WEBVTT - TechStuff Classic: A Series of Tubes Part One 0:00:04.400 --> 0:00:07.760 Welcome to tech Stuff, a production from I Heart Radio. 0:00:12.080 --> 0:00:15.200 Hey there, and welcome to tech Stuff. I'm your host 0:00:15.320 --> 0:00:18.040 job in Strickland. I'm an executive producer with iHeart Radio. 0:00:18.079 --> 0:00:20.880 And how the tech are you? It is time for 0:00:21.000 --> 0:00:24.160 us to listen to a classic episode of tech Stuff. 0:00:24.200 --> 0:00:28.440 This one published April. It is part one of a 0:00:28.480 --> 0:00:31.560 two part series. So that's a spoiler for next week, 0:00:31.680 --> 0:00:35.320 right anyway, this one is titled A Series of Tubes 0:00:35.920 --> 0:00:40.319 Part one. Enjoy. So one of the cool things that 0:00:40.400 --> 0:00:43.479 you brought to light is that, uh, you know that 0:00:44.360 --> 0:00:47.120 these are not just little systems that are used within 0:00:47.280 --> 0:00:52.040 like that bank single building to take your bank receipt 0:00:52.120 --> 0:00:53.920 to the teller when you don't feel like getting out 0:00:53.920 --> 0:00:56.720 of your car, right, That these actually used to be 0:00:57.000 --> 0:01:01.560 and in some cases maybe still are much more senses. Yeah. See, 0:01:01.760 --> 0:01:05.319 there used to be these huge networks of tubes buried 0:01:05.360 --> 0:01:08.000 beneath the cities that let people send messages to each 0:01:08.000 --> 0:01:13.360 other faster than ever before. Yeah, I've heard of this 0:01:13.720 --> 0:01:18.000 the Internet. It's a it's a series of tubes. Uh no, no, 0:01:18.120 --> 0:01:21.480 before before the Internet, our ponet but that was only 0:01:21.520 --> 0:01:26.160 like three computers and it was it was in Wow. Yeah, 0:01:26.360 --> 0:01:29.760 pneumatic tubes date back quite a ways. And so yeah, 0:01:29.760 --> 0:01:31.920 when when Lauren said we're going to talk about a 0:01:31.959 --> 0:01:33.600 series of tubes, I thought we were going to talk 0:01:33.640 --> 0:01:36.679 about the whole you know, good old Senator Ted from 0:01:36.680 --> 0:01:39.480 Alaska talking about how the Internet is a series of tubes, which, 0:01:39.520 --> 0:01:42.080 by the way, just for the record, I think is 0:01:42.120 --> 0:01:45.720 a decent analogy. Yeah, yeah, I mean it was. I mean, 0:01:45.760 --> 0:01:47.880 it is funny, but it was. And also, as it 0:01:47.880 --> 0:01:50.680 turns out, some telecom cables are currently being housed in 0:01:50.720 --> 0:01:54.000 old pneumatic tubes. So it is a series of tubes. 0:01:54.280 --> 0:01:59.360 Yeah awesome. So what exactly is a pneumatic tube. Well, 0:01:59.480 --> 0:02:01.760 it is eight hipeline that uses air pressure to move 0:02:01.760 --> 0:02:05.560 a canister from one point to another. Okay, that seems 0:02:05.600 --> 0:02:09.359 pretty simple. So like it seems pretty simple, but wait, 0:02:09.560 --> 0:02:13.400 there's more, uh there? Yeah, I mean, these things have 0:02:13.480 --> 0:02:16.760 come a very long way as technology has advanced up, 0:02:16.880 --> 0:02:21.360 motors have advanced. Motors started existing, like like, electricity wasn't 0:02:21.400 --> 0:02:26.600 really a thing when tube started up. Computers happened, right, 0:02:26.680 --> 0:02:29.120 And actually you might think, well, computers would end up, 0:02:29.639 --> 0:02:34.040 you know, making the whole purpose of these things obsolete, 0:02:34.120 --> 0:02:37.000 but that's not the case. In fact, there's still very 0:02:37.080 --> 0:02:40.920 high tech pneumatic tube systems that are at play in 0:02:41.040 --> 0:02:44.560 various locations for good reasons. And it turns out that 0:02:44.560 --> 0:02:47.240 the computers aren't necessary elements in that in order to 0:02:47.280 --> 0:02:50.520 be kind of like traffic control. So it's kind of 0:02:50.560 --> 0:02:54.440 cool that this thing that we would normally think was 0:02:54.480 --> 0:02:59.919 replaced by computers is actually complementing them in specific use cases. Obviously, 0:03:00.320 --> 0:03:02.840 if you want to send a message to your