1 00:00:04,400 --> 00:00:07,800 Speaker 1: Welcome to tech Stuff, a production from I Heart Radio. 2 00:00:12,119 --> 00:00:14,680 Speaker 1: Hey there, and welcome to tech Stuff. I'm your host, 3 00:00:14,840 --> 00:00:17,560 Speaker 1: Jonathan Strickland. I'm an executive producer with iHeart Radio and 4 00:00:17,600 --> 00:00:22,160 Speaker 1: I love all things tech and longtime listener and Tricks 5 00:00:22,320 --> 00:00:24,840 Speaker 1: wrote in on Twitter to ask if I had done 6 00:00:24,880 --> 00:00:30,520 Speaker 1: an episode on undersea cables, and you know what, I haven't. 7 00:00:31,320 --> 00:00:34,800 Speaker 1: So today we're going to start to talk about them, because, 8 00:00:34,840 --> 00:00:37,120 Speaker 1: as it turns out, there's a lot to cover with 9 00:00:37,280 --> 00:00:42,120 Speaker 1: undersea cables to kind of understand not just how they work, 10 00:00:42,400 --> 00:00:46,280 Speaker 1: but the challenges that people faced in order to make 11 00:00:46,360 --> 00:00:49,200 Speaker 1: them a reality in the first place. This is also 12 00:00:49,240 --> 00:00:53,280 Speaker 1: a timely topic because recently a company called x Links 13 00:00:53,720 --> 00:00:58,360 Speaker 1: made headlines for the Morocco UK power plant project. That 14 00:00:58,400 --> 00:01:01,080 Speaker 1: project's goal is to create a bowler and wind farm 15 00:01:01,160 --> 00:01:05,039 Speaker 1: in Morocco and use a very very long sub sea 16 00:01:05,319 --> 00:01:09,760 Speaker 1: power chord, essentially to send electricity to the UK. Now, 17 00:01:09,959 --> 00:01:12,840 Speaker 1: while a lot of headlines called this the longest subseed cable, 18 00:01:13,240 --> 00:01:16,880 Speaker 1: that's misleading because there are actually many different types of cables, 19 00:01:17,400 --> 00:01:22,399 Speaker 1: and technically the ce ME WE three cable that's s 20 00:01:22,440 --> 00:01:26,200 Speaker 1: E A dash M E dash W E three, the 21 00:01:26,280 --> 00:01:30,080 Speaker 1: number three cable is actually about ten times longer than 22 00:01:30,120 --> 00:01:33,679 Speaker 1: what the Morocco UK cable will be. But we're gonna 23 00:01:33,720 --> 00:01:36,920 Speaker 1: get to all that probably in the next episode, definitely 24 00:01:37,000 --> 00:01:40,200 Speaker 1: not this one. But as and Tricks pointed out in 25 00:01:40,240 --> 00:01:42,880 Speaker 1: a tweet to me, undersea cables trace their history back 26 00:01:42,920 --> 00:01:47,000 Speaker 1: to the mid nineteenth century. So in order to understand 27 00:01:47,040 --> 00:01:49,279 Speaker 1: all of this, we really have to take a moment 28 00:01:49,320 --> 00:01:52,360 Speaker 1: and talk about the telegraph and the development of the 29 00:01:52,440 --> 00:01:55,800 Speaker 1: first undersea cables. So there were a few things that 30 00:01:55,880 --> 00:01:59,800 Speaker 1: had to happen for undersea cables to even become a necessity. 31 00:02:00,320 --> 00:02:02,480 Speaker 1: You know. One of those was the development of the 32 00:02:02,480 --> 00:02:06,520 Speaker 1: electric telegraph, because without that, there's no need to worry 33 00:02:06,560 --> 00:02:09,440 Speaker 1: about subsea cables. Right, If you don't have long distance 34 00:02:09,520 --> 00:02:13,200 Speaker 1: electric based communication, then cables aren't really a thing you 35 00:02:13,280 --> 00:02:16,839 Speaker 1: gotta worry about, at least as far as connecting, say 36 00:02:16,919 --> 00:02:21,880 Speaker 1: an island to a continent. Now, the word telegraph is 37 00:02:21,960 --> 00:02:27,240 Speaker 1: Greek and it means essentially distant writing. But this word 38 00:02:27,280 --> 00:02:33,079 Speaker 1: actually predates electric telegraphs. For example, there were semaphore systems, 39 00:02:33,320 --> 00:02:37,040 Speaker 1: ones that used visual cues with flags. Those were used 40 00:02:37,120 --> 00:02:40,440 Speaker 1: throughout France, and we're really developed during the Napoleonic wars, 41 00:02:41,120 --> 00:02:45,040 Speaker 1: and that was referred to as telegraph. Before any kind 42 00:02:45,040 --> 00:02:48,200 Speaker 1: of electric version came along in the late seventeen hundreds, 43 00:02:48,560 --> 00:02:52,440 Speaker 1: you had various smarty pants around the world experimenting with electricity, 44 00:02:53,080 --> 00:02:56,280 Speaker 1: you know, like Ben Franklin, and this was just something 45 00:02:56,320 --> 00:02:58,760 Speaker 1: that was just beginning to be understood at the time. 46 00:02:59,240 --> 00:03:03,400 Speaker 1: Alissandre of Volta had created a sort of proto battery 47 00:03:03,440 --> 00:03:06,399 Speaker 1: that we later called a voltaic pile or and then 48 00:03:06,560 --> 00:03:10,240 Speaker 1: later on we had the voltaic cells. These inventions could 49 00:03:10,240 --> 00:03:14,160 Speaker 1: produce a good electric current, but at a very low voltage. 