Bernard Cohen
Abstract. Howard Aiken, one of the pioneers who introduced the computer age, earned his place in the historical record by several different sets of achievements. One was his design and completion of four giant calculators (or computers) at the dawn and during the first stages of the computer age, another his pioneering program in what we know today as computer science. He also was one of the very first explorers of the application of the new machines to business purposes – problems of the life insurance industry and computer billing in the utilities industries. He also contributed to the computer age in sponsoring new areas of application for computers, including machine translation of foreign languages, the use of the new machines in textual and historical analysis, and the application of computers to economics. He was much in demand as a speaker in America and in Europe, and he constantly urged the introduction of the computer into new areas of research and action. His contributions to the new age also include two symposiums he organized (in 1947 and 1949) to bring together those who were pioneering the designs and construction of new computers or planning new
applications.
1—
Aiken's Background
Aiken's primary claim to a notable place in history is usually said to be his first machine, converted from his specifications into engineering reality by IBM engineers. This machine, known as Mark I (or the Harvard Mark I), and originally named the IBM ASCC, gave the world of scientists and engineers a visible proof that a complex machine could solve complicated mathematical problems by being programmed to execute a series of controlled operations in a predetermined sequence – and do so without error.
1 This talk is based on the writer's recently published book, Howard Aiken, Portrait of a Computer Pioneer (Cambridge: MIT Press, 1999); also a companion volume of essays, edited by the writer together with Gregory M. Welch and Robert V. D.
Campbell, "Makin 'Numbers ": Howard Aiken and the Computer (Cambridge: MIT Press, 1999).
A strong man in both his quality of mind and his physical being, Aiken had all the strengths and weaknesses of successful pioneers. He forced Harvard, an essentially humanistic university, into adopting a leading role in the new art and science of computing. Some of his visions of the future so outran the course of events that his predictions were often not validated until decades later. He was strongly opposed to the new concept of the stored program, primarily because he feared that the mixing of program or instructions with data in the same store would jeopardize the integrity of the program, and he had a basic dislike of binary number systems.
Aiken's early life set him in a personality mold which affected his relations with students and colleagues and which determined his character. A daring and bold pioneer, he was self-willed, and combative. Aiken was a giant of a man–in his physical stature, his force of will, his originality of mind, and his achievement. Standing erect at six feet and some inches tall, he towered over most of his students and colleagues. Graced by nature with a huge dome of a head, he had piercing eyes crowned with huge beetling and somewhat satanic eyebrows.
Aiken related to people in extremes. When he met you, you were almost at once graded, placed at the top of his scale or the bottom–there was never a middle ground. On a scale from one to ten, Aiken would rate you as a zero or an eleven. People reacted to Aiken in the same way. His students and associates either admired him and established a friendly relationship or found him to be "impossible." Friends and colleagues and former students on the "plus" side remained loyal and devoted for the rest of their lives and Aiken himself cherished long-term relations. Those on the "minus" side tend to remember only those occasions when he was intransigent and difficult.
Howard Hathaway Aiken was born in Hoboken, New Jersey, in 1901 and was educated in the public school system of Indianapolis. Throughout his four years of high school, he held a full-time job, working a twelve-hour shift at night, in order to support his mother and grandmother who had no other source of income. On
graduation, he enrolled as an undergraduate in the University of Wisconsin, where he continued to work at nights in order to support himself and his family. During an oral-history interview which Henry Tropp and I conducted with Aiken shortly before his death, on 24 February 1973, he explained that Wisconsin had adopted
"the eight hour day" and so he "had to work from four to midnight on that job" which "was much easier" than the twelve-hour shift at Indianapolis.
Aiken graduated from the University with a bachelor's degree in electrical engineering. After a decade as a successful electrical engineer, he found himself elevated to a managerial position without contact with daily problems of engineering practice. He resigned his business post and decided to go back to the university for higher training in the sciences. His first choice was the University of Chicago, but he didn't like Chicago and transferred to Harvard, where he entered the graduate program in physics in 1931. At that time, Aiken was thirty years of age, much older than his fellow graduate students.
At Harvard Aiken became a member of a small group of faculty members and students associated with the Physics Department and known by the subject name of "communication engineering." Basically, the members of this group were concerned with the physics of electromagnetic waves (their transmission, reflection,
reception, and so on), the study of radio transmission problems, and the physics of the operating units of radio transmission. Thus, one member of the group investigated the way in which radio waves bounce off the ionospheric layer, another the design of antennas and antenna theory generally. The head of the group, the person with whom Aiken did his research, E. L. Chaffee, was primarily interested in the physics of vacuum tubes.
2—
Computing Machines
As was the custom of those days, Aiken was assigned a problem for his doctoral research and eventual
dissertation. His problem was the conductivity of space charge, "a field where one runs into [partial] differential equations in cylindrical co-ordinates . . . in nonlinear terms, of course." Before long his thesis research came to consist primarily of "solving nonlinear [differential] equations."