friend 0:03:02.919 --> 0:03:06.560 across town, you're more likely to either drop a letter 0:03:06.560 --> 0:03:09.160 in the mail or much more likely to send the 0:03:09.240 --> 0:03:15.440 message Kingdom on face. But there are many important uses 0:03:15.520 --> 0:03:18.919 for pneumatic tubes. Um. We will get into many of 0:03:19.000 --> 0:03:23.320 those later. First, let us talk specifically about how pneumatic 0:03:23.400 --> 0:03:26.239 tubes work. Yeah, let's talk about the physics what is 0:03:26.320 --> 0:03:30.160 going on with a pneumatic tube? And so walk me 0:03:30.320 --> 0:03:34.760 through the you wrote. You've you've described an excellent way 0:03:35.320 --> 0:03:37.440 of thinking through this so that we have a logical 0:03:37.480 --> 0:03:41.560 progression to get to the actual mechanics of pneumatic tubes. Okay, 0:03:41.880 --> 0:03:45.800 So pneumatic, in case you don't know, means works via 0:03:45.920 --> 0:03:50.920 pressurized gas. Basically. Um, So the air around us seems 0:03:51.000 --> 0:03:54.120 pretty thin, right, but it's actually a soup. It's actually 0:03:54.160 --> 0:03:57.360 a liquid made up of lightweight atoms and particles like 0:03:57.680 --> 0:04:01.400 nitrogen and oxygen and argon and carp dioxide and ozone 0:04:01.480 --> 0:04:04.360 and dust bunnies and et cetera. Yeah, yeah, uh, And 0:04:04.520 --> 0:04:07.560 that soup is at pretty much a constant density and 0:04:07.680 --> 0:04:10.880 pressure around us while we're walking around on Earth's surface, 0:04:11.200 --> 0:04:13.720 though it's a little bit thinner. The further away from 0:04:13.800 --> 0:04:16.280 sea level you get, right, Right, the higher you climb 0:04:16.360 --> 0:04:19.600 on a mountain, for example, the less dense the air. 0:04:19.880 --> 0:04:24.320 Thus you have let lower air pressure at those altitudes. Right, 0:04:24.400 --> 0:04:27.520 And it's useful to think about that because one great 0:04:27.520 --> 0:04:32.240 way of thinking about air pressure and how it helps 0:04:32.240 --> 0:04:34.719 stuff work is by thinking of how your ears pop 0:04:34.800 --> 0:04:37.280 when you go up in a really tall elevator or 0:04:37.680 --> 0:04:39.880 or up a mountain, or up in an airplane. Um, 0:04:40.440 --> 0:04:43.280 And that's because your your ears pop because of the 0:04:43.760 --> 0:04:46.880 density of the air outside of your body being lower 0:04:47.080 --> 0:04:50.040 than the density of the air in your ears. Okay, 0:04:50.200 --> 0:04:53.360 You've got this little tube of air in your in 0:04:53.440 --> 0:04:57.160 your head called the station tube, and it lets your 0:04:57.240 --> 0:04:59.400 it lets your ear drum vibrate, which is important for 0:04:59.440 --> 0:05:02.080 your ear dry to function. Right, That's what allows you 0:05:02.240 --> 0:05:06.960 to interpret sound right, because sound is a physical uh phenomenon. 0:05:07.120 --> 0:05:12.680 It vibrates the ear drum, which makes some celia go, well, yeah, 0:05:13.360 --> 0:05:17.479 that signals the brain that exactly. Yeah, we're just gonna 0:05:17.640 --> 0:05:20.840 re enact once more with feeling line by line. But no, 0:05:21.000 --> 0:05:23.280 it it does. You know. The ear drum is what 0:05:23.520 --> 0:05:26.240 ends up causing these other bones in your in your 0:05:26.279 --> 0:05:29.040 ear to move in such a way that celia inside 0:05:29.480 --> 0:05:33.800 of this one container, uh start to vibrate fluctuate, and 0:05:33.880 --> 0:05:35.960 that sends electrical signals to your brain, which then is 0:05:36.000 --> 0:05:40.640 interpreted as sound. So without that vibration, you don't hear. Uh. 0:05:40.760 --> 0:05:43.520 And without this tube you wouldn't get that vibration. That 0:05:43.560 --> 0:05:45.560 would have nothing to vibrate against. It would just be 0:05:45.640 --> 0:05:49.640 all solid meat and that doesn't vibrate as well. Yeah yeah, 0:05:49.760 --> 0:05:51.920 I mean sound can travel through solids, but it's not 0:05:52.000 --> 0:05:55.080 as effective going from air to solid then from solid 0:05:55.120 --> 0:05:58.120 