WEBVTT - TechStuff Classic: History of Electricity Part One 0:00:04.440 --> 0:00:12.360 Welcome to tech Stuff, a production from iHeartRadio. Hey there, 0:00:12.360 --> 0:00:15.920 and welcome to tech Stuff. I'm your host, job and Strickland, 0:00:15.920 --> 0:00:18.840 I'm an executive producer with iHeart Podcasts and how the 0:00:18.920 --> 0:00:21.919 tech are you? So it is Friday, It's time for 0:00:22.000 --> 0:00:24.960 a classic episode, which means we dive into the tech 0:00:25.000 --> 0:00:28.080 Stuff archive and pull out an episode from our past 0:00:28.200 --> 0:00:32.040 to listen to. This one, originally published on June twenty eighth, 0:00:32.120 --> 0:00:36.440 twenty seventeen, is called The History of Electricity Heart one, 0:00:37.120 --> 0:00:39.880 which kind of spoils what we're going to be talking 0:00:39.880 --> 0:00:44.760 about in next week's classic episode, but you know, there's 0:00:44.800 --> 0:00:48.080 no gain around it. I hope you enjoy this classic episode. 0:00:49.560 --> 0:00:54.720 So first, let's define what electricity is, or rather, instead 0:00:54.720 --> 0:00:57.720 of letting me define it, let's use Miriam Webster, because 0:00:57.760 --> 0:01:01.400 that's kind of their job. Electricity is a fundamental form 0:01:01.440 --> 0:01:04.840 of energy, observable in positive and negative forms, that occurs 0:01:04.920 --> 0:01:08.800 naturally as in lightning, or is produced as in a generator, 0:01:09.000 --> 0:01:11.480 and that is expressed in terms of the movement and 0:01:11.600 --> 0:01:16.319 interaction of electrons. That's actually kind of a little simplistic. 0:01:16.560 --> 0:01:18.959 It's talking about the move of electrons. It's really more 0:01:19.000 --> 0:01:24.280 about the move of electric charge and not of electrons. Specifically, 0:01:24.720 --> 0:01:29.080 if you had some other carrier that was carrying electric charge, 0:01:29.360 --> 0:01:31.679 it would be more about the movement of that carrier. 0:01:32.440 --> 0:01:36.080 As it turns out, electrons are the naturally occurring negatively 0:01:36.160 --> 0:01:40.800 charged particles sub atomic particles that are concerned, especially with electronics. 0:01:41.360 --> 0:01:44.880 So it's understandable, but I just want to point that 0:01:44.920 --> 0:01:47.280 out that it's really more about electric charge and less 0:01:47.319 --> 0:01:52.040 about the actual sub atomic particles. Don't worry, even though 0:01:52.040 --> 0:01:55.520 we'll be talking a lot about electrons. I promise this 0:01:55.640 --> 0:01:59.880 show won't be too negative. I'm seriously done with pun 0:02:00.200 --> 0:02:03.440 for just a bit now. To further define electricity, it 0:02:03.480 --> 0:02:06.080 helps if we get some basic ideas established. Now, keep 0:02:06.120 --> 0:02:10.160 in mind these aspects of electricity were not understood for centuries. 0:02:10.200 --> 0:02:13.399 So when I go into the history of electricity, remember 0:02:13.480 --> 0:02:18.240 that for the vast majority of our experience working with 0:02:18.520 --> 0:02:22.040 and trying to understand electricity, we did not have any 0:02:22.120 --> 0:02:28.919 knowledge of the underpinning foundational physics. Right we were making 0:02:28.960 --> 0:02:32.679 observations and we were even building things that could take 0:02:32.720 --> 0:02:36.480 advantage of this stuff, but we didn't actually understand what 0:02:36.480 --> 0:02:37.959 it was doing or how it was working, which I 0:02:38.000 --> 0:02:41.280 always find really fascinating this idea that we can harness 0:02:41.360 --> 0:02:45.520 something without fully understanding what it is and how it works. 0:02:46.280 --> 0:02:49.120 But it's good for us, as in myself and you 0:02:49.160 --> 0:02:52.160 guys the audience, to understand some of these basics before 0:02:52.240 --> 0:02:55.440 we get too far into the discussion. Otherwise I have 0:02:55.560 --> 0:02:59.400 to keep interrupting the history lesson for science lessons, and 0:02:59.440 --> 0:03:02.480 then it gets kind of a little complicated. Some of 0:03:02.520 --> 0:03:04.760 that's gonna happen anyway, but I want to get the 0:03:04.760 --> 0:03:11.960 foundation out of the way. So the most important thing 0:03:12.000 --> 0:03:15.360 to remember here is that we're talking electric charge, and 0:03:15.400 --> 0:03:17.720 we want to make sure we can make sense of this. 0:03:17.840 --> 0:03:21.000 It's time to get current on our terms. So I 0:03:21.000 --> 0:03:24.880 guess that really wasn't the last pun I'll be talking about. 