Other articles in the series:
- The History of Relays
- The History of Electronic Computers
- The History of the Transistor
- The History of the Internet
So far, we have sequentially recalled each of the first three attempts to build a digital electronic computer: the Atanasoff-Berry Computer (ABC), conceived by John Atanasoff; the British Colossus project, led by Tommy Flowers; and the ENIAC, created at Moore School at the University of Pennsylvania. All these projects were essentially independent. Although John Mauchly, the driving force behind the ENIAC project, was aware of Atanasoff's work, the ENIAC design bore no resemblance to the ABC. If there existed any common ancestor of electronic computing devices, it would be the humble Wina-Williams counter, the first device to use vacuum tubes for digital storage, allowing Atanasoff, Flowers, and Mauchly to embark on the path of creating electronic computers.
However, only one of these three machines played its part in the subsequent events. The ABC never performed any useful work, and, for the most part, the few who knew about it forgot it. The two military machines proved capable of outpacing any other existing computers in pure performance; however, the Colossus remained secret even after the victory over Germany and Japan. Only the ENIAC became widely known, and thus it became the standard bearer for electronic computation. Now anyone wanting to create a computing device based on vacuum tubes could point to the success of the Moore School as validation. The deep skepticism of the engineering community that had met all such projects before 1945 disappeared; skeptics either changed their minds or fell silent.
Report on EDVAC
The document released in 1945, based on the experiences gained from developing and using the ENIAC, set the tone for the future of computing in the world after World War II. It was titled "First Draft of a Report on the EDVAC" [Electronic Discrete Variable Automatic Computer], and it provided a blueprint for the architecture of the first computers, programmable in the modern sense ā that is, executing commands fetched from high-speed memory. Although the exact origins of the ideas listed in it remain a topic of debate, it was signed by the mathematician (born John von Neumann). Characteristic of a mathematician's mind, the document also made the first attempt to abstract the workings of a computer from the specifications of specific machines; it sought to separate the essence of computer architecture from its various possible and random manifestations.
John von Neumann, born in Hungary, arrived at ENIAC via Princeton (New Jersey) and Los Alamos (New Mexico). In 1929, as an accomplished young mathematician with notable contributions to set theory, quantum mechanics, and game theory, he left Europe to take a position at Princeton University. Four years later, the nearby Institute for Advanced Study (IAS) offered him a lifelong appointment. Due to the rise of Nazism in Europe, von Neumann eagerly seized the chance to remain indefinitely on the other side of the Atlantic ā and became, in retrospect, one of the first Jewish intellectual refugees from Hitler's Europe. After the war, he lamented: "My feelings toward Europe are the opposite of nostalgia, as every familiar corner reminds me of a vanished world and of ruins that bring no consolation," recalling "my complete disillusionment with humaneness from 1933 to 1938."
Disillusioned by the lost multinational Europe of his youth, von Neumann directed all his intellect towards aiding the military machinery of the country that had adopted him. Over the next five years, he traveled across the country, offering advice and consulting on a wide range of new weapon projects, while somehow managing to co-author a prolific book on game theory. His most secret and critical work as a consultant was his role in the Manhattan Projectāan attempt to create the atomic bombāwhose research team was located in Los Alamos, New Mexico. Robert Oppenheimer recruited him in the summer of 1943 to assist with the project's mathematical modeling, and his calculations convinced the other team members to move towards a bomb with an inward-directed explosion. Such an explosion, facilitated by an explosive compressing the fissile material inward, was supposed to achieve a self-sustaining chain reaction. As a result, an enormous amount of calculations were required to achieve the perfect inward-directed spherical explosion with the necessary pressureāany mistake would lead to the interruption of the chain reaction and the bomb's failure.
Von Neumann at Work in Los Alamos
In Los Alamos, a group of twenty computing individuals was equipped with desk calculators, but they couldn't handle the computational load. The scientists provided them with IBM equipment for working with punch cards, yet they still fell behind. They requested upgraded equipment from IBM, received it in 1944, but still struggled to keep up.