to solid, so you know it's important. So the C 0:05:58.279 --> 0:06:01.200 station tube is shut off with muscles that are tied 0:06:01.240 --> 0:06:04.880 into your mouth throat swallowing muscles. This is one of 0:06:04.920 --> 0:06:06.760 those things I always thought was weird that that our 0:06:06.839 --> 0:06:10.400 ears are connected to I mean, the human bodies. Gross y'all, 0:06:11.240 --> 0:06:14.760 especially the sinus type system. Yeah, and that's that's why 0:06:14.800 --> 0:06:18.320 if you swallow, you hear like a tiny little pop, 0:06:18.800 --> 0:06:21.520 and that is the muscles of that tube opening up 0:06:21.640 --> 0:06:24.320 and and letting a fresh supply of air in, which 0:06:24.400 --> 0:06:26.760 is important because the air that gets into the tube 0:06:27.240 --> 0:06:29.000 gets absorbed by the walls of the tube, and so 0:06:29.120 --> 0:06:32.120 it needs to be replenished periodically. That's also why your 0:06:32.120 --> 0:06:34.560 head hurts so much when when you have a cold, 0:06:34.680 --> 0:06:38.680 because those muscles get stuffed up by gunk and you 0:06:38.760 --> 0:06:41.600 can't replenish that air supply and everything hurt. When you're like, 0:06:41.800 --> 0:06:43.919 I can't hear because I have a cold, it seems 0:06:44.240 --> 0:06:48.120 because yeah, yeah, that's because the because your ear drum 0:06:48.240 --> 0:06:51.120 literally cannot vibrate because there's not a replenishment of air 0:06:51.480 --> 0:06:53.320 in the tube. That's kind of cool. I mean, I 0:06:53.800 --> 0:06:56.400 had never thought of it that way. So interesting. Okay, 0:06:56.480 --> 0:06:58.560 so all of this is a sidebar promise. We're getting 0:06:58.560 --> 0:07:02.920 back to pneumatics. UM. So, so as you gain altitude, 0:07:03.720 --> 0:07:07.640 the air inside of your ears starts exerting pressure on 0:07:07.800 --> 0:07:12.120 those membranes. Um, it starts pushing because it's at that 0:07:12.280 --> 0:07:17.040 higher density than the air outside. Um. You know, it 0:07:17.120 --> 0:07:20.720 wants to be chill like that lower pressure air, you 0:07:20.880 --> 0:07:24.280 never let it hang loose. Yeah, when you create this 0:07:24.440 --> 0:07:27.640 pressure differential than there, that's where you're starting to get 0:07:27.760 --> 0:07:30.720 that feeling of something's just kind of like you get 0:07:30.760 --> 0:07:34.000 that ache. You can get pretty painful too, if you 0:07:34.400 --> 0:07:37.320 especially like you know, you hear about babies and kids 0:07:37.400 --> 0:07:40.320 having real problems because they haven't figured out how to 0:07:41.040 --> 0:07:45.760 voluntarily open up their irustration tube. Yeah. And so when 0:07:45.800 --> 0:07:48.400 the difference in pressure is great enough that you either 0:07:48.560 --> 0:07:52.240 voluntarily or involuntarily open up that illustration tube, that the 0:07:52.320 --> 0:07:55.760 sudden release of that pressurized air is pretty forceful and 0:07:55.880 --> 0:07:59.440 creates that pop. That's when your ears go pop um. 0:07:59.760 --> 0:08:03.640 But is just one example of pressure at work around us. Uh. 0:08:04.040 --> 0:08:05.480 This next one that I've got for you is a 0:08:05.520 --> 0:08:08.000 little bit more technical. Okay are you ready? Yeah? Okay, 0:08:08.120 --> 0:08:12.040 straws like what the pig built his house out of, 0:08:12.760 --> 0:08:16.240 drinking straws. Okay, okay, so crazy straws in my case, 0:08:16.320 --> 0:08:19.520 but yeah, sure, sure, crazy straws totally. So you're not 0:08:19.800 --> 0:08:23.760 technically pulling liquid up through a straw. You're you're creating 0:08:23.840 --> 0:08:27.160 an opportunity for the liquid to push itself up. So 0:08:27.720 --> 0:08:31.600 I'm motivating the liquid. You're motivating the liquid. Yeah, exactly. Yeah. 0:08:31.760 --> 0:08:34.679 This section that you apply with your mouth creates an 0:08:34.760 --> 0:08:37.400 area of low pressure at the top of the straw, 0:08:37.840 --> 0:08:40.719 which means that the relatively high pressure liquid at the 0:08:40.760 --> 