February 15: The World’s First General Purpose Digital Electronic Computer is Dedicated at the University of Pennsylvania

This Day In History: February 15, 1946

On this day in history, 1946, the first ever general purpose digital electronic computer was dedicated at the University of Pennsylvania.  The machine was called the ENIAC (Electronic Numerical Integrator and Computer).  It cost over $500,000 (around $6 million today), weighed around 57,000 pounds and took up 1800 square feet.  Further, it featured 17,468 vacuum tubes, 70,000 resistors, 7,200 diodes, 10,000 capacitors, and most impressively of all there were around 5 million joints that needed to be hand-soldered. In order to power all this, it took a whopping 150 kW of electricity. This is enough to power about 114 homes in the U.S.

ENIAC was the brainchild of several different people, most notably John Mauchly and J. Presper Eckert.  Four years before ENIAC’s auspicious debut, Mauchly wrote a memo outlining the incredible speed boost one would be able to get if, rather than relying on mechanical, moving parts, a computer was designed to use only digital electronics.  This memo came to the attention of Lieutenant Herman Goldstine of the U.S. Army, who then asked Mauchly to create a formal proposal for Goldstine to give to the army.  Mauchly did so and the army contracted with him and J. Presper Eckert on June 5, 1943 to create the machine, under the code-name “Project PX”.

There was already at this time several different other computers available, but they either weren’t built to be “general purpose” or relied on electromechanical parts, which drastically reduced the speed in which they could perform calculations.  The ENIAC was both general purpose and was a fully digital electronic computer.  One of its more impressive attributes was its ability to perform around 5,000 additions per second, or 357 multiplications per second, which was around 1000 times faster than other machines of the day.  On top of the basic mathematics calculations (add/subtract/divide/multiple/square root), it also was capable of doing conditional branches, loops, and Input/Output.  Most importantly, it was a Turing complete machine, which just means it was capable of doing anything a theoretical single-taped Turing machine can do.  For those not familiar, why this is important, in layman’s terms, is that it means that it can basically be used to solve any computational problem that is solvable (in theory, though not in practice because of the real world limits on system resources).

Its first task was to perform calculations aiding in the development of the hydrogen bomb.  More than one million I/O cards were produced for this one task, which ultimately proved to be a successful trial run.  This task was run at the behest of mathematician John von Neumann, who was working on the Manhattan project and who later accidentally lent his name to the “Von Neumann Architecture” of computers that is still commonly used today.

The ENIAC ran for about 9 months straight before being shut down for upgrades to the memory system.  It was then moved and put back together and powered back up seven months later and stayed on for the next 8 years, being used continuously, performing a variety of tasks, such as calculating artillery tables for the military and doing various calculations for aeronautics, meteorology, etc.

It should be noted that von Neumann had that particular computer architecture incorrectly named after himself due to a memo he wrote First Draft of a Report on the EDVAC on June 30, 1945 (EDVAC being the successor to the ENIAC, designed at the same school where the ENIAC was in the final stages of being completed and with many of the same people working on the project as were working on the ENIAC, including Eckert and Mauchly).  The paper was basically a synopsis, written using formal logic, outlining the ideas the group had been discussing on creating a general purpose stored program computer.  As it was meant to be more of a memo, rather than a published paper, he never mentioned the names of all the people who’d helped developed the architecture and indeed, already had done the majority of the design before von Neumann became a consultant on the project (particularly Eckert and Mauchly).

When he sent his hand written notes back to Philadelphia, Lieutenant Herman Goldstine had them typed up and distributed to the 24 people involved in the EDVAC project, listing von Neumann as the sole author, as it wasn’t intended to be distributed beyond those working on the project.  However, due to widespread interest in the report, he had it copied and sent to various other educational and government institutions, where it was further copied and spread all over the world, with von Neumann ending up getting most of the credit, though he wasn’t a major part of that project.  As such, we now call it the “Von Neumann Architecture,” even though it wasn’t really his design and would probably be more accurately called the Eckert-Mauchly Architecture.

This is to take nothing away from von Neumann who was truly an amazing individual who had a significant impact on a variety of fields including quantum mechanics, computer science, economics, geometry, and many more. (The full list is amazingly long.) He was one of the brightest people in the world, accomplishing an amazing amount in the 53 years he lived. He died of cancer, possibly due to his exposure to radiation while working on the Manhattan project.  Isreal Halperin, a mathematician who worked with him said, “Keeping up with him was impossible. The feeling was you were on a tricycle chasing a racing car.”  One of Von Neumann’s professors, George Pólya, who himself had a pretty impressive resume also stated: “Johnny was the only student I was ever afraid of. If in the course of a lecture, I stated an unsolved problem. He’d come to me at the end of the lecture with the complete solution scribbled on a slip of paper.”

Von Neumann also had a true photographic memory.  As Goldstine noted:

“One of his remarkable abilities was his power of absolute recall. As far as I could tell, von Neumann was able on once reading a book or article to quote it back verbatim; moreover, he could do it years later without hesitation. He could also translate it at no diminution in speed from its original language into English. On one occasion, I tested his ability by asking him to tell me how The Tale of Two Cities started. Whereupon, without any pause, he immediately began to recite the first chapter and continued until asked to stop after about ten or fifteen minutes.”