By that time, von Neumann had added another set of places to visit to his regular cruise around the country: he was visiting every possible site of computer equipment that could be useful in Los Alamos. He wrote a letter to Warren Weaver, head of the applied mathematics department at the National Defense Research Committee (NDRC), and received some good leads. He visited Harvard to see the Mark I, but it was already fully occupied with work for the Navy. He talked with George Stibitz and considered ordering a Bell relay computer for Los Alamos, but he abandoned the idea upon learning how long it would take. He visited a group from Columbia University that had combined several IBM computers into a larger automated system under the management of Wallace Eckert, but there were no noticeable improvements compared to the IBM computers already in Los Alamos.
However, Weaver did not include one project on the list he gave to von Neumann: ENIAC. He definitely knew about it: in his position as director of applied mathematics, he was responsible for tracking the progress of all computing projects in the country. Weaver and the NDRC could certainly have doubts about the viability and timeline of ENIAC, but it is quite surprising that he didnāt even mention its existence.
Whatever the reason for this, von Neumann learned about ENIAC only due to a chance encounter on a train platform. This story was told by Herman Goldstein, an intermediary from the Moore School's test laboratory where ENIAC was being built. Goldstein ran into von Neumann at the Aberdeen train station in June 1944 ā von Neumann was leaving from one of his consultations, which he, as a member of the scientific advisory committee, was giving at the Aberdeen Ballistic Research Laboratory. Goldstein was aware of von Neumann's reputation as a great man, and he struck up a conversation with him. Wanting to make an impression, he couldn't help but mention the new and interesting project developing in Philadelphia. Von Neumann's demeanor instantly shifted from that of a benign colleague to that of a stern controller, and he bombarded Goldstein with questions related to the details of the new computer. He found a new intriguing source of potential computational power for Los Alamos.
Von Neumann first visited Presper Eckert, John Mauchly, and other members of the ENIAC team in September 1944. He immediately fell in love with this project and added another item to his long list of organizations for consulting. Both parties benefited from this. It is easy to see why the potential of high-speed electronic computing attracted von Neumann. ENIAC, or a machine similar to it, had the ability to overcome all computational limitations that hindered the progress of the Manhattan Project and many other existing or potential projects (however, Say's Law, still in effect today, ensured that the emergence of computational capabilities would soon lead to an equal demand for them). For the Moore School, the blessing of such a recognized specialist as von Neumann marked the end of their skeptical approach. Moreover, given his lively mind and rich experience working throughout the country, he was unmatched in both the breadth and depth of knowledge in the field of automatic computation.
This is how von Neumann became involved in Eckert and Mauchly's plan to create a successor to ENIAC. Together with Herman Goldstein and another mathematician from ENIAC, Arthur Burks, they began to draft the parameters for the second generation of electronic computers, and it was this group's ideas that von Neumann summarized in his report "the first draft." The new machine was to be more powerful, have smoother contours, and, most importantly, overcome the biggest barrier to using ENIAC ā the hours-long setup for each new task, during which this mighty and extremely expensive computing machine would simply sit idle. Developers of the latest electromechanical machines, Harvard's Mark I and Bell's relay computer, avoided this issue by feeding instructions into the computer using punched paper tape ā the operator could prepare the tape while the machine solved other tasks. However, such a data input method would negate the speed advantage of electronics; no paper could feed data as quickly as ENIAC could accept it. (The "Colossus" worked with paper using photoelectric sensors, and each of its five computing modules absorbed data at a speed of 5000 characters per second, but this was only possible due to the maximum speed of the paper tape roll. Moving to a random point on the tape required a delay of 0.5 seconds for every 5000 lines).
The problem addressed in the 'first draft' involved moving the storage of instructions from an 'external recording medium' to 'memory'āthe word was used for the first time in relation to computer data storage (von Neumann specifically employed this and other biological terms in his work, as he was very interested in brain function and the processes occurring in neurons). This idea was later named 'program storage.' However, it immediately led to another problem that had previously baffled Atanasoff: the exorbitant cost of electronic tubes. The 'first draft' estimated that a computer capable of performing a wide range of computational tasks would require memory with 250,000 binary digits to store instructions and temporary data. Memory made from electronic tubes of that size would cost millions of dollars and would be completely unreliable.