The only methods then available for numerical solutions of problems like his made use of electromechanical desk calculators, of about the size of today's cash registers, so that calculations like those he needed were
"extremely time consuming." It became apparent–"at once," according to Aiken–that the labor of calculating
"could be mechanized and programmed and that an individual didn't have to do this." He was also aware that a computing machine would also be of great use in solving pressing problems in many sciences and in
engineering and even in the social sciences.
By April 1937, he had progressed sufficiently far in his general thinking and design to be ready to seek support from industry. In preparation, Aiken drew up a proposal stating the need for such a machine, together with the principal features of its mode of operation and its general method of solving problems. His philosophy was later expressed in a student's assignment, drawn up for one of his Harvard classes in computer science. "The 'design' of a computing machine," the students were informed, "is understood to consist in the outlining of its general specifications and the carrying through of a rational determination of its functions, but does not include the actual engineering design of component units."
In this clear statement, as was often the case for Aiken, the primary concerns were the logic of the machine, the mathematical operations, and the general architecture, while the actual technological specifications or the choice of components was secondary. To judge from all the information available, Aiken's design would not have specified what particular components (nor even what types of components – mechanical,
electromechanical, electronic) would be used, nor how the various components of the machine would be linked.
He would have specified the need for performing certain types of mathematical operations and a means of programming them so that they would be performed in a certain predetermined sequence. He also would have indicated the need for storing certain tables of numerical data. These specifications would have been definite but not necessarily confined to any particular type of functioning elements. Thus the design would apply equally to a machine that would be constructed of mechanical, electromechanical, or electronic components, or any combination of them.
Once Aiken had completed the general design of his proposed machine, his next step was to find some company willing to build it. During the course of our interview, Aiken explained that because of the size and complexity of his proposed machine, only a large manufacturer of calculators or business machines could possibly have been induced to produce it. Accordingly, he turned first to America's foremost manufacturer of calculators, the Monroe Calculating Machine Company. Armed with his document of specifications, Aiken obtained an
interview, which took place on 22 April 1937, with George C. Chase, a distinguished inventor in the calculator field who was then Monroe's director of research.
Chase later reported how Aiken outlined his conception of the machine and "explained what it could
accomplish in the fields of mathematics, science, and sociology." Aiken told Chase that "certain branches of science had reached a barrier that could not be passed until means could be found to solve mathematical problems too large to be undertaken with the then-known computing equipment." Although Aiken referred to
"the construction of an electromechanical machine," he had not as yet specified what kind of actual components were to be used. Chase was quite emphatic on this point. The "plan he outlined," Chase wrote, "was not
restricted to any specific type of mechanism.'' Rather, his design "embraced a broad coordination of components that could be resolved by various constructive mediums."
Aiken's attempt to elicit the support of Monroe came up rather early during the interview, when I pressed him to explain why he had chosen to build Mark I out of electromechanical parts. After all, his thesis was on vacuum tubes, on space charge, and his own graduate specialty was the field of electronics. Why, I wanted to know, did he even consider electromechanical systems rather than electronic systems? Why had he not contemplated using vacuum tubes? I must confess that I expected Aiken to frame his reply in terms of his great often-expressed ideal: reliability! I will even confess that I asked the question less as a means of obtaining information than as an opportunity to record on tape – direct from Aiken's mouth – his thundering condemnation of unreliable vacuum tubes and his preference for slower and more reliable relays.
It was only much later that, thanks primarily to a little tutorial given to me by Bob Campbell and to the
insightful comments of Maurice Wilkes, I came to understand that Aiken's study of the physics of vacuum tubes was only indirectly related to the use of vacuum tubes in designing electronic circuits. In fact, in a statement written by Aiken toward the end of the war, in 1945, he reviewed the goals of education in the Cruft
Laboratory, where the "plan for instruction" had been designed around "basic scientific material of
communication engineering," together with "much of the allied branches of science." There was "no attempt to apply this material to specific engineering problems." Instead, the program had been directed exclusively to ''the elucidation of fundamental scientific principles." For the purposes of computation, however, what was needed was not the scientific principles underlying circuitry, not a knowledge of the physics of space charge, but rather some experience in the design of high speed pulse circuitry. In this latter area Aiken had little or no experience.
In a talk given in Sweden and in Germany in 1956, Aiken recalled that, in his undergraduate days at the
University of Wisconsin, in his senior year, when he was a student of electrical engineering, "there was offered for the first time a course called 'thermionic vacuum tubes.' " He didn't explore this new field, however, because his professors advised him that he "would do far better" if he "took the course in transformer design rather than this new and untried subject."
Once started, Aiken continued his recollections of Chase. He was "Chief Engineer at Monroe," he said, "and a very, very, scholarly gentleman. He took an almost immediate interest, and we kept up an association for quite a few years thereafter. He wanted, in the worst way, to build Mark I. He would supply me with the parts and we would collaborate and do it together, that's what he wanted to do."