0:08:43.800 bottom of the straw pushes a sip of your drink 0:08:44.080 --> 0:08:46.839 up into your mouth. Now, this is really interesting to 0:08:46.960 --> 0:08:50.000 me because I talked about a similar thing with Josh 0:08:50.120 --> 0:08:54.160 Clark when we covered how toilets work, because we had 0:08:54.160 --> 0:08:58.360 to talk about siphoning and the siphoning and uses a 0:08:58.440 --> 0:09:01.920 similar principle and it does quire this difference in pressure 0:09:01.960 --> 0:09:07.280 as well. So very interesting. So how does this compared 0:09:07.320 --> 0:09:11.280 to say, pneumatic tubes. Well, it's it's basically the same thing. Um, 0:09:12.200 --> 0:09:14.720 the the tube part is air tight like a straw, 0:09:15.600 --> 0:09:18.400 except it has sealable hatches at either end instead of 0:09:18.559 --> 0:09:22.240 you know straw. Bit's yeah. Um, so so you you 0:09:22.360 --> 0:09:24.599 put a canister in one hatch. Yeah, it helps a 0:09:24.640 --> 0:09:26.240 whole lot off. The canister has some kind of like 0:09:26.320 --> 0:09:29.680 flexible skirts on either end, the concealed the interior edges 0:09:29.720 --> 0:09:32.720 of the tube that air is not passing around around 0:09:32.920 --> 0:09:36.000 the canister right to make it the most effective. So 0:09:36.200 --> 0:09:38.120 you so you put your canister in there, you close 0:09:38.200 --> 0:09:40.960 the hatch, and you press your go button. Um. Now 0:09:41.080 --> 0:09:43.200 on the other end of the tube, pressing that button 0:09:43.280 --> 0:09:46.480 will open up a vent and start a motor. Now, 0:09:47.200 --> 0:09:49.120 one of two things will happen at this point, right, 0:09:49.280 --> 0:09:52.160 So this all depends upon where the canister is in 0:09:52.320 --> 0:09:54.920 relation to where the blower is. Right. So here's the 0:09:55.000 --> 0:09:57.360 boring one, because because you get to take the really 0:09:57.440 --> 0:09:59.920 cool one. Here's the boring one if the canister is 0:10:00.040 --> 0:10:02.679 the blower side. So in other words, this is like 0:10:02.840 --> 0:10:06.760 the blower being a fan essentially that can either blow 0:10:06.880 --> 0:10:09.280 air into the tube or pull air out of the 0:10:09.360 --> 0:10:11.640 tube if it's on the blower side, and the only 0:10:11.679 --> 0:10:13.160 way to move the canster to the other end of 0:10:13.200 --> 0:10:16.599 the tube is to blow air against the canister pushing it. 0:10:16.720 --> 0:10:19.679 So you're increasing the air pressure on the side of 0:10:19.800 --> 0:10:23.439 the blower and it just blows the canister across. So 0:10:23.520 --> 0:10:25.680 this is essentially the same as when you shoot blow 0:10:25.760 --> 0:10:29.240 darts at your coworkers, or when I say you when 0:10:29.320 --> 0:10:32.839 I shoot blow darts at Ben bowling. Um, he has 0:10:32.880 --> 0:10:35.760 wondered what that tingling sensation has been, and no one 0:10:35.880 --> 0:10:39.880 tell him. But that's essentially it yeah, but if the 0:10:39.960 --> 0:10:42.319 canisters on the opposite side, See the blower on a 0:10:42.320 --> 0:10:45.760 pneumatic tube system typically is at just one end. You 0:10:45.800 --> 0:10:48.560 don't have two blowers right right, And it's not um. 0:10:49.760 --> 0:10:53.520 Especially classically, these things weren't always powerful enough to necessarily 0:10:53.720 --> 0:10:57.440 push right. So if the canisters on the opposite end, 0:10:57.960 --> 0:11:00.719 like I, I've sent something out now, I'm expecting it 0:11:00.840 --> 0:11:03.719 to come back, but my blower is at the the 0:11:04.080 --> 0:11:06.280 end where I am at, I have to I have 0:11:06.400 --> 0:11:08.280 to find a different way to move the canster. I 0:11:08.360 --> 0:11:10.920 can't push it by by turning the fan to blow 0:11:11.000 --> 0:11:13.920 air into the tube. So what do I do? Then, Well, 0:11:14.200 --> 0:11:17.520 the motor will still drive a fan down at the 0:11:17.600 --> 0:11:20.559 other end of the tube, but but this time it 0:11:20.600 --> 0:11:24.480 will start to pull air out of the