[ Transcription: Screenshots of a Facebook post by Bruce Lindner. The post reads:
Around 10-12 years ago (when he was still a spry youngster in his nineties), my dad suggested to my brother's family and mine, that we jot down a list of any of my parent's household items we'd like to have once both he and my mother had passed on. That way, there will be no question about who gets the hutch, or the couch, or whatevs. Ever the pragmatist, my dad. So that's what we did.
I myself have little interest in the monetary value of their trappings, as much as I do the potentially historical value. So I jotted down that I'd like to have his old slide rule. He saw that on my list and asked; "Why the hell would you want that piece of crap?" I told him because of its role in the Manhattan Project, it has historical value. Isn't that the same one you used at Hanford, Los Alamos and Oak Ridge? He confirmed. Then he asked; "Do you want the abacus too?" 😦
You used an abacus on the Manhattan Project? Seriously?
Sure. How do you think we tracked complex calculations before computers came along?
I never really thought about it. Sure. Put me down for the abacus too. 🤔
He told me to go ahead and take them then and there. No one else was interested, so have at them. So I did.
The history of this slide rule is itself kind of interesting. He bought it second hand in 1939 from someone in Chicago for $3.00, because he couldn't afford a brand new one, which sold for $11.75. I've researched this particular model. It was patented in 1908, manufactured in 1932 by an outfit called Keuffel & Esser in New York. The model number is 4092-3. It is a "log log duplex" type slide rule (whatever the hell that means). He even kept the original leather case, which its previous owner scrawled weird shapes into. My dad covered them over with a stylized M L, his initials.
Keuffel & Esser remained in business for decades. But then in 1975, the market for slide rules skidded into the porcelain fixture when, not coincidentally, the pocket calculator came along. They were ultimately swallowed up by AZON Corporation in 1987.
As for the abacus, have no way to determine its date of manufacture, or by which company-it has no markings on it whatsoever, which suggests to me that it was provided by the government. My dad can't recall where he got it. Oh, and the "technology" of the abacus goes back a bit farther... the first known use of an abacus was by the Sumerians, in the 3rd millennium B.C. So, 5,000 years, give or take.
So what's the relevant history of THIS particular abacus, and THIS particular slide rule? These two "computers" were the very devices used to determine the properties, yield, and half life of plutonium. So, yeah. I wanted them. 🤨
End Transcription. ]
