. Beneath them was another small section—a kind of middle management— that, given the mathematical formulas to be used, organized the computations and compiled the results ready for printing. Finally, the third and largest section, which consisted of sixty to eighty human computers, did the actual computation. The com- puters used the “method of differences,” which required only the two basic operations of addition and subtraction, and not the more demanding operations of multiplica- tion and division. Hence the computers were not, and did not need to be, educated

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beyond basic numeracy and literacy. In fact, most of them were hairdressers who had lost their jobs because “one of the most hated symbols of the ancient regime was the hairstyles of the aristocracy.”

Although the Bureau was producing mathematical tables, the operation was not itself mathematical. It was fundamentally the application of an organizational tech- nology, probably for the first time outside a manufacturing or military context, to the production of information. Its like would not be seen again for another forty years.

The whole project lasted about a decade, and by 1801 the tables existed in man- uscript form all ready for printing. Unfortunately, for the next several decades, France was wracked by one financial and political crisis after another, so that the large sum of money needed to print the tables was never found. Hence, when Bab- bage learned of the project in 1819, all there was to show of it was the manuscript tables in the library of the French Scientific Academy.

In 1820, back in England, Babbage gained some firsthand experience of table making while preparing a set of star tables for the Astronomical Society, a scientific society that he and a group of like-minded amateur scientists had established the same year. Babbage and his friend John Herschel were supervising the construction of the star tables, which were being computed in the manner of the Nautical Al- manac by freelance computers. Babbage’s and Herschel’s roles were to check the ac- curacy of the calculations and to supervise the compilation and printing of the results. Babbage complained about the difficulty of table making, finding it error- prone and tedious; and if he found it tedious just supervising the table making, so much the worse for those who did the actual computing.

Babbage’s unique role in nineteenth-century information processing was due to the fact that he was in equal measure a mathematician and an economist. The mathematician in him recognized the need for reliable tables and knew how to make them, but it was the economist in him that saw the significance of de Prony’s organizational technology and had the ability to carry the idea further.

De Prony had devised his table-making operation using the principles of mass production at a time when factory organization involved manual labor using very simple tools. But in the thirty years since de Prony’s project, best practice in facto- ries had itself moved on, and a new age of mass-production machinery was begin- ning to dawn. The laborers in Adam Smith’s pin-making factory would soon be replaced by a pin-making machine. Babbage decided that rather than emulate de Prony’s labor-intensive and expensive manual table-making organization, he would ride the wave of the emerging mass-production technology and invent a ma- chine for making tables.

Babbage called his machine a Difference Engine because it would use the same method of differences that de Prony and others used in table making. Babbage knew, however, that most errors in tables came not from calculating them but from

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printing them, so he designed his engine to set the type ready for printing as well. Conceptually, the Difference Engine was very simple: it consisted of a set of adding mechanisms to do the calculations and a printing part.

Babbage applied his considerable skills as a publicist to promote the idea of the Difference Engine. He began his campaign by writing an open letter to the presi- dent of the Royal Society, Sir Humphrey Davy, in 1822, proposing that the gov- ernment finance him to build the engine. Babbage argued that high-quality tables were essential for a maritime and industrial nation, and that his Difference Engine would be far cheaper than the nearly one hundred overseers and human computers in de Prony’s table-making project. He had the letter printed at his own expense and ensured that it got into the hands of people of influence. As a result, in 1823 he obtained government funding of £1,500 to build the Difference Engine, with the understanding that more money would be provided if necessary.

Babbage managed to rally much of the scientific community to support his proj- ect. His boosters invariably argued that the merit of his Difference Engine was that it would eliminate the possibility of errors in tables “through the unerring certainty of mechanism.” It was also darkly hinted that the errors in the Nautical Almanac and other tables might “render the navigator liable to be led into difficulties, if not danger.” Babbage’s friend Herschel went a step further, writing: “An undetected er- ror in a logarithmic table is like a sunken rock at sea yet undiscovered, upon which it is impossible to say what wrecks may have taken place.” Gradually the danger of errors in tables grew into lurid tales that “navigational tables were full of errors which continually led to ships being wrecked.” Historians have found no evidence for this claim, although reliable tables certainly helped Britain’s maritime activity run smoothly.

Unfortunately, the engineering was more complicated than the conceptualiza- tion. Babbage completely underestimated the financial and technical resources he would need to build his engine. He was at the cutting edge of production technol- ogy, for although relatively crude machines such as steam engines and power looms were in widespread use, sophisticated devices such as pin-making machines were still a novelty. By the 1850s such machinery would be commonplace, and there would exist a mechanical-engineering infrastructure that made building them rela- tively easy. While building the Difference Engine in the 1820s was not in any sense impossible, Babbage was paying the price of being a first mover; it was rather like building the first computers in the mid-1940s: difficult and extremely expensive.

Babbage was now battling on two fronts: first, designing the Difference Engine and, second, developing the technology to build it. Although the Difference En- gine was conceptually simple, its design was mechanically complex. In the London Science Museum today, one can see evidence of this complexity in hundreds of Babbage’s machine drawings for the engines and in thousands of pages of his note- books. During the 1820s, Babbage scoured the factories of Europe seeking gadgets

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and technology that he could use in the Difference Engine. Not many of his dis- coveries found their way into the Difference Engine, but he succeeded in turning himself into the most knowledgeable economist of manufacturing of his day. In 1832 he published his most important book, an economics classic titled Economy of Machinery and Manufactures, which ran to four editions and was translated into five languages. In the history of economics, Babbage is a seminal figure who con- nects Adam Smith’s Wealth of Nations to the Scientific Management movement, founded in America by Frederick Winslow Taylor in the 1880s.

The government continued to advance Babbage money during the 1820s and early 1830s, eventually totaling £17,000; and Babbage claimed to have spent much the same again from his own pocket. These would be very large sums in to- day’s money. By 1833, Babbage had produced a beautifully engineered prototype Difference Engine that was too small for real table making and lacked a printing unit, but showed beyond any question the feasibility of his concept. (It is still on permanent exhibit in the London Science Museum, and it works as perfectly to- day as it did then.)

To develop a full-scale machine Babbage needed even more money, which he requested in a letter in 1834 to the prime minister, the Duke of Wellington. Un- fortunately, at that time, Babbage had an idea of such stunning originality that he just could not keep quiet about it: a new kind of engine that would do all the Dif- ference Engine could do but much more—it would be capable of performing any calculation that a human could specify for it. This machine he called the Analyti- cal Engine. In almost all important respects, it had the same logical organization as the modern electronic computer. In his letter to the Duke of Wellington, Bab- bage hinted that instead of completing the Difference Engine he should be al- lowed to build the Analytical Engine. Raising the specter of the Analytical Engine was the most spectacular political misjudgment of Babbage’s career; it fatally un- dermined the government’s confidence in his project, and he never obtained an- other penny. In fact, by this time, Babbage was so thoroughly immersed in his calculating-engine project that he had completely lost sight of the original objec- tive: to make tables. The engines had become an end in themselves, as we shall see in Chapter 3.