tube, venting 0:11:24.559 --> 0:11:27.840 it out of the tube entirely. Gotcha. Okay, this section, 0:11:28.440 --> 0:11:31.480 just like a straw, creates a partial vacuum at that 0:11:31.760 --> 0:11:33.839 end of the tube with the fan an area of 0:11:33.960 --> 0:11:38.000 low pressure. So uh, you know, down down at the 0:11:38.160 --> 0:11:41.680 canister end of the tube, the higher pressure air behind 0:11:41.880 --> 0:11:46.120 the canister wants to expand to settle the difference, right, um, 0:11:46.400 --> 0:11:49.319 so it will push the canister through the tube. So 0:11:49.400 --> 0:11:51.959 the canstor is still being pushed. It's just that it's 0:11:51.960 --> 0:11:54.559 being pushed because the air behind it is at a 0:11:54.640 --> 0:11:57.080 higher pressure than the air in front of it, exactly. 0:11:57.400 --> 0:12:00.240 It's so cool. So in most of these systems, when 0:12:00.240 --> 0:12:03.599 the canister reaches its destination um like the end of 0:12:03.679 --> 0:12:06.559 the tube, it will trigger a trapdoor to close behind it, 0:12:06.679 --> 0:12:08.960 which will also cue the motor to turn off end 0:12:09.040 --> 0:12:12.360 the vnced close, meaning that the partial vacuum that's been 0:12:12.400 --> 0:12:15.320 created in the tube will be broken, and your buddy 0:12:15.360 --> 0:12:17.160 at the other end can open up the hatch and 0:12:17.400 --> 0:12:19.720 take out the canister. And that makes perfect sense because 0:12:19.760 --> 0:12:22.920 obviously if you had continue to have that vacuum they're 0:12:23.040 --> 0:12:25.880 opening up the hatch would have been difficult, it real hard, yeah, 0:12:26.160 --> 0:12:28.520 because that that air pressure on the outside of the 0:12:28.559 --> 0:12:31.120 tube is pushing against it. You know. It's this same 0:12:31.160 --> 0:12:32.920 sort of deal. That's just one of those things that 0:12:33.240 --> 0:12:35.800 you have to have all the lower parts in place 0:12:35.880 --> 0:12:38.480 for the system to work properly. And the big advantage 0:12:38.520 --> 0:12:40.640 of this sort of system is that you don't have 0:12:40.720 --> 0:12:43.520 to connect little motors to all those canisters, right. The 0:12:43.600 --> 0:12:47.240 individual units don't need anything, they don't need any moving parts. Yeah, 0:12:47.320 --> 0:12:49.760 the whole. The system is a whole can have a 0:12:49.880 --> 0:12:52.280 single well, it can have a single motor. A lot 0:12:52.320 --> 0:12:55.040 of the time these days, they've got really complex multiple 0:12:55.160 --> 0:12:57.679 motor things that's going on, especially if you have like 0:12:58.640 --> 0:13:02.360 lots of potential destination systems. But but if you had 0:13:02.360 --> 0:13:04.120 a very simple system where it was just an out 0:13:04.160 --> 0:13:07.600 and back, you would just need one one motor turning 0:13:07.679 --> 0:13:10.600 one fan or or you know, some people just refer 0:13:10.679 --> 0:13:13.240 to him as air compressors, but technically you're using a 0:13:13.320 --> 0:13:17.640 fan anything fan. Yeah. So yeah, that's really interesting. And 0:13:18.720 --> 0:13:23.280 they are also some interesting advantages or rather design elements 0:13:23.480 --> 0:13:26.760 that have been made to make sure that the canisters 0:13:26.840 --> 0:13:32.320 arrived safely, because in the original systems, canisters would arrive 0:13:32.440 --> 0:13:35.560 by basically just crashing into the opposite end of the two. Yeah, 0:13:35.679 --> 0:13:38.520 they and they could be going pretty darn fast, depending 0:13:38.559 --> 0:13:41.679 on how powerful that fan was. Yeah, tens of miles 0:13:41.720 --> 0:13:43.920 an hour, which which I mean usually I say is 0:13:44.000 --> 0:13:46.400 kind of a joke, but actually that's pretty quick. Yeah, 0:13:46.559 --> 0:13:48.880 especially for something like if you haven't designed it just right, 0:13:48.960 --> 0:13:51.400 it's gonna you know, just just smash it up, yeah, 0:13:51.640 --> 0:13:53.840 or it's gonna end up causing damage to the tubes, 0:13:53.880 --> 0:13:56.520 and