50 00:03:14,280 --> 00:03:16,880 Speaker 1: Now we need a reminder here because we're gonna be 51 00:03:16,880 --> 00:03:21,520 Speaker 1: talking about electricity a lot. Voltage in electricity is sort 52 00:03:21,520 --> 00:03:24,799 Speaker 1: of similar to water pressure in a plumbing system. You 53 00:03:24,840 --> 00:03:28,240 Speaker 1: can think of it as how much oomph a current has, 54 00:03:28,840 --> 00:03:32,160 Speaker 1: and current you can think of as the amount of 55 00:03:32,240 --> 00:03:39,360 Speaker 1: electricity present in a system of flowing electricity or flowing electrons. So, 56 00:03:40,160 --> 00:03:42,760 Speaker 1: if we want a really quick analogy, if you had 57 00:03:42,800 --> 00:03:47,040 Speaker 1: a low voltage, high current source of electricity, that's kind 58 00:03:47,040 --> 00:03:50,040 Speaker 1: of like a lazy river, right. The river can be 59 00:03:50,120 --> 00:03:52,640 Speaker 1: really wide and it might be really deep, so you've 60 00:03:52,640 --> 00:03:55,160 Speaker 1: got a lot of water there, but that water isn't 61 00:03:55,240 --> 00:04:00,480 Speaker 1: moving very quickly. It's just lazily going down. A high voltage, 62 00:04:00,680 --> 00:04:06,360 Speaker 1: low current electric device produces a very tight, high pressured stream. 63 00:04:06,480 --> 00:04:10,400 Speaker 1: So think of like a a concentrated stream of water 64 00:04:10,480 --> 00:04:13,880 Speaker 1: coming out of a pressure hose. You don't it's not 65 00:04:14,000 --> 00:04:16,839 Speaker 1: nearly the same amount of water as the lazy river. 66 00:04:17,080 --> 00:04:20,800 Speaker 1: It's much less current in other words, but the pressure 67 00:04:21,320 --> 00:04:27,520 Speaker 1: or voltage is way higher. Well before Volta's discovery, scientists 68 00:04:27,520 --> 00:04:30,840 Speaker 1: and engineers were mostly reliant on devices that would build 69 00:04:30,920 --> 00:04:35,039 Speaker 1: up electrostatic charges. So electro static charges have a high 70 00:04:35,120 --> 00:04:39,080 Speaker 1: voltage but a low current, and they have limited applicability 71 00:04:39,640 --> 00:04:43,320 Speaker 1: in things where you need sustained electric current. So Volta's 72 00:04:43,480 --> 00:04:48,440 Speaker 1: invention would allow for new applications of electricity. Now in 73 00:04:48,480 --> 00:04:51,800 Speaker 1: the early eighteen hundreds you had some other smarty pants 74 00:04:51,839 --> 00:04:56,120 Speaker 1: like Hans Christian Orstead of Denmark. And by the way, 75 00:04:56,600 --> 00:05:00,360 Speaker 1: as always, my apologies for all the mispronunciation, and I'm 76 00:05:00,360 --> 00:05:03,080 Speaker 1: going to do of all the different names that is 77 00:05:03,120 --> 00:05:07,720 Speaker 1: on me and I apologize. However, he discovered that electricity 78 00:05:07,760 --> 00:05:11,880 Speaker 1: and magnetism have a connection. He observed that a magnetic 79 00:05:11,960 --> 00:05:17,279 Speaker 1: needle would deflect from magnetic north if it came close 80 00:05:17,320 --> 00:05:20,400 Speaker 1: to a wire that was carrying an electric current or 81 00:05:20,480 --> 00:05:24,039 Speaker 1: transmitting an electric current, and so we first began to 82 00:05:24,080 --> 00:05:27,680 Speaker 1: realize that electro magnetism is a thing, that there is 83 00:05:27,760 --> 00:05:33,200 Speaker 1: this relationship between electricity and magnetism. This would lead to 84 00:05:33,480 --> 00:05:36,080 Speaker 1: yet more smarty pants people thinking of ways that we 85 00:05:36,120 --> 00:05:41,320 Speaker 1: could use electricity through wires to communicate across vast distances. 