0:03:24.919 --> 0:03:28.560 So electric charge comes in two flavors, positive and negative, 0:03:28.880 --> 0:03:31.919 positive charge and negative charge. You're probably very familiar with this. 0:03:32.280 --> 0:03:35.560 On the sub atomic particle level, pot you know, we 0:03:36.040 --> 0:03:39.600 have our protons, those are positively charged. We have our electrons, 0:03:39.600 --> 0:03:43.560 those are negatively charged. Now, opposite charges attract one another 0:03:44.280 --> 0:03:47.960 in circuits. A carrier moves negative charges to a source 0:03:48.120 --> 0:03:52.880 of positive charge. So some sort of sub atomic particle 0:03:53.000 --> 0:03:56.760 needs to carry that negative charge throughout a circuit until 0:03:56.760 --> 0:03:59.160 it can get to the source of a positive charge. 0:03:59.440 --> 0:04:04.080 Because negative quote unquote wants to be with positive. It 0:04:04.120 --> 0:04:08.000 doesn't really want anything, it's just that's the natural tendency, 0:04:08.160 --> 0:04:12.880 right these for these two different charges to attract one another. Now, 0:04:13.040 --> 0:04:16.600 in practical terms, the carrier is an electron. So that's 0:04:16.600 --> 0:04:19.280 why we talk about electricity, it's why we talk about electronics. 0:04:20.480 --> 0:04:24.120 It's the subatomic particle that possesses negative charge. So if 0:04:24.120 --> 0:04:28.560 we do a basic electrostatic experiment where we take a 0:04:28.600 --> 0:04:31.440 block of wax and we rub that block of wax 0:04:31.480 --> 0:04:34.919 with some wool, we will build up an electrostatic charge. 0:04:35.000 --> 0:04:38.719 So what's happening is we are imparting a negative charge 0:04:38.760 --> 0:04:43.200 to the wax and creating a positive charge to the wool. So, 0:04:43.240 --> 0:04:46.200 in practical terms, that means the wax has a surplus 0:04:46.240 --> 0:04:50.919 of electrons and the wool has a deficiency of electrons. Effectively, 0:04:50.960 --> 0:04:53.440 you are rubbing some of the electrons from the wool 0:04:53.560 --> 0:04:56.160 onto the wax. That makes the overall charge of the 0:04:56.200 --> 0:04:58.599 surface of the wax negative. It makes the overall charge 0:04:58.640 --> 0:05:01.640 of the surface of the wall possi And if we 0:05:01.720 --> 0:05:05.880 create a pathway that electrons can follow from the wax 0:05:06.400 --> 0:05:10.679 to the woll. Then electrons will take that pathway pop 0:05:10.720 --> 0:05:14.320 back over to the wool and sort of repair that 0:05:14.400 --> 0:05:20.000 deficiency where that deficiency of electrons will be balanced out, 0:05:20.000 --> 0:05:23.760 where electrons will journey back over and rejoin, and they'll 0:05:23.800 --> 0:05:26.000 probably be a big party, you know, or at least 0:05:26.040 --> 0:05:32.080 a sub atomic one. And that's the basics for electric charge. 0:05:32.160 --> 0:05:36.120 So now we have to build on this foundation. There 0:05:36.160 --> 0:05:39.680 are three other basic concepts that we need to understand, 0:05:40.160 --> 0:05:44.960 and those are voltage, current, and resistance. Now these will 0:05:44.960 --> 0:05:48.000 be important throughout the discussion of electricity, particularly as people 0:05:48.000 --> 0:05:51.120 begin to get a deeper understanding of what was actually 0:05:51.200 --> 0:05:55.599 happening with electricity. Voltage is probably the trickiest one for 0:05:55.640 --> 0:06:00.240 people who aren't inclined toward electronics and electricity. It's all 0:06:00.240 --> 0:06:03.880 about potential energy, specifically the potential energy represented by a 0:06:03.880 --> 0:06:08.840 pair of different electric charges. So voltage is sort of 0:06:08.920 --> 0:06:11.800 like pressure. You can imagine it as a force that 0:06:11.960 --> 0:06:16.200 pushes electrons through a conductor, which is oversimplifying, but it's 0:06:16.240 --> 0:06:18.920 helpful when you imagine it that way. So voltage is 0:06:18.960 --> 0:06:22.479 the pressure in the system. The higher the