obviously that's a problem. So there are a couple 0:13:56.520 --> 0:14:00.040 of different ways of slowing them down properly. One of 0:14:00.080 --> 0:14:03.319 those uses air brakes, which is essentially just again pressurized air, 0:14:03.400 --> 0:14:06.280 but now on the low pressure side, so that can 0:14:06.360 --> 0:14:09.600 slow down the canister from you know, it's it's inevitable 0:14:09.679 --> 0:14:14.959 crash towards oblivion, or bumpers like little rubber bumpers that 0:14:15.040 --> 0:14:17.520 can come out from the sides to slow like the 0:14:17.600 --> 0:14:22.000 way a lot of roller coaster brakes work. Huh. And 0:14:22.280 --> 0:14:25.000 also they often have some form of switch that once 0:14:25.040 --> 0:14:27.880 a canister passes that switch, it activates it, which then 0:14:28.000 --> 0:14:31.120 turns off power to the blower. Uh. Now, momentum still 0:14:31.160 --> 0:14:34.120 a thing, so you have to plan for that as well. 0:14:35.560 --> 0:14:38.200 But yeah, yeah, it's sort of like the trapdoor idea, 0:14:38.320 --> 0:14:40.840 but with a little bit of a longer glide after 0:14:41.000 --> 0:14:44.480 the trapdoor. Right. So now I'm going to try and 0:14:44.680 --> 0:14:49.680 explain without the use of visual aids, how how a 0:14:49.920 --> 0:14:53.800 simple pneumatic tube system using a couple of valves and 0:14:54.160 --> 0:14:57.600 a switch would help a canister come to a stop. 0:14:58.040 --> 0:15:02.160 All right, So you've got with the two valves, these 0:15:02.320 --> 0:15:04.640 create a pathway for air in front of the caster 0:15:04.840 --> 0:15:07.520 to vent out for most of the trip, while leaving 0:15:07.640 --> 0:15:09.680 enough for the very end to act as a cushion. So, 0:15:09.840 --> 0:15:12.280 in other words, you need a way for air to 0:15:12.400 --> 0:15:14.840 vent outward or else you'll never create that area of 0:15:14.880 --> 0:15:17.120 low pressure. But you need a way to keep a 0:15:17.200 --> 0:15:19.000 little bit of air in there so that it can 0:15:19.080 --> 0:15:21.960 act as a breaking system. So you've got to figure 0:15:21.960 --> 0:15:24.320 out how to do that. And when I saw there 0:15:24.400 --> 0:15:28.640 was a a series of illustrations I saw online that 0:15:28.800 --> 0:15:32.040 explained this really well. And uh so I'm going to 0:15:32.200 --> 0:15:34.440 try and walk you through it the best way I 0:15:34.520 --> 0:15:38.480 know how. So we're playing Dungeons and Dragons, y'all. And 0:15:38.600 --> 0:15:42.720 here's here's what's happening. So your adventurer is in a 0:15:42.840 --> 0:15:46.960 tunnel and behind you as a giant spinning fan of death. 0:15:47.280 --> 0:15:50.080 Oh yeah, I think I've been on this module before. Okay, 0:15:50.160 --> 0:15:52.920 So in this case, the giant spinning fan of death 0:15:53.040 --> 0:15:55.680 is currently slow. It's it's actually not even moving at all. 0:15:55.800 --> 0:15:59.440 It's it's no one's trip that trap. Yet you start 0:15:59.560 --> 0:16:01.960 walking down the tunnel. So the van is behind you 0:16:02.200 --> 0:16:04.320 and you just have a big expansive tunnel in front 0:16:04.320 --> 0:16:07.400 of you. Now, as you walk down the tunnel, you 0:16:07.480 --> 0:16:10.200 see that there is a split from the tunnel off 0:16:10.280 --> 0:16:13.520 let's say to your left, and it's just a second, 0:16:13.680 --> 0:16:16.600 smaller tunnel that you see down the door. No, no, no, 0:16:16.680 --> 0:16:18.600 there's no door. It's just just an open it's just 0:16:18.680 --> 0:16:21.800 an opening. But but I like your initiative. You didn't 0:16:21.800 --> 0:16:23.920 even have to roll for it, all right. But you 0:16:24.000 --> 0:16:27.040 continue on down and you come to your first actual 0:16:27.120 --> 0:16:30.600 door in that main tunnel. Now you can do your kicking, 0:16:31.520 --> 0:16:34.520 and it works because that door will only open outward 0:16:34.760 --> 0:16:36.960 into the main hall. This is a valve, and it's 0:16:36.960 --> 0:16:40.520 a one way valve, right, so air can go from 0:16:40.640 --> 0:16:43.920 the fan through the main pipe, but it can't be 0:16:44.040 --> 0:16:48.120 sucked back this way, got it? So if airs, if 0:16:48.200 --> 0:16:51.400 airs being pulled, that door slam shut and nothing, not 0:16:51.600 --> 0:16:55.360 even your mighty kick will open it. So since there 0:16:55.400 --> 0:16:58.000 are no differentials in air pressure, your kick opens the door. 0:16:58.120 --> 0:17:01.440 You continue down the hall. I gonna skip the cobalt encounter. 