86 00:05:42,000 --> 00:05:45,359 Speaker 1: One way, a way that Sir William Father gil Cook 87 00:05:45,600 --> 00:05:50,280 Speaker 1: and Sir Charles Wheatston suggested was to have a multi 88 00:05:50,320 --> 00:05:55,240 Speaker 1: wire system that would use up to five needles. They 89 00:05:55,279 --> 00:05:59,000 Speaker 1: experiment with different ones, but the one that they would 90 00:05:59,080 --> 00:06:03,279 Speaker 1: use heavily would have five needle pointers, and that would 91 00:06:03,320 --> 00:06:06,120 Speaker 1: be at the receiving end of this system. So you 92 00:06:06,120 --> 00:06:09,880 Speaker 1: could send different electrical signals down these different wires and 93 00:06:09,920 --> 00:06:13,960 Speaker 1: thus direct these needles these pointers to point to different 94 00:06:14,120 --> 00:06:18,680 Speaker 1: letters on a placard that would have the alphabet there. 95 00:06:19,160 --> 00:06:21,240 Speaker 1: Uh The system would remain in use in the UK 96 00:06:21,480 --> 00:06:24,760 Speaker 1: up through the early twentieth century, so the UK was 97 00:06:24,800 --> 00:06:27,479 Speaker 1: reliant on this system, whereas the rest of the world 98 00:06:27,520 --> 00:06:30,400 Speaker 1: would move on to other ones. The neat thing about 99 00:06:30,400 --> 00:06:33,240 Speaker 1: the system is that it arranged the alphabet in a 100 00:06:33,360 --> 00:06:37,960 Speaker 1: diamond pattern, so it only used twenty letters of the alphabet. 101 00:06:38,000 --> 00:06:42,400 Speaker 1: It left out the letters C, J, Q, U, X, 102 00:06:42,440 --> 00:06:44,800 Speaker 1: and z, so sometimes you had to do, you know, 103 00:06:46,040 --> 00:06:50,040 Speaker 1: approximations of certain words. And the letter A was at 104 00:06:50,080 --> 00:06:52,600 Speaker 1: the top point of the diamond, and then you know, 105 00:06:52,640 --> 00:06:54,840 Speaker 1: you had B and D at the next level, and 106 00:06:54,880 --> 00:06:56,479 Speaker 1: then so on and so forth, and then at the 107 00:06:56,520 --> 00:07:00,360 Speaker 1: bottom you had the letter Y. And the five needles 108 00:07:00,360 --> 00:07:03,000 Speaker 1: were split right in the middle of this diamond. They 109 00:07:03,000 --> 00:07:05,760 Speaker 1: were in the widest part of the diamond, pointing up 110 00:07:05,800 --> 00:07:07,880 Speaker 1: and down normally, which meant that they weren't pointing at 111 00:07:07,880 --> 00:07:12,560 Speaker 1: any specific letter. So by sending signals down specific wires, 112 00:07:13,000 --> 00:07:16,000 Speaker 1: you could make needles point to a specific letter. You 113 00:07:16,040 --> 00:07:18,360 Speaker 1: would have both of you know, two needles that were 114 00:07:18,360 --> 00:07:22,640 Speaker 1: on a diagonal line with a specific letter, and by 115 00:07:22,760 --> 00:07:26,040 Speaker 1: looking at the common letter that both needles were pointing at, 116 00:07:26,360 --> 00:07:30,120 Speaker 1: you could spell out words. An interesting approach, not necessarily 117 00:07:30,160 --> 00:07:33,640 Speaker 1: the fastest, but it worked. Later on, Wheatstone would create 118 00:07:33,680 --> 00:07:37,560 Speaker 1: a different system that had a circular dial uh than 119 00:07:37,640 --> 00:07:40,480 Speaker 1: a needle on the inside, and you had the alphabet 120 00:07:40,560 --> 00:07:43,720 Speaker 1: laid out along the inside circumference of the circle, so 121 00:07:43,840 --> 00:07:47,000 Speaker 1: sort of like an analog clock, except instead of numbers 122 00:07:47,080 --> 00:07:49,960 Speaker 1: for the time, you had the alphabet, and you also 123 00:07:50,000 --> 00:07:53,360 Speaker 1: could have numbers as well. Then you had keys that 124 00:07:53,400 --> 00:07:56,360 Speaker 1: matched the letters and numbers that were along the outside 125 00:07:56,400 --> 00:07:59,120 Speaker 1: of the style. So pressing down on a key would indicate, Okay, 126 00:07:59,200 --> 00:08:02,560 Speaker 1: I want to send this letter UM, and this is 127 00:08:02,600 --> 00:08:04,840 Speaker 1: the sending station, And then you would have a receiving 128 00:08:04,840 --> 00:08:06,920 Speaker 1: station on the other end that would have a similar 129 00:08:06,960 --> 00:08:09,720 Speaker 1: dial with a needle and the letters and numbers in it, 130 00:08:10,200 --> 00:08:13,280 Speaker 1: and pressing down a specific key would end up sending 131 00:08:13,280 --> 00:08:15,520 Speaker 1: a signal that would have the needle on the other 132 00:08:15,560 --> 00:08:19,640 Speaker 1: side point to the relevant letter or number. This way 133 00:08:20,120 --> 00:08:22,720 Speaker 1: was really neat and the way it worked is super cool. 134 00:08:23,120 --> 00:08:25,200 Speaker 1: But I'm gonna have to save that for another episode 135 00:08:25,200 --> 00:08:28,880 Speaker 1: because I'm supposed to focus on subsei cables, and I 136 00:08:28,920 --> 00:08:31,280 Speaker 1: wrote about a page and a half of stuff before 137 00:08:31,320 --> 00:08:33,960 Speaker 1: I realized I am getting way off track, so I'll 138 00:08:33,960 --> 00:08:36,240 Speaker 1: spare you for now, but that will come up maybe 139 00:08:36,280 --> 00:08:39,880 Speaker 1: in a future episode. Now, in America, it was Samuel Morse, 140 00:08:39,920 --> 00:08:43,640 Speaker 1: who interestingly was an art professor who came up with 141 00:08:43,679 --> 00:08:47,840 Speaker 1: the famous method for transmitting messages electrically using a special code, 142 00:08:48,480 --> 00:08:51,080 Speaker 1: one that today, of course, we refer to as the 143 00:08:51,160 --> 00:08:55,640 Speaker 1: Samuel Code. Don't wait no, I'm sorry. No. Morse code. 144 00:08:55,880 --> 00:09:00,319 Speaker 1: Morse code. Morse code uses dots and dashes to rep 145 00:09:00,440 --> 00:09:04,000 Speaker 1: letters and numbers, and by tapping the dots and dashes 146 00:09:04,080 --> 00:09:07,120 Speaker 1: on a telegraph key, you could send pulses of electrical 147 00:09:07,200 --> 00:09:09,760 Speaker 1: signal down a wire, and a receiver at the other 148 00:09:09,840 --> 00:09:13,120 Speaker 1: end could then emboss dots and dashes on a strip 149 00:09:13,160 --> 00:09:15,439 Speaker 1: of paper, so you could actually read out the dots 150 00:09:15,440 --> 00:09:18,480 Speaker 1: and dashes and translate it that way, or later on 151 00:09:18,920 --> 00:09:23,079 Speaker 1: you had engineers who are trained to listen for dots 152 00:09:23,080 --> 00:09:25,840 Speaker 1: and dashes, and you had a device that was essentially 153 00:09:25,840 --> 00:09:30,400 Speaker 1: tapping like a little anvil, tapping out the messages, and 154 00:09:30,400 --> 00:09:33,720 Speaker 1: you would just listen. Later, a guy named Alfred Vale 155 00:09:33,720 --> 00:09:36,360 Speaker 1: would partner with Morse to refine this system and make 156 00:09:36,400 --> 00:09:39,880 Speaker 1: it a little more practical, essentially looking at the most 157 00:09:40,200 --> 00:09:45,360 Speaker 1: frequently used letters and using the the simplest dots and 158 00:09:45,440 --> 00:09:48,720 Speaker 1: dash patterns to represent those letters, as well as to 159 00:09:48,840 --> 00:09:53,400 Speaker 1: redesign the telegraph key itself. By eighteen thirty seven, Veil 160 00:09:53,480 --> 00:09:56,720 Speaker 1: and Morse were demonstrating this technology, and by eighteen forty 161 00:09:56,800 --> 00:10:00,640 Speaker 1: three they secured funding to set up an experiment telegraph 162 00:10:00,679 --> 00:10:04,040 Speaker 1: line that stretched the thirty five miles around sixty kilometers 163 00:10:04,440 --> 00:10:08,280 Speaker 1: between Baltimore, Maryland and Washington, d c Here in America. 164 00:10:08,920 --> 00:10:13,240 Speaker 1: The project used poles that were erected alongside a railroad 165 00:10:13,320 --> 00:10:17,320 Speaker 1: line and wires connected to the poles via glass insulators, 166 00:10:17,400 --> 00:10:21,600 Speaker 1: and it worked. One thing that really amazed me as 167 00:10:21,600 --> 00:10:24,400 Speaker 1: I was doing research into this, just as a quick digression, 168 00:10:25,000 --> 00:10:29,600 Speaker 1: is how quickly things moved. Because this was eight three, 169 00:10:30,080 --> 00:10:33,400 Speaker 1: and we're gonna be talking about a transatlantic subsea cable 170 00:10:33,440 --> 00:10:37,000 Speaker 1: by the end of this episode. That came a little 171 00:10:37,040 --> 00:10:40,200 Speaker 1: more than a decade after that. And to think of 172 00:10:40,240 --> 00:10:42,680 Speaker 1: it being ten years, a little more than ten years 173 00:10:42,720 --> 00:10:47,000 Speaker 1: between stringing sixty kilometers of cable between two cities in 174 00:10:47,040 --> 00:10:51,760 Speaker 1: America to laying a subsea cable across the Atlantic Ocean 175 00:10:52,480 --> 00:10:56,800 Speaker 1: blows my mind. Well, anyway, the demonstration was a success, 176 00:10:56,880 --> 00:10:59,199 Speaker 1: and it didn't take long for railroad companies to start 177 00:10:59,280 --> 00:11:02,240 Speaker 1: building out tell alegraph systems, and early on they were 178 00:11:02,280 --> 00:11:05,440 Speaker 1: almost exclusively used to help keep track of traffic on 179 00:11:05,480 --> 00:11:07,880 Speaker 1: the rail system, to better plan out routes, and to 180 00:11:07,960 --> 00:11:11,080 Speaker 1: avoid long delays or accidents. By the end of the 181 00:11:11,080 --> 00:11:13,960 Speaker 1: eighteen forties, journalists were starting to make use of the 182 00:11:13,960 --> 00:11:18,720 Speaker 1: telegraph system to wire stories across vast distances, and businesses 183 00:11:18,760 --> 00:11:21,520 Speaker 1: began to get interested in this as well, the ability 184 00:11:21,600 --> 00:11:24,920 Speaker 1: to be able to conduct business between cities without having 185 00:11:25,000 --> 00:11:29,120 Speaker 1: to take you know, a train ride or otherwise have 186 00:11:29,400 --> 00:11:33,120 Speaker 1: you know, like like people on horseback travel from one 187 00:11:33,160 --> 00:11:35,760 Speaker 1: city to another. Because keep in mind this is this 188 00:11:35,840 --> 00:11:39,959 Speaker 1: is before the automobile has really become a thing. So yeah, 189 00:11:40,000 --> 00:11:43,000 Speaker 1: there were limited ways of getting information from one point 190 00:11:43,000 --> 00:11:47,720 Speaker 1: to another. However, until eighteen fifty, these distances were all 191 00:11:47,720 --> 00:11:52,520 Speaker 1: over land. The reach of telegraph systems ended at the coastlines, 192 00:11:53,080 --> 00:11:56,760 Speaker 1: which meant that while regions could develop a sophisticated internal 193 00:11:56,800 --> 00:12:01,319 Speaker 1: communications system you know, inside their border or maybe between 194 00:12:01,440 --> 00:12:05,840 Speaker 1: borders of neighboring nations that shared you know, a land border, 195 00:12:05,960 --> 00:12:08,720 Speaker 1: once you hit the ocean, you had to rely on 196 00:12:08,840 --> 00:12:13,800 Speaker 1: other methods, much slower methods. So a mail ship isn't 197 00:12:13,840 --> 00:12:17,839 Speaker 1: a ship that carries mail, not a not a gendered ship, 198 00:12:18,280 --> 00:12:21,480 Speaker 1: but a mail ship between London and New York could 199 00:12:21,480 --> 00:12:24,560 Speaker 1: take nearly a month to travel across the ocean. A 200 00:12:24,640 --> 00:12:26,520 Speaker 1: fast one might be able to make the journey in 201 00:12:26,679 --> 00:12:31,199 Speaker 1: three weeks. By the mid nineteenth century, steamships were largely 202 00:12:31,240 --> 00:12:33,439 Speaker 1: taking the place of sailing vessels. They could make the 203 00:12:33,520 --> 00:12:36,920 Speaker 1: journey in up around ten days, so still more than 204 00:12:36,960 --> 00:12:40,079 Speaker 1: a week to get from one point to another. That's 205 00:12:40,280 --> 00:12:44,400 Speaker 1: pretty slow for news to travel. It was difficult to 206 00:12:44,480 --> 00:12:48,959 Speaker 1: act with alacrity if you were relying upon information from 207 00:12:49,000 --> 00:12:53,120 Speaker 1: across the pond. So there was a strong use case 208 00:12:53,520 --> 00:12:57,800 Speaker 1: to make for creating an undersea cable infrastructure that could 209 00:12:57,840 --> 00:13:00,680 Speaker 1: connect distant parts of the world, you know, parts that 210 00:13:00,720 --> 00:13:04,600 Speaker 1: were separated by oceans, and even in Europe, like England 211 00:13:04,880 --> 00:13:08,439 Speaker 1: in particular, saw the need to do this because while 212 00:13:08,960 --> 00:13:11,800 Speaker 1: the distance was not nearly as great to travel from 213 00:13:11,880 --> 00:13:17,439 Speaker 1: say Dover to France, the delay in getting information from 214 00:13:17,440 --> 00:13:19,959 Speaker 1: other parts of Europe was still pretty considerable, so there 215 00:13:20,040 --> 00:13:23,480 Speaker 1: was definitely a need for that as well. This did, however, 216 00:13:23,559 --> 00:13:27,080 Speaker 1: present some engineering challenges because you had to find a 217 00:13:27,120 --> 00:13:31,720 Speaker 1: way to make this both practical and affordable. Now this 218 00:13:31,800 --> 00:13:34,199 Speaker 1: is going to be obvious, but I need to establish it. 219 00:13:34,200 --> 00:13:38,040 Speaker 1: It is way easier to repair and maintain infrastructure that's 220 00:13:38,040 --> 00:13:41,400 Speaker 1: above the water than it is to do below the water. 