voltage, the 0:06:22.520 --> 0:06:26.480 greater the pressure, the stronger that push is a low 0:06:26.600 --> 0:06:29.760 voltage has very little push, while high voltage has a 0:06:29.760 --> 0:06:32.440 whole lot of push, and we need voltage to make 0:06:32.480 --> 0:06:36.000 electronics work. Otherwise nothing is going to cause a current 0:06:36.040 --> 0:06:38.960 to flow through a circuit. You can also kind of 0:06:39.000 --> 0:06:41.960 think of it as potential energy in the form of 0:06:42.960 --> 0:06:46.520 as an analogy of kinetic energy. So let's say that 0:06:46.560 --> 0:06:49.279 you have a level surface upon which you've got a 0:06:49.279 --> 0:06:53.599 two little corrals of marbles. They don't really have any 0:06:53.600 --> 0:06:56.000 potential energy with respect to one another, they're on the 0:06:56.000 --> 0:06:58.720 same level. But let's say you raise one of those up. 0:06:58.720 --> 0:07:00.240 You tilt it and you raise it up, so the 0:07:00.279 --> 0:07:03.320 corral is still holding the marbles in. But now the 0:07:03.320 --> 0:07:06.159 marbles have potential energy because they're at a higher level 0:07:06.720 --> 0:07:09.400 than the lower marbles. And then let's say you were 0:07:09.440 --> 0:07:12.800 to connect a little slide between the top corral and 0:07:12.840 --> 0:07:15.880 the bottom corral and allow the marbles to roll down 0:07:15.960 --> 0:07:19.400 the hill. Well, this would be sort of like a 0:07:20.600 --> 0:07:25.080 copper wire connecting an area that has a surplus of 0:07:25.120 --> 0:07:28.160 electrons to an area that has a deficiency of electrons. 0:07:28.920 --> 0:07:33.560 It's allowing for the movement of those electrons. Now, in 0:07:33.600 --> 0:07:37.280 the case of voltage, we're really talking about electric potential. 0:07:37.360 --> 0:07:41.840 Here we're not talking about kinetic energy or potential energy 0:07:41.880 --> 0:07:45.000 that could be converted into kinetic energy. Is really just 0:07:45.040 --> 0:07:48.400 meant as an analogy. So when we talk about voltage, 0:07:48.400 --> 0:07:51.360 we talk about it with respect of two points on 0:07:51.440 --> 0:07:54.880 a circuit. So a voltage difference between two points on 0:07:54.920 --> 0:07:58.520 a single circuit and their potential difference really which we 0:07:58.600 --> 0:08:02.360 may also call a voltage. The potential difference between two 0:08:02.400 --> 0:08:06.240 points is measured in a unit called volts. No big 0:08:06.240 --> 0:08:08.960 surprise there. A volt is the amount of energy needed 0:08:09.000 --> 0:08:12.520 to force an electrical current of one ampier more on 0:08:12.560 --> 0:08:15.560 that in a second, through a resistance of one ome 0:08:15.880 --> 0:08:19.800 more on that in a second two at a particular temperature. Now, 0:08:19.840 --> 0:08:22.600 you can have a voltage between two points without having 0:08:22.680 --> 0:08:25.840 any connection between them, So you can have a voltage 0:08:25.880 --> 0:08:28.600 between two things that do not have an active pathway 0:08:28.760 --> 0:08:33.800 between the two. If the distance between the two points 0:08:33.960 --> 0:08:40.480 is decreased, then that electrostatic field that the voltage difference 0:08:40.600 --> 0:08:46.079 creates will intensify. If you increase the space between those 0:08:46.120 --> 0:08:51.640 two points, the electrostatic field will diminish. So distance plays 0:08:51.679 --> 0:08:54.720 a factor, not just the difference in voltage, so that 0:08:54.760 --> 0:08:59.920 covers voltage, but now let's talk about current. So technically 0:09:00.000 --> 0:09:02.880 the current is a flow of electrical charge, and we 0:09:02.920 --> 0:09:06.240 commonly think of it as the movement of electrons, but 0:09:06.360 --> 0:09:09.600 again that's an oversimplification. You can actually have a flow 0:09:09.640 --> 0:09:12.440 of positive charge and that would still be a current. 