0:17:02.640 --> 0:17:05.840 As you continue down the tunnel, you see a door 0:17:06.040 --> 0:17:10.080 on your left. Now, this door is the other valve. 0:17:10.240 --> 0:17:13.200 This is the valve that is the bypass valve. And 0:17:13.359 --> 0:17:15.280 in fact, if you were to kick down that door, 0:17:15.480 --> 0:17:17.800 but you can do oh ah, yeah, I kicked down 0:17:17.840 --> 0:17:20.720 the door. Excellent, So the door opens inward into that 0:17:21.240 --> 0:17:25.320 secondary tunnel. There's no bug bears. There is an al bear, 0:17:25.520 --> 0:17:29.359 but he's currently on break. So you kick down the door. UH. 0:17:29.520 --> 0:17:33.320 That opens the pathway to the bypass UH top tube 0:17:33.400 --> 0:17:37.359 or bypass pipe. So the first tunnel that you passed 0:17:37.400 --> 0:17:39.920 way back when on the left, it's the same, it's 0:17:40.000 --> 0:17:44.440 that same pathway. So this door will only open when 0:17:44.520 --> 0:17:48.119 air is being pulled through back toward the fan, so 0:17:48.800 --> 0:17:51.560 sucked back toward the fan. So that way, you always 0:17:51.600 --> 0:17:54.080 have one valve that's open and one valve that's closed, 0:17:54.400 --> 0:17:56.399 and it all depends upon air flows, so there's no 0:17:56.520 --> 0:18:00.800 mechanical or electrical need to to change these valves. It's 0:18:00.840 --> 0:18:03.560 just the airflow that does it automatically. So if the 0:18:03.600 --> 0:18:06.440 air flow is being pulled back, the bypass valve is open, 0:18:06.920 --> 0:18:10.040 the main valve is shut, and because the bypass pipe 0:18:10.520 --> 0:18:14.200 completely bypasses that main valve, air can still flow through. 0:18:15.040 --> 0:18:18.080 So now we're going to have to use a an 0:18:18.160 --> 0:18:22.240 example to talk about what happens when the canister comes by. 0:18:22.359 --> 0:18:26.320 So the canister starts rocketing down the path toward the 0:18:26.480 --> 0:18:30.400 fan side, so air is being pulled through, it ends 0:18:30.440 --> 0:18:33.119 up passing a switch. That switch tells the fan to 0:18:33.240 --> 0:18:35.399 stop blowing by. Of course that's going to take a 0:18:35.400 --> 0:18:38.640 little time, So the cancer continues down towards the pathway. 0:18:39.480 --> 0:18:44.120 The canister ends up passing that bypass valve, which is open. 0:18:44.760 --> 0:18:48.080 So once the canister is cleared the bypass valve, because 0:18:48.200 --> 0:18:50.680 you have an air tight seal between the main valve 0:18:50.760 --> 0:18:54.399 and the canister, that air between the two starts to 0:18:54.480 --> 0:18:58.040 get compressed, and that compressed air begins to push back 0:18:58.119 --> 0:19:00.800 against the canister, slowing it down, and thus you have 0:19:00.960 --> 0:19:03.879 air brakes. That was a long way to go over 0:19:03.960 --> 0:19:07.240 that explanation, but honestly, without the use of visual aids, 0:19:07.320 --> 0:19:10.399 I wasn't sure how it is going to explain how 0:19:10.520 --> 0:19:13.479 this actually works in a way that would remotely make sense. Uh, 0:19:14.320 --> 0:19:17.159 you now get two d and thirty gold pieces a 0:19:17.240 --> 0:19:22.000 piece and the princess is in another castle. Okay, okay, well, 0:19:22.080 --> 0:19:25.800 good adventure than You're welcome. I'm a level three game 0:19:25.840 --> 0:19:29.800 mess thro um. Yeah. So obviously, if the if the 0:19:29.840 --> 0:19:31.840 fan were switched the other way, where the canstor is 0:19:31.880 --> 0:19:35.520 blowing down the the pipe, the main valve would be opened. 