The solution to the dilemma was proposed by Eckert, who was working in the early 1940s on radar research as part of a contract between the Moore School and MIT's 'Radar Lab,' the central research center for radar technologies in the USA. Specifically, Eckert was working on a radar system called the 'Moving Target Indicator' (MTI), which addressed the problem of 'ground clutter'āthe noise on the radar screen created by buildings, hills, and other stationary objects that complicated the operator's task of extracting important information about the size, location, and speed of moving aircraft.
In the MTI, the clutter problem was solved using a device called . It converted radar electrical impulses into sound waves and then sent these waves through a mercury tube in such a way that the sound arrived at the other end and was converted back into an electrical impulse at the moment the radar rescaned the same point in the sky (delay lines for sound propagation can also use other mediums, such as different liquids, solid crystals, and even air. According to some reports, the idea was conceived by Bell Labs physicist William Shockley, as mentioned later). Any signal coming from the radar at the same time as the signal through the tube was considered a signal from a stationary object and was eliminated.
Eckert realized that the sound pulses in the delay line could be considered binary numbers ā 1 indicates the presence of sound, and 0 indicates its absence. A single mercury tube could contain hundreds of such digits, each passing through the line several times per millisecond, meaning that the computer would have to wait a couple of hundred microseconds to access a digit. Meanwhile, access to sequential digits in the tube would be faster, as the digits were separated by only a few microseconds.
Mercury delay lines in the British EDSAC computer
After resolving the main issues in the computer's operation, von Neumann compiled the ideas of the entire group into a 101-page report titled "First Draft" in the spring of 1945 and distributed it among key figures of the second-generation EDVAC project. Soon, it infiltrated other circles as well. Mathematician Leslie Comrie, for example, took a copy home to Britain after visiting Moore School in 1946 and shared it with colleagues. The dissemination of the report caused outrage among Eckert and Mauchly for two reasons: first, most of the credit for the development was attributed to the author of the draft, von Neumann. Second, all the key ideas contained in the system were, in fact, published from the standpoint of the patent office, hindering their plans to commercialize the electronic computer.
The very foundation of Eckert and Mauchly's grievance, in turn, provoked indignation among mathematicians: von Neumann, Goldstein, and Burks. From their perspective, the report was an important new piece of knowledge that needed to be disseminated as widely as possible, according to the spirit of scientific progress. Moreover, the entire enterprise was funded by the government, meaning it was paid for by American taxpayers. They were repulsed by Eckert and Mauchly's mercenary attempt to profit from the war. Von Neumann wrote: "I would never have taken a position as a consultant at a university knowing I was advising a commercial group."
The paths of the factions diverged in 1946: Eckert and Mauchly established their own company based on what seemed to be a safer patent from the ENIAC technology. Initially, they named their enterprise Electronic Control Company, but the following year they renamed it to Eckert-Mauchly Computer Corporation. von Neumann returned to IAS to create a computer based on the EDVAC, joined by Goldstein and Burks. To prevent a recurrence of the situation with Eckert and Mauchly, they ensured that all intellectual property from the new project became public domain.
von Neumann in front of the IAS computer, built in 1951.
A digression dedicated to Alan Turing
Among those who saw the report on EDVAC through indirect means was British mathematician Alan Turing. Turing was not among the first scientists to create or conceive of an automatic computer, electronic or otherwise, and some authors have greatly exaggerated his role in the history of computing. However, we must give him credit as the first person to realize that computational machines could do more than just "calculate" by merely processing large sequences of numbers. His main idea was that the information processed by the human mind could be represented in numerical form, thus allowing any mental process to be transformed into a computation.