221 00:13:41,840 --> 00:13:46,400 Speaker 1: And that's because we live above the water and we 222 00:13:46,480 --> 00:13:48,880 Speaker 1: can't live below the water, at least not with the 223 00:13:48,920 --> 00:13:52,079 Speaker 1: same amount of freedom. And since the Mr folks seemed 224 00:13:52,160 --> 00:13:56,200 Speaker 1: completely uninterested in helping us maintain communication channels. We have 225 00:13:56,280 --> 00:13:59,440 Speaker 1: to take that into consideration. To that end, we have 226 00:13:59,480 --> 00:14:04,600 Speaker 1: to treat cables subseed cables different from terrestrial cables. We 227 00:14:04,640 --> 00:14:07,679 Speaker 1: have to take into consideration what being submersed in ocean 228 00:14:07,720 --> 00:14:10,480 Speaker 1: water is going to do to a cable over time. 229 00:14:10,760 --> 00:14:14,800 Speaker 1: We have to understand that those effects can be detrimental. 230 00:14:14,840 --> 00:14:16,800 Speaker 1: We have to be able to estimate how long a 231 00:14:16,840 --> 00:14:21,400 Speaker 1: particular cable is likely to remain viable, assuming no catastrophic 232 00:14:21,440 --> 00:14:25,640 Speaker 1: instances occur, like assuming that a ship's anchor doesn't tear 233 00:14:25,680 --> 00:14:28,000 Speaker 1: through the cable, for example. So we have to make 234 00:14:28,040 --> 00:14:31,040 Speaker 1: sure that we have the budget to not just install 235 00:14:31,080 --> 00:14:34,920 Speaker 1: a cable in the first place, but to potentially replace 236 00:14:35,040 --> 00:14:39,040 Speaker 1: that cable when we near the end of its estimated lifespan. 237 00:14:39,560 --> 00:14:42,800 Speaker 1: It has to make financial sense, or else it's a 238 00:14:42,840 --> 00:14:46,400 Speaker 1: loss in the long run. Right. So you can argue, yes, 239 00:14:46,480 --> 00:14:52,320 Speaker 1: it's invaluable to have two distant places connected together, but 240 00:14:52,400 --> 00:14:57,080 Speaker 1: if you're constantly having to replace the communication channel, then 241 00:14:57,360 --> 00:15:01,040 Speaker 1: that invaluable might start to take on of value where 242 00:15:01,040 --> 00:15:03,760 Speaker 1: you just say, yeah, it's invaluable, but I don't want 243 00:15:03,760 --> 00:15:06,240 Speaker 1: to pay for it. So coming up with a way 244 00:15:06,280 --> 00:15:10,080 Speaker 1: to make subsea cables work extends beyond just the technology. 245 00:15:10,920 --> 00:15:13,400 Speaker 1: I mean, obviously the tech is a critical component or 246 00:15:13,400 --> 00:15:18,360 Speaker 1: else nothing happens. But you can't ignore the financial element, 247 00:15:18,560 --> 00:15:22,360 Speaker 1: right or the physical challenges, because if you do that, 248 00:15:22,440 --> 00:15:26,360 Speaker 1: you're setting yourself out to fail. So we're gonna take 249 00:15:26,400 --> 00:15:28,160 Speaker 1: a quick break. But when we come back, we're gonna 250 00:15:28,200 --> 00:15:31,760 Speaker 1: talk about a couple of other things before we get 251 00:15:31,800 --> 00:15:36,200 Speaker 1: to the first subseed cable, like some basic things about 252 00:15:36,520 --> 00:15:40,360 Speaker 1: electrical transmission. But before we do that, let's take this 253 00:15:40,440 --> 00:15:51,360 Speaker 1: quick break. All right, So in the eighteen twenties and 254 00:15:51,440 --> 00:15:55,000 Speaker 1: eighteen thirties you had all these various smarty pants is 255 00:15:55,400 --> 00:15:58,680 Speaker 1: is all learning about electro magnetism. And we now know 256 00:15:59,040 --> 00:16:02,440 Speaker 1: that if you pass an electric current through a conductive material, 257 00:16:03,160 --> 00:16:06,960 Speaker 1: that generates a magnetic field. And similarly, should you have 258 00:16:07,120 --> 00:16:10,800 Speaker 1: a conductive material like a wire, encounter a magnetic field, 259 00:16:11,240 --> 00:16:14,720 Speaker 1: that field will induce