0:19:35.520 --> 0:19:38.280 The bypass valve would be shut, and that would be 0:19:38.359 --> 0:19:41.680 it there would it would be no different otherwise. Uh So, yeah, 0:19:41.840 --> 0:19:44.560 that's that's the basic way that this works. And that's 0:19:44.720 --> 0:19:50.640 you know, that's a very very very simple versions, as 0:19:50.720 --> 0:19:54.200 complicated as that just sounded out loud, that that is 0:19:54.480 --> 0:19:59.120 as basic as it gets. Really. Yeah, Jonathan from two 0:19:59.240 --> 0:20:01.159 coming in here. We're going to have more from this 0:20:01.280 --> 0:20:16.080 classic episode after this quick break. You know, I said 0:20:16.080 --> 0:20:18.160 a while ago that these things have been around since 0:20:18.200 --> 0:20:21.200 the eighteen fifties at least. So let us go to 0:20:21.320 --> 0:20:24.920 the way back machine. It's been out of use for 0:20:25.080 --> 0:20:35.720 so long. Kind of dusty in here, this little Yeah, 0:20:35.960 --> 0:20:39.200 you know what, as as as cramped as this thing is, 0:20:39.480 --> 0:20:43.119 it's still cooler than Josh and Chuck Studio. I mean, 0:20:43.240 --> 0:20:46.360 not not like in a style sense, I mean physically 0:20:46.440 --> 0:20:50.359 the temperature is lower. Physically Yeah, cooler, Yeah, yeah that No, 0:20:50.520 --> 0:20:53.439 they they're they're pretty hot, yeah they are. They're there 0:20:53.520 --> 0:20:55.880 a couple of hot guys. All right, Well, anyway, let's 0:20:55.920 --> 0:21:01.600 just where are we setting this to, uh too, to Greece? Sure, well, okay, 0:21:02.040 --> 0:21:06.400 like ancient Greece, modern Greece. Okay, I was really hoping 0:21:06.440 --> 0:21:08.240 you were going to say Greece too, but okay, to 0:21:08.720 --> 0:21:13.119 Greece it is here we go. Well, we do have 0:21:13.280 --> 0:21:16.520 chills and they are multiplying. But that was Greece one. 0:21:16.520 --> 0:21:22.359 I'm sorry, I don't want to it's it says a 0:21:22.400 --> 0:21:24.879 lot for you and little for me. So there was 0:21:24.960 --> 0:21:28.400 a mathematician who started writing about the concept of using 0:21:28.440 --> 0:21:31.800 pressurized guests to produce mechanical motion. I know this guy, Yeah, 0:21:32.080 --> 0:21:37.280 Haro of Alexandria, also known as Heron. He's a pretty 0:21:37.320 --> 0:21:39.840 smart dude. Was he was? Did you you know? We 0:21:39.920 --> 0:21:41.720 talked about it. He is. Since we are here in 0:21:41.760 --> 0:21:44.800 the way back missions and he's across the street over there, 0:21:45.240 --> 0:21:47.360 he's kind of working on something else right now, Yeah, 0:21:47.440 --> 0:21:49.560 I think we're weirding him out by looking at him. Maybe. Okay, 0:21:49.560 --> 0:21:53.640 well let's just act casual, all right. So something else 0:21:53.680 --> 0:21:55.800 that he was really known for, by the way, he 0:21:55.920 --> 0:21:58.960 was known for working with steam engines, in fact, pressurized gas. 0:21:59.040 --> 0:22:02.520 It makes sense, right, it's related. He noticed that air 0:22:03.240 --> 0:22:07.480 had the ability to physically push against things, and that 0:22:07.560 --> 0:22:11.520 if you had a way of generating air movement, you know. 0:22:11.640 --> 0:22:14.360 He even thought, oh, air must be made of something 0:22:14.440 --> 0:22:17.879 because it can have a force. So very forward thinking. 0:22:18.320 --> 0:22:20.440 He didn't have the words to describe this in the 0:22:20.520 --> 0:22:23.399 way that we do today, but he understood that this 0:22:23.520 --> 0:22:25.080 had a way of doing work, and that if you 0:22:25.080 --> 0:22:27.359 could find a way to channel that, you can make 0:22:27.480 --> 0:22:29.320 air do work for you. And that gave him a 0:22:29.359 --> 0:22:32.560 lot of thought about steam, including one of my favorite 0:22:32.800 --> 0:22:37.080 proposed inventions. There's no record of it actually existing, and 0:22:37.440 --> 0:22:39.480 I think we I think we talked about this one 0:22:39.600 --> 0:22:42.120 in our episode about steam engines. Yeah, I'm pretty sure 0:22:42.200 --> 0:22:45.679