0:09:13.040 --> 0:09:15.439 If you add a flow of positive charge, that's technically 0:09:15.480 --> 0:09:18.679 a current. But when we're talking about circuits and electronics, 0:09:18.720 --> 0:09:24.480 we're really talking about electrons, not positively charged electrical charges, 0:09:25.040 --> 0:09:27.840 So we tend to simplify it and say it's the 0:09:27.880 --> 0:09:30.360 flow of electrons. Just keep in mind that is an 0:09:30.400 --> 0:09:36.400 oversimplification because electrons are the charge carriers of negative charge. Now, 0:09:37.280 --> 0:09:39.280 in a way, you could think of it as electrons 0:09:39.320 --> 0:09:42.520 are the messengers and the electric charge they carry is 0:09:42.559 --> 0:09:46.920 the message, and that's what's really important. But in practical terms, 0:09:47.000 --> 0:09:51.040 we can just simplify it to electrons. We measure current 0:09:51.200 --> 0:09:54.560 in ampiers and that gives us a sense of the 0:09:54.600 --> 0:09:59.360 intensity or quantity of a charge. So voltage is the 0:09:59.440 --> 0:10:03.360 force behind moving a charge, and amperage tells you how 0:10:03.440 --> 0:10:07.400 much charge is actually moving. And this can help if 0:10:07.480 --> 0:10:10.960 you start to imagine voltage as being a locomotive engine 0:10:11.360 --> 0:10:14.360 and the amperage as being a series of train cars. 0:10:14.720 --> 0:10:17.520 So a low amperage current you might think of as 0:10:17.559 --> 0:10:20.640 just being two or three train cars being pushed by 0:10:20.679 --> 0:10:24.680 a locomotive engine. But you might think of a high 0:10:24.720 --> 0:10:28.360 amperage as being a series of train cars like fifteen 0:10:28.440 --> 0:10:32.200 or twenty being pushed by that same locomotive engine. In 0:10:32.200 --> 0:10:34.800 both cases, the locomotive engine is putting out the same 0:10:34.920 --> 0:10:39.000 amount of force. It's just that in one case it's 0:10:39.040 --> 0:10:42.680 pushing a relatively small number of train cars and the 0:10:42.720 --> 0:10:45.040 other one that's pushing a larger number. But the amount 0:10:45.080 --> 0:10:47.880 of force that's using for both is the same. So 0:10:48.760 --> 0:10:52.320 that's the difference between current and voltage, or if you 0:10:52.360 --> 0:10:57.839 prefer amperage and volts. Now, current will get a bit 0:10:57.920 --> 0:11:00.960 more confusing when we start talking about the direction of flow, 0:11:01.240 --> 0:11:04.120 and that's thanks to a certain founding father of the 0:11:04.200 --> 0:11:07.000 United States. But I don't want to jump ahead. We'll 0:11:07.040 --> 0:11:09.320 get there. When we get there, I'll save that for 0:11:09.360 --> 0:11:12.240 a little bit later in this episode. Finally, we have 0:11:12.320 --> 0:11:15.360 the concept of resistance, and as the name suggests, this 0:11:15.400 --> 0:11:18.280 is the property of a material to resist the flow 0:11:18.440 --> 0:11:22.079 of electric charge. A material with a very high resistance 0:11:22.280 --> 0:11:24.720 is an insulator. It does not allow electric charge to 0:11:24.760 --> 0:11:26.920 pass through it very easily. You would have to use 0:11:27.000 --> 0:11:29.839 a great deal of energy to move an electric charge 0:11:29.880 --> 0:11:33.079 through that kind of material. A material with very low 0:11:33.200 --> 0:11:36.400 resistance is a conductor. It will allow electric charge to 0:11:36.400 --> 0:11:41.760 flow through relatively easily. Now, even conductors have resistance. You 0:11:41.840 --> 0:11:46.400 have to get to very low temperatures, like super frozen 0:11:46.440 --> 0:11:50.000 temperatures almost close to absolute zero to get to super 0:11:50.040 --> 0:11:53.760 conductivity where you have zero resistance and a conductor becomes 0:11:53.800 --> 0:11:57.760 an ideal or perfect conductor. But at other temperatures there's 0:11:57.800 --> 0:12:00.920 some resistance. You can get around that by making a 0:12:01.080 --> 0:12:06.360 cable thicker. Thin cables have a higher resistance than thicker cables, 0:12:06.720 --> 0:12:10.120 But that's kind of beyond what we're talking about here. 0:12:10.400 --> 0:12:15.160 We measure resistance in Ohms and Ohm. George Ohm, who 0:12:15.200 --> 0:12:19.320 is a physician who kind of figured all this stuff out, 0:12:20.280 --> 0:12:23.040 developed Ohm's law. Now that tells us that voltage is 0:12:23.080 --> 0:12:26.800 equal to current times resistance, or you could say current 0:12:26.920 --> 0:12:30.240 is equal to voltage divided by resistance, or that resistance 0:12:30.280 --> 0:12:34.080 is equal to voltage divided by current. It's