Alan Turing in 1951
At the end of 1945, Turing published his own report, mentioning von Neumann, titled "Proposal for an Electronic Calculator," intended for the British National Physical Laboratory (NPL). He did not delve deeply into the specific design details of the proposed electronic computer. His scheme reflected the reasoning of a logic specialist. No special hardware was intended for high-level functions, as they could be composed from low-level primitives; this would be an unsightly appendage to the beautiful symmetry of the machine. Turing also did not allocate any linear memory for the computer programādata and instructions could coexist in memory since they were just numbers. An instruction became an instruction only when it was interpreted as such (Turing's 1936 work "On Computable Numbers" had already explored the relationship between static data and dynamic instructions. He described what would later be called the "Turing machine" and demonstrated how it could be represented as a number and fed as input to a universal Turing machine capable of interpreting and executing any other Turing machine). Since Turing understood that numbers could represent any form of precisely defined information, in the list of tasks for this calculator, he included not only the construction of artillery tables and the solving of systems of linear equations but also solving puzzles and chess studies.
The Automatic Computing Engine (ACE) designed by Turing was never built in its original form. It was too slow and had to compete with more vigorous British computing projects for the best talents. The project stalled for several years, and then Turing lost interest in it. In 1950, NPL created the Pilot ACEāa smaller machine with a slightly different design; moreover, in the early 1950s, several other computer projects drew inspiration from the ACE architecture. However, it failed to expand its influence and quickly faded into obscurity.
However, all this does not diminish Turing's contributions; it simply helps to place him in the right context. The significance of his influence on the history of computers is not based on the computer designs of the 1950s, but rather on the theoretical foundation he laid for computer science, which emerged in the 1960s. His early work in mathematical logic, which explored the boundaries of computable and non-computable, became foundational texts for the new discipline.
The Gradual Revolution
With the spread of news about ENIAC and the EDVAC report, the Moore School became a pilgrimage site. Many visitors arrived to learn "at the feet of the masters", especially from the USA and Britain. To manage the influx of seekers, the school dean had to organize a summer school on automatic computing machines in 1946, operating by invitation. Lectures were given by luminaries such as Eckert, Mauchly, von Neumann, Burks, Goldstein, and Howard Aiken (the developer of Harvard's electromechanical computer Mark I).
Now almost everyone wanted to build machines according to the instructions from the EDVAC report (ironically, the first machine to run a stored program was ENIAC itself, which was modified in 1948 to use stored instructions. Only after this did it begin to function successfully in its new home, the Aberdeen Proving Ground). Even in the names of new computer projects created in the 1940s and 50s, the influence of ENIAC and EDVAC can be seen. Even aside from UNIVAC and BINAC (created at Eckert and Mauchly's new company) and ENIAC itself (completed at the Moore School after its founders had left), there remain AVIDAC, CSIRAC, EDSAC, FLAC, ILLIAC, JOHNNIAC, ORDVAC, SEAC, SILLIAC, SWAC, and WEIZAC. Many of them directly copied the freely published IAS design (with minor modifications), benefiting from von Neumann's openness regarding intellectual property.
However, the electronic revolution developed gradually, step by step changing the existing order. The first EDVAC-style machine appeared only in 1948, and it was merely a small project demonstrating the viability of the concept, the Manchester "baby", designed to confirm the feasibility of memory on (Most computing machines switched from mercury tubes to another type of memory, which also owes its origin to radar technology. Instead of tubes, however, it used an CRT screen. British engineer Frederick Williams was the first to figure out how to solve the stability problem of this memory, resulting in the storage devices being named after him). In 1949, four more machines were created: the full-size Manchester Mark I, EDSAC at the University of Cambridge, CSIRAC in Sydney (Australia), and the American BINAC ā although the latter never worked properly. A small but stable continued for the next five years.
Some authors have described the ENIAC as if it covered the past with a veil and instantly brought us into the era of electronic computing. Because of this, the real evidence became heavily distorted. "The emergence of the fully electronic ENIAC almost immediately rendered the Mark I obsolete (although it continued to operate successfully for another fifteen years)" ā wrote Katherine Fishman [Katherine Davis Fishman, The Computer Establishment (1982)]. This statement is so evidently self-contradictory that one might think Miss Fishman's left hand did not know what her right was doing. One could certainly attribute this to the notes of a simple journalist. However, we find that some true historians once again choose the Mark I as a punching bag, stating: "The Harvard Mark I was not only a technical dead end; it didn't really do anything very useful during its fifteen years of operation. It was used in a few military projects, and there the machine proved to be useful enough that the Navy ordered a few more computing machines for Aiken's lab" [Aspray and Campbell-Kelly]. Again, a clear contradiction.
