Hey, this is prop from the hood politics with prop podcast. And this what we do here. We take all these highfalutin political ideas and things in the news and explain it to you in a language that we all speak in, just like, I don't know, take filibustering. Believe it or not, you already know what that is, because if you got a mama that don't play no games, you've been filibustering your whole life. Hey, mom. No, look, listen, mom, before you make your decision, what had happened was everything said after that is filibuster. You just trying to stall her out to avoid the inevitable. Congress do it all the time. See, you already knew, so listen to hood politics with props on the iHeartRadio app, Apple Podcasts, or wherever you get your podcast.

Hey, and welcome to the short stuff. I'm Josh. And there's Chuck. And Jerry's here, too. Dave's here in spirit. When you put us all together, you can call us the blue man group. The best I could come up with on short notice, Chuck.

Yeah.

This is the, I guess, the conclusion of our two part series on colors, although we have done colors in the past. I know we did Indigo, and I think we did a short stuff on haint blue, right?

Yes.

And some other stuff. It's come up in some other things, but I think colors is going to be a never ending suite. There's a lot of colors to cover.

That's right. And this is a story of not only a color, but a process. And we're talking about the color Prussian blue. And that is the color of a blueprint. Like in the old days when blueprints were really blue. Like blueprints for a house or a building or a bridge.

Right.

Or a tank or whatever. You're going to design that. Blue is called prussian blue.

Yeah.

And, I mean, if you go and look up blueprints up to about the would say, you are going to find actual blue blueprints, like you said. And there was a guy named John Herschel. He was an english astronomer, chemist, and photographer. And this is back when photographer is really something. This is the 1840s. In 1842, he figured out that prussian blue is photoreactive, meaning that when you expose it to light, you can get prussian blue. And he figured out that you could use that chemical reaction to make copies of things. It's extraordinarily clever, and I think John Herschel deserves to be in the inventor's hall of fame for this.

Is he not?

I don't know if he is. He deserves to be there. If not, he deserves to be there.

I agree. So this is the process. It's called cyanotype, and it was what early photographers used. In fact, the very first published photography book was made with cyanotype.

Yeah. By the way, that was by Anna Atkins, whose 1843 book, photographs of british algae. Get this, Chuck. Colon. Cyanotype impressions.

Amazing. So all of a sudden, architects and engineers were all over this stuff as well, because they realized, hey, if you can make a photograph using this cyanotype process, you can make a copy of something. And we're really tired of redrawing everything over and over.

Right, exactly. So the process involves producing blue ferric ferrocyanide. That's the chemical name for prussian blue. And you'll notice there's a lot of ferric stuff in there. That means it's made from iron salts, but it also has cyanide in it. And just from researching this episode, Chuck, I finally understood what cyan as a blue refers to. It's referring to cyanide.

Yeah.

Did you know that already?

No.

Well, I thought that was pretty cool.

That's awesome.

But if you take a drawing of something and you can put it on something that's basically see through these days, they use, like, clear plastic. If you're doing something like this, and you have a line drawing, and you put that line drawing on top of a paper that's been treated in blue ferric ferrous ionide, these iron salts that make that, and you expose it to light. Then the paper beneath that's treated in the prussian blue turns blue in every place except for where those lines were on top of it.

Yeah.

So it's like a photo image in a dark room, and, in fact, you have to do it in a dark room, just like you would a photograph. So that's why they would draw it in regular ink on paper. And then the reverse negative image of that would be white drawing on blue paper and a really nice looking blue.

Yeah, it's a gorgeous blue. Prussian blue is fantastic.

Yeah, man. I was typing in prussian blue things, and I saw some suit jackets, some wool suit jackets. Prussian blue.

Gorgeous.

Yeah.

You'd look like a member of the prussian army from the 19th century.

That's right. That's why they named it that.

Right? Yeah.

Do you want to take a break and then come back and talk about where your prussian blue came from?

Let's do it.

Well, now, when you're on the road driving in your truck, why not learn a thing or two from Josh and Chuck. It's stuff you should know. All right.

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So, prussian blue finds its origins in the laboratory of an alchemist and a dye maker, of all places. It's a pretty cool place for a new thing to be created, especially something as beautiful as prussian blue. And the alchemist was a guy named Johann Conrad Dippel. How would you say Conrad in German, Chuck?

That's probably right.

Conrad. Or Conrad.

I don't know, actually.

Okay, well, we'll just call him Mr. Dipple. He was the alchemist air Dipple. Air dipple.

Yeah.