this relationship 0:12:34.120 --> 0:12:40.679 between current, resistance and voltage that is inherent in electricity 0:12:40.679 --> 0:12:45.040 and electronics. Now, those basic concepts are the very foundation 0:12:45.440 --> 0:12:49.719 for all electronics. Now, obviously it gets more complicated and 0:12:50.320 --> 0:12:52.880 you can add in all sorts of different elements besides that, 0:12:53.000 --> 0:12:54.920 with like diodes and things of that nature. But I 0:12:55.000 --> 0:12:57.960 just wanted to get that covered as the basis for 0:12:58.240 --> 0:13:01.480 the conversation that follows. And now we're going to dive 0:13:01.520 --> 0:13:06.679 into a history lesson. So humans have known about electricity 0:13:06.720 --> 0:13:11.720 in some form for millennia fales of Melitas, And I 0:13:11.800 --> 0:13:15.199 know I'm mispronouncing that, So to all my Greek historians 0:13:15.240 --> 0:13:19.680 out there, I deeply apologize, but I have little Latin 0:13:19.720 --> 0:13:25.240 and less Greek. Along with my buddy Shakespeare. Anyway, he 0:13:25.320 --> 0:13:29.880 had noted that amber, the material amber, would attract light 0:13:30.000 --> 0:13:32.840 materials to its surface after being rubbed. So if you 0:13:32.920 --> 0:13:35.840 rubbed amber with a cloth and then held it toward feathers, 0:13:35.880 --> 0:13:38.000 for example, you had notice that feathers would have a 0:13:38.040 --> 0:13:42.319 tendency to be attracted to the amber. Now, later on 0:13:42.400 --> 0:13:45.280 we would understand that this is static electricity, this is 0:13:45.320 --> 0:13:49.440 building an electrostatic charge using amber. But this was more 0:13:49.440 --> 0:13:52.000 of an observation back in those times, and this is 0:13:52.120 --> 0:13:57.880 centuries before the Common era, and in fact, the word 0:13:57.960 --> 0:14:01.480 electricity comes from the last an electrom, which in turn 0:14:01.559 --> 0:14:05.960 comes from the Greek electron, which means amber. So when 0:14:05.960 --> 0:14:09.720 we talk about electrons, that means that's the Greek word 0:14:09.760 --> 0:14:13.840 for amber. And it's because of this initial well not 0:14:13.880 --> 0:14:17.880 even initial, but this early observation. I just thought that 0:14:17.920 --> 0:14:22.120 was kind of interesting, and you would eventually learn that 0:14:22.920 --> 0:14:29.160 a future engineer scientist named this whole process electricity in 0:14:29.320 --> 0:14:34.160 honor of this early observation. Now in nineteen thirty six, 0:14:34.200 --> 0:14:36.960 we're jumping ahead just to talk about another discovery about 0:14:37.040 --> 0:14:44.000 ancient civilizations. There was a railroad project that ended up 0:14:44.080 --> 0:14:50.560 excavating some ruins southeast of Baghdad, and they revealed what 0:14:50.760 --> 0:14:55.120 we have commonly referred to as the Bagdad batteries. These 0:14:55.160 --> 0:14:58.000 were vessels that appeared to have been designed specifically to 0:14:58.080 --> 0:15:02.800 generate electricity. At least that's one of the hypotheses about 0:15:02.840 --> 0:15:06.800 these these vessels. Some people disagree, but it's a very 0:15:06.800 --> 0:15:11.040 popular one. Now you probably have heard about this in 0:15:11.080 --> 0:15:13.400 some form of another or another. You may have even 0:15:13.480 --> 0:15:16.480 seen the MythBusters episode where they talked about this. The 0:15:16.560 --> 0:15:19.360 team in MythBusters talked about the possible applications for these 0:15:19.400 --> 0:15:23.160 so called batteries, which could include a thing that you 0:15:23.200 --> 0:15:26.360 would use in religious ceremonies, where you would have these 0:15:26.840 --> 0:15:31.200 metal coded vessels that if you were to touch them, 0:15:31.240 --> 0:15:34.360 you would create a circuit and you would allow electricity 0:15:34.400 --> 0:15:36.600 to flow through you, and that would create a tingling 0:15:36.720 --> 0:15:40.280 or numbing sensation in your hands, thus akin to some 0:15:40.360 --> 0:15:43.320 sort of mystical experience and thus being part of a 0:15:43.320 --> 0:15:47.640 religious experience. Or it could be that it was more 0:15:47.840 --> 0:15:54.320 of a practical approach toward something like electroplating, and I 0:15:54.360 --> 