an electric current to flow through 260 00:16:15,040 --> 00:16:19,080 Speaker 1: the conductive wire. And you've probably played with this in school, 261 00:16:19,200 --> 00:16:21,920 Speaker 1: making a simple electro magnet with like an iron nail, 262 00:16:22,120 --> 00:16:24,920 Speaker 1: some copper wire, and a battery. You know, you connect 263 00:16:25,000 --> 00:16:28,840 Speaker 1: the wire to either terminal of the battery, you've coiled 264 00:16:28,840 --> 00:16:32,760 Speaker 1: the wire around the nail to act as a core, 265 00:16:33,200 --> 00:16:35,320 Speaker 1: and it becomes magnetic. You can pick up paper clips 266 00:16:35,320 --> 00:16:37,640 Speaker 1: and stuff. I remember I did that in school. I 267 00:16:37,640 --> 00:16:41,520 Speaker 1: imagined that people still do well. There's a whole lot 268 00:16:41,520 --> 00:16:44,320 Speaker 1: more to electro magnets, but we're just going to focus 269 00:16:44,360 --> 00:16:48,080 Speaker 1: on a couple of little things first. And the first 270 00:16:48,120 --> 00:16:52,640 Speaker 1: important bit is, because of this relationship between electricity and magnetism, 271 00:16:52,720 --> 00:16:55,160 Speaker 1: we need to make sure that wires and cables that 272 00:16:55,200 --> 00:16:59,400 Speaker 1: we use to transmit electricity have really good insulation around them. 273 00:16:59,440 --> 00:17:02,880 Speaker 1: And that's because us Without insulation, that is, without some 274 00:17:02,960 --> 00:17:06,959 Speaker 1: sort of barrier that resists the flow of electricity and 275 00:17:07,000 --> 00:17:11,200 Speaker 1: the interaction of magnetic fields, you have the potential for interference. 276 00:17:11,560 --> 00:17:14,920 Speaker 1: So let's say you've got two copper cables and there's 277 00:17:14,920 --> 00:17:18,480 Speaker 1: no shielding on them, you don't have any insulation on them, 278 00:17:18,560 --> 00:17:20,719 Speaker 1: and you've got them close to each other. And then 279 00:17:20,800 --> 00:17:24,760 Speaker 1: let's say you send electricity through one of those two cables, 280 00:17:24,760 --> 00:17:28,440 Speaker 1: not the second one, just cable number one. Well, as 281 00:17:28,440 --> 00:17:32,000 Speaker 1: the electricity flows through cable number one, that creates a 282 00:17:32,040 --> 00:17:35,600 Speaker 1: magnetic field which overlaps to the second cable, and that 283 00:17:35,640 --> 00:17:38,680 Speaker 1: induces a current to flow Now, if we're using direct 284 00:17:38,760 --> 00:17:42,880 Speaker 1: current something like a battery, uh, the second cable will 285 00:17:42,920 --> 00:17:46,480 Speaker 1: only have electric current running at the very beginning when 286 00:17:46,520 --> 00:17:50,320 Speaker 1: that magnetic field first hits it, but then it will stop. However, 287 00:17:50,640 --> 00:17:54,439 Speaker 1: if the source is alternating current then which means that 288 00:17:54,480 --> 00:17:58,000 Speaker 1: the current is changing direction many times per second, then 289 00:17:58,080 --> 00:18:00,520 Speaker 1: what you have is a fluctuating magnet at it field. 290 00:18:00,520 --> 00:18:04,359 Speaker 1: Because the magnetic fields direction also changes many times per second, 291 00:18:04,880 --> 00:18:07,800 Speaker 1: that will continue to induce electricity to flow in the 292 00:18:08,000 --> 00:18:12,480 Speaker 1: second cable. This would be in interference. It creates phantom 293 00:18:12,560 --> 00:18:16,800 Speaker 1: signals when no signal is intended, or it interferes as 294 00:18:16,800 --> 00:18:22,960 Speaker 1: one signal overpowers or changes another. I remember back in 295 00:18:23,000 --> 00:18:26,119 Speaker 1: the day, I had these cheap desktop speakers that I 296 00:18:26,160 --> 00:18:28,520 Speaker 1: had connected to my computer, and I would put my 297 00:18:28,560 --> 00:18:32,160 Speaker 1: cell phone down on the desk, and every time my 298 00:18:32,320 --> 00:18:37,160 Speaker 1: cell phone got a notification, it would make this weird 299 00:18:37,240 --> 00:18:42,199 Speaker 1: electric chirping noise in the speakers because that was radio 300 00:18:42,240 --> 00:18:47,200 Speaker 1: frequency interference that was inducing a current to flow through 301 00:18:47,240 --> 00:18:50,600 Speaker 1: the speakers. So these are things that