He was the alchemist, and the dye maker was a guy named Diesbach. We're just going with Mr. Diesbach for this guy. And they shared this lab in Berlin. And by sharing a lab and sharing one another's or using, like, borrowing, I should say, a cup of one another's ingredients here or there, they ended up accidentally creating prussian blue.

Yeah, exactly. I think the chemist was working on medicines like elixirs and things, and Diesbach, as a dye maker, was great at making these dyes. And as the story goes, he was making a deep red dye one day when he borrowed some potash from his chemist friend, and that turned it into this wonderful, wonderful prussian blue. He went back in hair dipple and said, I got to figure out what this stuff is. And he figured out the secret was that the potash had ox blood. And when he mixed that with the iron sulfate that caused this amazing blue to. What does it do? Does it unveil itself?

Yeah, that's a great way to put it. So prussian blue has unveil itself. And at first, they called it Berlin blue, and it only became known as prussian blue later on because it was used to dye the uniforms of the prussian army in the early 19th century. And depending on what part of the continent you were on, or whether you were on the continent at all, calling it prussian blue was either a term of endearment or a term of disparagement, because the Prussians helped save the British's cookies at Waterloo and defeated Napoleon. So if you were French, you didn't think very highly of the Prussians or their blue. If you were English, it was a term of endearment, because you were really grateful to the Prussians for coming and saving the day there.

That's right. And it became just a popular color. Like, artists loved using it, printmakers loved using it. Obviously, these architects loved the result of using it. I'm not sure if they especially love the color. That was just kind of what color blueprints turned out to be, but I'm sure they were fine with it. But Herschel died before that blueprinting process was born. I think five years later is when the actual architectural blueprint process that is unfortunately gone, because I think it looks really neat these days. You're not going to find that, because over the years, a lot of different things happened to either make it fall out of fashion or just make it cheaper and safer and easier to make copies in different ways.

I would bet that there's some hipster artisan architectural firm that still uses this process now, you think has gone back to it.

Yeah.

But the reason that has largely been abandoned is because it's a very labor intensive and time intensive process, even if you're using kind of updated machinery and other processes came along that seemed to do a better job. And plus, also, I don't know if everybody's like, we're sick of the blue, or whatever, because there's another process called diazo white press, and it does the same thing, but it gives you, like, black or gray lines on a white background. And that's kind of what the architectural plans look like today. They don't look blue anymore. And then shortly after that, they came up with zero graphic copiers, which you just today call a copier. And I didn't realize this either, Chuck. They're called zero graphic because this is a dry process. Like zero. Like dry. Like zero scaping. It's a dry process because you don't have to wet the paper that is receiving the image like you do when you're using the old prussian blue cyanotype process.

Yeah.

And I think that's how Xerox got their name.

Right.

Yeah, for sure. Which is a proprietary eponym.

Yeah.

And I thought the diazo process created blue lines. Is that not true?

I think later on, they figured out that if you use blue lines on the original, it makes a cleaner line on the copy. That was my take on it.

All right. And I think that was sort of, like, in the. In the early, when the diazo process started to kind of fade away, because ammonia is not something you want to be working with a lot. And there were also regulations that increased in working with ammonia. And then the digital revolution came along. Print technology, things that were cheaper, basically, and smaller. All of a sudden, you didn't have to have some huge plot printer in your office to make something like this. And it did, like everything. It became cheaper and smaller and faster.

Yeah.

And I think the printers that can print out, like, regulation size architectural plans or engineering plans, those became more affordable, too. And they're basically just xeroxes. They're like printers, essentially, just bigger size. One thing I did see, Chuck, that I didn't realize, pen plotters, it's like a contraption originally, where you have a pen, and connected to that pen is a bunch of other pens. And so when you're drawing on one paper, the other pens are drawing on their own paper, so you're making copies like that as you're drawing in the first place. Those have come back, and they're now computerized.

Yeah, plotters are super cool. I had a friend years ago that was a sign maker, and these plotters would cut out these designs from the computer files. And it's just really cool to see those things that automation at work, even for a small business. He was like a team of one. The other thing I wanted to mention, too, is I think the diazos faded in sunlight.

Okay.

Which, it was fine for a little while because apparently it takes like, a few months, which was enough. If it's like a house plan or something, you don't need it to last forever. But eventually they were like, we should probably make something a little more permanent.

That connects some dots for me, because I saw on some archivist website that they do not recommend using the diazo print because it's so impermanent. Now I have it. Knowing's half the battle, as they say.

Cyan.

Cyan. Chuck the cyan. I followed up with the cyan, too, and everybody. That means short stuff is out.

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