0:15:56.080 thought that was really cool. So let's talk about what 0:15:56.120 --> 0:15:59.720 electroplating is, because otherwise, you know, it doesn't really mean 0:15:59.760 --> 0:16:03.160 any thing to you. As the name implies, electro plating 0:16:03.160 --> 0:16:07.640 involves using electricity to cover or plate one material with 0:16:07.760 --> 0:16:12.520 another material. Typically you are plating one type of metal, 0:16:12.840 --> 0:16:15.800 not necessarily metal, but the early version of electro plating 0:16:15.880 --> 0:16:19.440 was metal, but one type of metal with a more 0:16:19.600 --> 0:16:23.600 precious metal. So the reason you might do this is 0:16:23.640 --> 0:16:28.600 to make really pretty expensive looking stuff without using too 0:16:28.680 --> 0:16:32.560 much of the actual precious material. So you might gold 0:16:32.560 --> 0:16:35.240 plate a copper bowl, for example, because you want the 0:16:35.240 --> 0:16:39.480 gold bowl. Gold is more precious than copper, but you 0:16:39.480 --> 0:16:41.280 don't want to actually have to go out and dig 0:16:41.400 --> 0:16:43.120 as much gold as you would need to build a 0:16:43.120 --> 0:16:45.960 gold bowl. So you want to plate the copper bowl 0:16:46.160 --> 0:16:49.840 with gold. That way, it looks exactly the way you 0:16:49.840 --> 0:16:52.280 want it to, but you didn't have to spend all 0:16:52.280 --> 0:16:54.600 that time and effort getting all that gold. In other words, 0:16:54.720 --> 0:16:57.840 we can thank the laziness and greed of human beings 0:16:57.880 --> 0:17:00.320 for some of the early advances as as far as 0:17:00.360 --> 0:17:06.000 electricity is concerned, So you might want to use electroplating 0:17:06.000 --> 0:17:08.920 to do that. We also use electroplating for other purposes, 0:17:09.000 --> 0:17:13.320 like putting rust resistant coatings onto stuff that otherwise would corrode. 0:17:14.440 --> 0:17:17.320 You can also use it to produce alloys like bronze 0:17:17.320 --> 0:17:22.000 and brass. But let's go back to electroplating. So let's 0:17:22.000 --> 0:17:25.200 say these ancient people were using the so called Baghdad 0:17:25.280 --> 0:17:29.000 batteries in order to electroplate gold onto copper. How would 0:17:29.000 --> 0:17:31.640 you do this, Well, first, you have to make sure 0:17:31.680 --> 0:17:34.520 that the copper is totally clean, because if it has 0:17:34.560 --> 0:17:38.479 any schmutz on it, the gold will not properly adhere 0:17:38.560 --> 0:17:42.280 to the copper and it'll flake off. So you typically 0:17:42.320 --> 0:17:46.679 would clean copper this way by dipping it in a 0:17:46.720 --> 0:17:51.000 solution that either is a really powerful alkaline solution or 0:17:51.040 --> 0:17:55.400 a very powerful acidic solution to truly clean it. Once 0:17:55.440 --> 0:17:58.400 you did that, you would then attach a conductor from 0:17:58.440 --> 0:18:02.919 the battery to the copper that you're playing on electroplating. 0:18:03.200 --> 0:18:05.040 So if it's a bowl, then you would want to 0:18:05.040 --> 0:18:09.040 make sure that the terminal, the proper terminal from the 0:18:09.119 --> 0:18:14.360 Bagdad battery is in contact with that copper bowl. Then 0:18:14.440 --> 0:18:17.760 you would put that whole thing, the copper bowl with 0:18:17.960 --> 0:18:23.320 the terminal into an electrolyte solution, which is in this 0:18:23.400 --> 0:18:27.720 case a gold based electrolyte, so you have gold particles 0:18:27.840 --> 0:18:31.639 within the electrolyte itself. Now, electrolytes, by the way, are 0:18:31.680 --> 0:18:36.320 materials that dissociate into ions when dissolved in a suitable medium, 0:18:36.359 --> 0:18:39.720 and become a conductor of electricity. So ions, of course 0:18:41.160 --> 0:18:45.240 our variations of atoms that have a net charge on them. 0:18:45.359 --> 0:18:47.760 They're not neutral. They have either a net negative or 0:18:47.800 --> 0:18:50.600 a net positive charge. So when you do this, you've 0:18:50.600 --> 0:18:55.480 got your gold ions in this electrolyte solution. You then 0:18:55.600 --> 0:18:59.440 put the electrodes together so that not together, but within 0:18:59.480 --> 0:19:02.320 the solution, and so that a current can pass through 0:19:03.200 --> 0:19:07.080 the