In reality, relay computers had their own advantages, and they continued to operate alongside their electronic counterparts. Several new electromechanical computers were created after World War II, including in Japan in the early 1950s. Relay machines were easier to design, build, and maintain, and they required less electricity and cooling (to dissipate the vast amounts of heat generated by thousands of vacuum tubes). ENIAC used 150 kW of electricity, 20 of which was for cooling.
The American military continued to be the main consumer of computing power and did not neglect 'obsolete' electromechanical models. By the late 1940s, the army had four relay computers at its disposal, while the navy had five. At the Aberdeen Ballistic Research Laboratory, there was the largest concentration of computing power in the world, as ENIAC, Bell's relay calculators, IBM systems, and the old differential analyzer were all operational there. In a September 1949 report, each was allocated its own niche: ENIAC performed best with long, simple calculations; the Bell V model calculator handled complex calculations better due to its virtually unlimited tape length for instructions and ability to work with floating-point numbers, while IBM could process very large amounts of information stored on punch cards. Meanwhile, certain operations, such as extracting cube roots, were still easier to perform manually (by combining the use of tables and desktop calculators) to save machine time.
The best mark for the completion of the electronic computing revolution will not be 1945, when ENIAC was born, but 1954, when the IBM 650 and 704 computers emerged. These were not the first commercial electronic computers, but they were the first to be produced in the hundreds and established IBM's dominant position in the computer industry for thirty years. In the terminology of , electronic computers ceased to be a strange anomaly of the 1940s, existing only in the dreams of outcasts like Atanasoff and Mauchly; they became a normal science.
One of the many IBM 650 computers ā in this case, a specimen from Texas A&M University. The magnetic drum memory (at the bottom) made it relatively slow, but also relatively inexpensive.
Leaving the Nest
By the mid-1950s, the design and structure of digital computing equipment had detached from its origins in the switches and amplifiers of analog systems. The workings of computers in the 1930s and early 1940s heavily depended on ideas from physics and radar laboratories, especially notions from telecommunications engineers and research departments. Now computers had carved out their own field, and specialists in this area were developing their own ideas, vocabulary, and tools to solve their unique problems.
The computer emerged in its modern sense, and so our nears its conclusion. However, the world of telecommunications had one more interesting card up its sleeve. The vacuum tube surpassed the relay due to the absence of moving parts. The last relay in our history had the advantage of having no internal parts at all. A harmless-looking lump of matter with a few wires sticking out emerged thanks to a new branch of electronics known as 'solid-state.'
Although vacuum tubes were fast, they remained expensive, large, hot, and not particularly reliable. They couldnāt be used to create, say, a laptop. In 1948, von Neumann wrote that "it is unlikely we will surpass a count of 10,000 switches (or possibly several tens of thousands) while we are forced to use current technologies and philosophy." Solid-state relays allowed computers to repeatedly surpass these limits, breaking through them many times; to enter the realms of small businesses, schools, homes, appliances, and fit into pockets; to create a magical digital world that permeates our existence today. To trace its origins, we need to rewind the clock fifty years back and return to the intriguing early days of wireless technology.
What else to read:
- David Anderson, āWas the Manchester Baby conceived at Bletchley Park?ā, British Computer Society (June 4th, 2004)
- William Aspray, John von Neumann and the Origins of Modern Computing (1990)
- Martin Campbell-Kelly and William Aspray, Computer: A History of the Information Machine (1996)
- Thomas Haigh, et al., Eniac in Action (2016)
- John von Neumann, āFirst Draft of a Report on EDVACā (1945)
- Alan Turing, āProposed Electronic Calculatorā (1945)
Source: habr.com