When he was dying in the hospital, von Neumann also reportedly whiled away the hours with his brother by playing a game of reciting from memory the first few lines of each page of the play, Faust.

If you’re interested in more on von Neumann, I’d recommend picking up his biography: John Von Neumann: The Scientific Genius Who Pioneered the Modern Computer, Game Theory, Nuclear Deterrence, and Much More, by Norman MacRae.  It’s not the best biography in the world, in terms of how the author wrote it, but a fascinating read nonetheless and arguably the most complete single book on von Neumann.

Bonus Facts:

  • One simple example of von Neumann’s genius was when he was presented with the following problem: “Two bicyclists start twenty miles apart and head toward each other, each going at a steady rate of 10 mph. At the same time a fly that travels at a steady 15 mph starts from the front wheel of the southbound bicycle and flies to the front wheel of the northbound one, then turns around and flies to the front wheel of the southbound one again, and continues in this manner till he is crushed between the two front wheels. Question: what total distance did the fly cover?”  There is a simple trick to solving this, but von Neumann did it the complicated way… in his head… in a matter of seconds.  Basically, he took the sum of the infinite series in his head and spit out the answer within seconds after the question was asked.
  • If you’re curious, the simple answer really is quite simple and just about anyone who sees the trick should be able to answer it in a matter of seconds, no genius required…  *spoiler ahead*:  The simple solution is just to realize that the two bicycles are traveling for exactly one hour (twenty miles apart, going straight at each other at a rate of 10 mph).  Thus, if the fly is traveling back and forth between them at a rate of 15 mph, it must have traveled exactly 15 miles in that hour.  The fact that it went back and forth is inconsequential.   Obviously it can also be solved the way von Neumann did it, but I don’t think I’ve ever met anyone who could do that in a couple seconds in their head, and I’ve met several true geniuses.  Apparently, there’s genius, compared to normal people, then there’s von Neumann genius, who was a genius compared to geniuses. 😉
  • Von Neumann also managed to get both a degree in chemical engineering at the Federal Institute of Technology in Zurich and a Ph.D. in mathematics  at the University of Budapest… at the same time, starting at the age of 17 and finishing at the age of 22, despite the fact that it was two different fields and the universities were about 600 miles apart.
  • Another interesting, slightly less flattering factoid about von Neumann was that he was quite the ladies’ man, and not always in a good way.  For instance, he had a habit of attempting to look up the skirts of the various secretaries working at Los Alamos during WWII when they were sitting at their open front desks.  As a result of this, the secretaries would put cardboard in place to block the opening in their desks.  This “girl-gawking” was apparently a habit of his he indulged in frequently.
  • The group involved in making the EDVAC was further upset by the First Draft of a Report on the EDVAC being widely sent out as an official publication because this paper now made it so that the EDVAC design unpatentable.  It also ultimately helped get the ENIAC patent invalidated some 27 years later as its architecture was very similar to the EDVAC.  I’m guessing Goldstine wasn’t the most popular member of the group after having von Neumann’s notes typed up and distributed.
  • One of the chief criticisms of the ENIAC when it was being built came from skeptics who felt that while in theory this was a great idea, it wouldn’t be practical because the vacuum tubes would blow out constantly, making it expensive to maintain and requiring the machine to be unavailable for computations for long periods of time through the day and night while tubes were replaced.  In reality, though, this wasn’t really a problem because most of the tubes that were going to go out quickly tended to do so when it was powering up or powering down.  To get around this problem, they simply left the computer on all the time.  This was expensive (150 kW and all), but reduced the tube failure rate to only about 15 per month, and it took only about 15 minutes to locate and replace a malfunctioning tube.  Given how few computers there were in the world and that it was one of the fastest out there by far at the time, there was always work for it, so it wasn’t sitting around idle, wasting money on electricity.
  • The longest time between vacuum tube failures was 4 days and 20 hours.
  • In total, it took about 200,000 man hours to create the ENIAC.
  • Besides helping design the ENIAC and EDVAC, among others, and helping design the most successful general purpose computer architectures to date (the von Neumann architecture), Dr. Mauchly also founded the Association for Computing Machinery (ACM), which pretty much anyone involved in Computer Science should be familiar with; it being the world’s largest educational computing society today.  He also helped found the Society of Industrial and Applied Mathematics (SIAM).
  • Dr. Mauchly and Dr. Eckert also started the world’s first commercial computer company, the Eckert-Mauchly Computer Corporation.
  • The process of programming the ENIAC was long and tedious, being done primarily by six women who were later inducted into the Women in Technology International Hall of Fame.  Those women were: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas, and Ruth Lichterman.
  • The first ever computer programmer was also a women, Ada Lovelace.  She became the world’s first computer programmer 104 years before the ENIAC made its debut.  You can read more about this here: In 1842, Ada Lovelace Wrote the World’s First Computer Program
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