electrodes. Allow the current to go through the electrolyte 0:19:07.119 --> 0:19:11.880 into the other terminal or the other electrode, and you've 0:19:11.880 --> 0:19:14.439 got a negative and a positive electrode. So when the 0:19:14.440 --> 0:19:17.199 current passes through the electrolyte, the electrolyte splits up and 0:19:17.240 --> 0:19:20.160 some of the metal atoms contained within the electrolyte are 0:19:20.160 --> 0:19:23.400 deposited on one of the two electrodes that you inserted 0:19:23.440 --> 0:19:26.200 into the electrolyte. So what's really happening is the metal 0:19:26.280 --> 0:19:28.879 atoms are ions. They hold that charge, they're attracted to 0:19:28.920 --> 0:19:32.040 the electrode that has the opposite charge and they attach 0:19:32.119 --> 0:19:36.600 to it. So if you have a negatively charged terminal 0:19:36.880 --> 0:19:40.920 and you have positively charged gold ions, that opposite attract 0:19:41.240 --> 0:19:44.560 rule still takes place, and the gold will plate onto 0:19:45.240 --> 0:19:50.920 the copper electrode or bowl in this case, and then 0:19:51.000 --> 0:19:53.760 you've got your gold plated copper thingam a jig, which 0:19:53.800 --> 0:19:56.560 is kind of cool. Now, there's some who put forth 0:19:56.560 --> 0:20:00.359 the hypothesis that perhaps ancient people's made other uses of 0:20:00.400 --> 0:20:04.199 electricity all the way up to even powering lights in 0:20:04.320 --> 0:20:11.280 ancient Egypt, but most scholars that I have consulted dismissed 0:20:11.320 --> 0:20:17.240 this as unrealistic. I haven't really seen much evidence to 0:20:17.280 --> 0:20:21.800 support this apart from some circumstantial evidence. Some supporters cite 0:20:21.840 --> 0:20:26.520 a hieroglyphic relief that shows what to our modern eyes 0:20:26.680 --> 0:20:30.240 appears to be an enormous light bulb. But the accepted 0:20:30.280 --> 0:20:34.520 interpretation of that hieroglyph seems to be that it's a 0:20:34.600 --> 0:20:37.239 lotus leaf with the figure of a snake on it, 0:20:37.680 --> 0:20:41.280 not a huge ancient light bulb. Still, it seems that 0:20:41.320 --> 0:20:43.800 there was at least some knowledge of the existence of electricity, 0:20:43.880 --> 0:20:46.679 if not what it actually could do or what it was. 0:20:48.200 --> 0:20:50.960 Now that's a trend that would last for centuries. In fact, 0:20:51.480 --> 0:20:54.880 we were making use of electricity well before anyone really 0:20:54.960 --> 0:20:57.199 knew what was going on with it. And again, to me, 0:20:57.359 --> 0:20:59.960 that is one of the phenomenal things about human history 0:21:00.080 --> 0:21:02.800 is when we come across these moments where people have 0:21:02.880 --> 0:21:06.240 figured out something or how to use something without really 0:21:06.240 --> 0:21:09.760 fully understanding why it is, that could be dangerous. Clearly, 0:21:10.240 --> 0:21:12.600 there were plenty of cases of that in the nineteen 0:21:12.680 --> 0:21:16.560 fifties with radiation, where people thought that radiation didn't have 0:21:16.600 --> 0:21:21.359 any particular harmful effects. You might have seen things about 0:21:21.400 --> 0:21:25.280 like using X rays in shoe stores so that people 0:21:25.320 --> 0:21:27.840 could see their feet through the shoes that they were 0:21:27.880 --> 0:21:31.399 trying on, and then only later did we realize that 0:21:31.640 --> 0:21:34.159 X rays are an ionizing form of radiation and that 0:21:34.240 --> 0:21:36.800 we probably should not or definitely should not have been 0:21:36.840 --> 0:21:40.080 doing that same sort of thing with electricity. We were 0:21:40.119 --> 0:21:42.439 putting it to use before we ever really understood what 0:21:42.520 --> 0:21:47.040 was going on there. But of course electricity isn't ionizing radiation, 0:21:47.160 --> 0:21:51.480 so it does have very different effects than radiation does. 0:21:52.560 --> 0:21:55.280 But what follows is a brief history of the developments 0:21:55.280 --> 0:21:58.719 that unfolded as very very smart people figured out what 0:21:58.760 --> 0:22:02.080 the heck electricity is. So in the fifteen hundreds you 0:22:02.160 --> 0:22:06.679 had an English physician and proto scientist named William Gilbert 0:22:06.960 --> 0:22:10.280 who began to