Book review: The Cryotron Files

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Picture credit: popsciencebooks.blogspot.com

I found this book, published simultaneously in the US and the UK in 2018 (Icon Books Ltd., London, 2018), fascinating. It is cowritten by Iain Dey & Douglas Buck, and it is is subtitled: “The strange death of a pioneering Cold War computer scientist”. You could be forgiven for thinking, on the basis of the book’s main title, that it is fictional, possibly science fiction; but it isn’t: it is a narrative of what we have to accept (given the somewhat murky reputation of some of the organisations involved) as the truth, and the subject of the book is the father of one of the authors, Dudley Buck. Even if you feel you are reasonably well informed about how science & technology, especially that appertaining to computers, have developed over the last 80 years, from its hesitant beginning with Colossus at Bletchley Park, I think it is fairly unlikely that you would have heard of a cryotron. Even though (and without worrying about revealing any significant element of the narrative) this was ultimately a ‘blind alley’ for computers as we know them in common usage nowadays, it was fundamental to the development of computing in a wider sense than what we, as the vast majority of non-specialist users know of as computing, from our smartphones and laptops.

Those of you with any knowledge of etymology will have guessed that the stem of the word cryotron indicates cold, freezing or frost, and it is derived from the Greek kruos, icy cold, frost; this compound name was coined by Dudley Buck for his invention that he thought would revolutionise computing, and it is almost risible in its simplicity, and yet its operation is marvellously efficient, the biggest requirement being that it (or in common usage, they, in significant multiples) had to be contained within an environment as close to a temperature of absolute zero as possible. The device consisted of literally nothing more than two pieces of thin metal wire: a straight section, and another that was coiled tightly around it with a ‘tail’ on each side (you can see it, tiny though it is, in Buck’s right hand in the above photograph, comparing its size with a contemporary vacuum valve); so, an input and an output. Depending upon the presence or absence of an electric current, this switch could be considered closed or open: the absolute minimum required for a binary switch, which could produce a positive or negative result – yes, or no, which is the ridiculously simple premise that allows all computers to function (although quantum computers, now reaching a fairly sophisticated stage of development, will muddy the waters somewhat).

Have you ever heard of Dudley Buck? I certainly hadn’t, hitherto. It was clear from an early age that he was gifted in all-round terms, and after the tragic accident suffered by his mother when he was only twelve, he & his younger sister were sent from their home in San Francisco to live with his father’s mother in Santa Barbara. It was there that he was able to satisfy his curiosity for all things mechanical & electrical, using a spare garage on his grandmother’s property. The family was god-fearing, so Dudley was included in all the religiosity, but that didn’t preclude him from the occasional mischief, including producing a stink bomb from the lab equipment he had hauled to bible camp one year! He joined the local Eagle Scout troop, and made a friend with whom he attended evening classes in radio electronics; before long, they set up what is claimed to be one of the first mobile disc jockey businesses in California. This was late 1942, and “World War II was in full force, but it was all happening too far away to completely disrupt the flow of life in central California”; although Dudley’s self-built radio system did attract the unwelcome attention of the Federal Communications Commission. Despite having to surrender his equipment to be dismantled, the positive outcome was that, a few months later, “Dudley was plucked out of high school and sent on a fast-track training scheme for America’s best and brightest.”: a very sensible response!

After completing his college education in the V12 program, at Seattle, Washington, which was “a  fast-track officer-training scheme that would mix undergraduate study in a few chosen disciplines with the rigors [sic] of naval training”, Ensign Dudley Buck was posted to the navy’s communications headquarters in Washington, D.C., which is when his involvement with the various security services began, and very possibly set him on the path to his untimely, early death. Although the immediate circumstances that caused his death are known, the big question mark that hangs over it is whether the Russian security services could have somehow engineered it. Somewhat surprisingly, given the vehemence of the McCarthy purges which were concurrent, there was also a willingness to share scientific research, especially in the field of computers, with the Russians; however, it was expected that this would would be a reciprocal arrangement, which was not always the case, and the research that was shared was carefully selected, because computers were increasingly being used in the euphemistically named “defence” sector, for the purposes of both detecting & targeting missiles. Buck had been working with the newly-formed National Security Agency (NSA), and the already existing CIA, including a secret mission in Berlin, although this was overseen by the highly secret 7821 Composite Group: “… a covert CIA operation run by a man who would later be dubbed the Spy of the Century … Reinhard Gehlen”. Before this, though, he had gained entry in early July, 1950, to the prestigious MIT, although not without some strings being pulled on his behalf. It was there that he had the idea for the cryotron, and was able to start developing it.

The first reciprocal trips involving the Soviets, after a couple of false starts, took place in the summer of 1958, after which a bigger exchange was suggested by the Americans. The Soviets wanted to see “among others, the young assistant professor at MIT whom the Russians believed was building the guidance system for America’s intercontinental ballistic missile.” The Russians were aware that Dudley Buck was one of the expected headline speakers lined up for the Eastern Computer Conference that December, in Philadelphia; the conference went ahead, but without the exchange, “and Buck was indeed a star performer.” The following April, a group of seven Russian scientists travelled to the US for a series of meetings & demonstrations at various locations, one of which was MIT, where they were eager to meet Dudley Buck, but: “Ever patriotic, Buck clearly just didn’t want to show them his work. … The group left MIT that night full of questions, not least about the cryogenic computer that they had not been able to see.” Around this time, Buck had begun working on electron lithography, but to achieve this required some very volatile chemicals, and they were not easy to obtain; it wasn’t until May 18th that the parcel of chemicals arrived. With hindsight, it would be very easy to condemn Buck for the careless way he handled the chemicals, which appear to have caused the fatal illness that killed him within three days, but the strange thing is that his assistant, who was very close by during the handling, was entirely unaffected. The main concern is that the Russian visitors could have somehow engineered this, but it is difficult to see how. Perhaps it was just an bizarre & tragic coincidence; the fact remains, however, that the Russians were aware Buck was a leader in his field, and the potential military applications of his work, so there will always be a question mark over his death.

It is possible that if he had lived through this early period of development, Buck might have been able to overcome the limitations of the ultra-cold environment for his technology, but it had to be modified quite extensively to be used in any practical application; according to Snyder’s official history of NSA computing projects, the cryotron “‘proved not to scale to high speed operation as had been hoped.’ The detailed explanation of how the cryotron was used and what went wrong with it remains classified. It seems that it never was used as a missile guidance system, in spite of the time that was spent on the idea; the semiconductor took that crown.” Sadly, Buck’s family earned next to nothing from his work and, outside the confines of the well-informed, Buck’s name quickly became a footnote in history, but his work was fundamental to the development of computer technology, even though, as is usually the case in most highly developed countries since the second world war, all technology has to be a slave to the military. The details I have given here only scratch the surface of Buck’s story and his achievements, but I can highly recommend this book, and as I said at the beginning, it’s a fascinating read.