Chase was enthusiastic about Aiken's project. According to Aiken, Chase "went to his management at Monroe and he did everything within his power to convince them that they should go ahead with this machine because, although it would be an expensive development." Chase had the vision and foresight to recognize that the proposed machine "would be invaluable in the company's business in later years." But, although "Chase could see this," his "management, however, after some months of discussion turned him down completely."
Aiken's remarks about his not having been wed to a single type of components for his dream machine was very revealing, but I was not completely satisfied by Aiken's presentation. I wanted him to discuss what he
remembered about the relative advantages and disadvantages of mechanical systems, electromagnetic devices, and vacuum tube circuits. Accordingly, a little later in the interview, I returned to the subject of why Aiken had chosen to have his machine built of electromechanical components such as relays–why he had not made use of vacuum tubes. This time I stressed the fact that this choice of relays had always seemed astonishing to me in view of the fact that Aiken had been a student at Harvard of E. L. Chaffee, under whose direction he had written his doctoral dissertation; Chaffee's specialty was vacuum tubes and vacuum tube circuits. To be specific, I asked whether at one time there hadn't been some thought given to having quenching circuits in that first machine, using vacuum tubes. Aiken replied, "Yes. But your question really is: since I had grown up in 'space charge' in a laboratory like Cruft [at Harvard], why wasn't Mark I an electronic device? Again the answer is money. It was going to take a lot of money. Thousands and thousands of parts!"
Then he explained: "It was clear that this thing could be done with electronic parts, too, using the techniques of the digital counters that had been made with vacuum tubes, just a few years before I started, for counting cosmic rays." And then he concluded with the following dramatic assertion: "But what it comes down to is this:
if Monroe had decided to pay the bill, this thing would have been made out of mechanical parts. If RCA had been interested, it might have been electronic. And it was made out of tabulating machine parts because IBM was willing to pay the bill."
Clearly, at this time, Aiken was not wedded to any particular technology, his top priority was not the choice of relays.
To most historians and computer specialists, it will seem just as astonishing as it was to us to learn that the choice of the kind of machine to be built was determined solely by financial considerations, by the willingness of one or another company to put up money for the machine. This disdain for the technological components was, I believe, a very significant part of Aiken's intellectual make-up. We shall see in a moment how this aspect of Aiken's system of values was a major factor in producing the eventual rift between him and IBM. Aiken never appreciated the degree to which the technology of IBM's product line may have made IBM the only company that at that time would have undertaken to build Aiken's machine. It is to be noted that when Eckert and Mauchly designed the ENIAC, constructed at the Moore School at the University of Pennsylvania, they did not base the machine on any company's off-the-shelf technology but rather developed new types of circuitry and design for the special purpose they had in mind.
3—
The Role of IBM
When Chase found that his company would not undertake to build Aiken's dream machine, he advised Aiken to try IBM. At IBM, Aiken's project won the immediate support of James Wares Bryce, IBM's chief engineer, then known affectionately within IBM as "the Father Engineer." Bryce was the holder of more than 400 patents, making an average of about one per month. In 1936, on the centenary of the U. S. Patent Office, Bryce was honored as one of the ten "greatest living inventors." Aiken's meetings with Bryce were the inaugural steps toward the construction of the Automatic Sequence Controlled Calculator.
As all histories of IBM make clear, no important decision was ever made at IBM without the explicit approval of IBM's president, Thomas J. Watson, senior. Watson was a powerful figure, a titan in his sphere and endowed with just as forceful a personality as Howard Aiken. Anyone who has read anything at all about these two figures will know that there would be an eventual collision, a terrible clash. And, after IBM built Aiken's dream machine, there was just such an inevitable conflict, also supported by Thomas J. Watson (Jr.), IBM's CEO.
Bryce wanted to be certain that Aiken would know about the different technologies used in IBM business machines, accumulators, sorters, and printers. And so Bryce arranged for Aiken to attend IBM's training school for technicians and then go out on the job of repair and maintenance of IBM machines. Only after Aiken had become familiar with the potentialities and limitations of IBM's product line did Bryce advance to the next step of getting the machine built.
At first it was envisaged that IBM would supply the parts and that, under Aiken's supervision and with some assistance from IBM engineers, the giant machine would be built at Harvard by mechanics in Harvard's own machine shops. Eventually, this proved to be impractical, and all of the work was done at IBM's facility in Endicott, New York. Bryce appointed Clair Lake to be the engineer in charge of the project. Francis ("Frank") Hamilton was the immediate supervisor, and Ben Durfee was actually in charge of day-to-day construction of the circuits and the design of the controls. These three engineers were skilled technicians of extremely high
At first it was envisaged that IBM would supply the parts and that, under Aiken's supervision and with some assistance from IBM engineers, the giant machine would be built at Harvard by mechanics in Harvard's own machine shops. Eventually, this proved to be impractical, and all of the work was done at IBM's facility in Endicott, New York. Bryce appointed Clair Lake to be the engineer in charge of the project. Francis ("Frank") Hamilton was the immediate supervisor, and Ben Durfee was actually in charge of day-to-day construction of the circuits and the design of the controls. These three engineers were skilled technicians of extremely high