experiment with magnets and static electricity. So 0:22:10.320 --> 0:22:14.800 he used loadstone, which is naturally magnetic iron ore, and 0:22:14.840 --> 0:22:18.040 he published his work in sixteen hundred under the title 0:22:18.600 --> 0:22:25.680 d Magnetae or Magnety. It's magneto but with a knee. 0:22:26.119 --> 0:22:30.000 He was able to describe magnetism and static electricity as 0:22:30.080 --> 0:22:33.080 distinct phenomena, though he wasn't really sure what was actually 0:22:33.080 --> 0:22:36.200 causing it. His hypothesis was that there was some sort 0:22:36.240 --> 0:22:40.199 of fluid or humor, as in the various humors of 0:22:40.240 --> 0:22:44.280 the body. There was another prevailing physical theory at the time, 0:22:44.600 --> 0:22:47.760 and that this was the cause of attraction with static electricity, 0:22:48.040 --> 0:22:50.199 and that if you rubbed amber, what you were actually 0:22:50.200 --> 0:22:53.359 doing was removing some of that fluid from the amber, 0:22:53.400 --> 0:22:57.480 which created a hole or like a vacuum around it, 0:22:57.520 --> 0:22:59.879 and this is why light objects would become a tra 0:23:00.240 --> 0:23:04.520 to the amber. He called it effluvium and described it 0:23:04.640 --> 0:23:10.600 as an electric effect. In sixteen sixty, an inventor named 0:23:10.640 --> 0:23:14.800 Auto von Geirica built a machine using a globe made 0:23:14.840 --> 0:23:17.879 of sulfur, and if you rubbed the globe as it turned, 0:23:17.920 --> 0:23:21.320 you could build up a charge, an electrostatic charge, causing 0:23:21.359 --> 0:23:23.840 it to attract small light objects, such as feathers or 0:23:23.880 --> 0:23:27.400 scraps of paper. Gherica also observed that his invention would 0:23:27.440 --> 0:23:30.640 cause a spark if you rubbed the globe for long enough. 0:23:30.680 --> 0:23:35.159 You could then touch something metal like a brass knob, 0:23:35.280 --> 0:23:39.800 and see a spark fly between the electrostatically charged object 0:23:39.840 --> 0:23:45.280 and the grounded piece of metal. Stephen Gray, another English scientist, 0:23:45.320 --> 0:23:48.440 observed in seventeen twenty nine that some stuff doesn't conduct 0:23:48.440 --> 0:23:51.720 electricity at all, so he thought some materials would allow 0:23:51.760 --> 0:23:56.359 the fluid of electricity to flow through, and other materials 0:23:56.359 --> 0:24:00.200 would hamper the flow of this fluid. Electricity would which 0:24:00.200 --> 0:24:03.200 is sort of true when you get to electrical resistance, 0:24:03.240 --> 0:24:07.560 only we're not talking about a fluid really. Later that century, 0:24:07.760 --> 0:24:13.640 Dutch inventor's Pietr von Mussen book and evolved von Kleist 0:24:14.119 --> 0:24:17.159 created what we now call the Leyden jar, and there 0:24:17.200 --> 0:24:21.280 are actually two variations on basic Leyden jars, which store 0:24:21.440 --> 0:24:25.399 electrostatic charges. They're essentially capacitors, So you build up an 0:24:25.440 --> 0:24:28.159 electric static charge in this thing, and then when you 0:24:29.320 --> 0:24:35.160 touch the the charged component, you allow that electrostatic charge 0:24:35.160 --> 0:24:40.600 to discharge to spark, so they release all of that 0:24:41.560 --> 0:24:45.679 charged energy in an instant. Unlike a battery, which releases 0:24:46.400 --> 0:24:51.760 uh well, which which creates the voltage difference and allows 0:24:51.760 --> 0:24:55.399 for electric electric current to flow over time, a capacitor 0:24:55.640 --> 0:25:00.199 releases it in a in a moment. The There are 0:25:00.200 --> 0:25:02.280 two basic versions of the Leaden jar, and the first 0:25:02.359 --> 0:25:07.200 one uses a metal container inside which you have a 0:25:07.240 --> 0:25:10.879 glass vessel nestled inside that metal container, and inside the 0:25:10.920 --> 0:25:15.800 glass vessel you have a second metal container nestled inside that. 0:25:15.840 --> 0:25:18.360 So it's kind of like a sandwich where the bread 0:25:18.680 --> 0:25:22.639 is metal container and the bread and the meat inside 0:25:22.800 --> 0:25:27.199 is glass. I don't recommend eating that sandwich, it would 0:25:27.440 --> 0:25:31.399 not taste good and probably hurt you. But it was 0:25:31.480 --> 0:25:36.639