can happen, and 302 00:18:50,640 --> 00:18:53,040 Speaker 1: you don't want them to write. You want to shield 303 00:18:53,840 --> 00:18:57,520 Speaker 1: your components so that only the signals you want to 304 00:18:57,600 --> 00:18:59,920 Speaker 1: send are going through so you have to protect a 305 00:19:00,000 --> 00:19:03,600 Speaker 1: against that. Now, in the nineteenth century, there were people 306 00:19:03,640 --> 00:19:08,080 Speaker 1: who discovered a plant that had a kind of sap 307 00:19:08,160 --> 00:19:10,719 Speaker 1: essentially that was found to be a really effective insulator, 308 00:19:11,160 --> 00:19:14,280 Speaker 1: so it resisted the flow electricity and protects or insulates 309 00:19:14,280 --> 00:19:18,600 Speaker 1: against interference. That material is called Gutta percha. It's a 310 00:19:18,720 --> 00:19:22,959 Speaker 1: biologically derived latex. And like I said, the plant has 311 00:19:23,000 --> 00:19:25,600 Speaker 1: the name Gutta percha, but that's also the name everyone 312 00:19:25,720 --> 00:19:31,240 Speaker 1: used for the derived latex from it. Now, this was 313 00:19:31,359 --> 00:19:34,439 Speaker 1: fortunate at the time, but I should also add that 314 00:19:34,480 --> 00:19:38,280 Speaker 1: the telecommunications industry would spell doom for the Gutta purchase 315 00:19:38,320 --> 00:19:41,520 Speaker 1: trees because the rampant harvesting of the trees created an 316 00:19:41,600 --> 00:19:47,639 Speaker 1: unsustainable situation. And before too long people realize, oh, we 317 00:19:47,680 --> 00:19:50,679 Speaker 1: need an alternative to this, because pretty soon there's not 318 00:19:50,720 --> 00:19:52,679 Speaker 1: going to be any of this plant left on the 319 00:19:52,720 --> 00:19:56,920 Speaker 1: planet will have harvested at all. Anyway, Gutta percha has 320 00:19:57,160 --> 00:20:00,960 Speaker 1: many of the same properties as synthetic rubber, including the 321 00:20:00,960 --> 00:20:04,920 Speaker 1: ability to insulate conductive materials. Next, we need to think 322 00:20:04,960 --> 00:20:08,000 Speaker 1: about what happens with electricity as it travels over greater 323 00:20:08,119 --> 00:20:11,920 Speaker 1: distances of wire um. This is going to get more 324 00:20:11,960 --> 00:20:15,080 Speaker 1: complicated later in this episode, because, as it turns out, 325 00:20:15,880 --> 00:20:17,520 Speaker 1: there are certain things that we have to take into 326 00:20:17,560 --> 00:20:20,479 Speaker 1: consideration with any length of cable, and then there are 327 00:20:20,480 --> 00:20:23,240 Speaker 1: other things that come into play when you're talking about 328 00:20:23,280 --> 00:20:26,480 Speaker 1: cable that happens to be under the water. But under 329 00:20:26,480 --> 00:20:31,240 Speaker 1: most circumstances, even a great electrical conductor has some level 330 00:20:31,320 --> 00:20:34,639 Speaker 1: of resistance. Now I say under most circumstances, because as 331 00:20:34,680 --> 00:20:39,720 Speaker 1: it turns out, if you're able to super cool a conductor, 332 00:20:40,080 --> 00:20:42,199 Speaker 1: like a good conductor, and you're able to get it 333 00:20:42,240 --> 00:20:45,840 Speaker 1: down to an incredibly low temperature, like just a few 334 00:20:46,320 --> 00:20:50,439 Speaker 1: units of kelvin above absolute zero, then you can have 335 00:20:50,480 --> 00:20:55,159 Speaker 1: a superconductor which has no resistance. But under most normal conditions, 336 00:20:55,440 --> 00:20:58,360 Speaker 1: you know, conductors have resistance to electricity. You can think 337 00:20:58,359 --> 00:21:01,640 Speaker 1: of electrical resistance as kind of being like friction. It's 338 00:21:01,680 --> 00:21:06,680 Speaker 1: working against or resisting the flow of electricity. So resistance 339 00:21:06,720 --> 00:21:11,040 Speaker 1: depends upon a few different factors, such as the material itself, 340 00:21:11,080 --> 00:21:13,439 Speaker 1: like some conductors are better than others, like coppers a 341 00:21:13,600 --> 00:21:17,400 Speaker 1: really good conductor, and it also depends upon the thickness 342 00:21:17,400 --> 00:21:21,200 Speaker 1: of that material. A thin copper wire has a greater 343 00:21:21,280 --> 00:21:26,200 Speaker 1: electrical resistance than a thick copper cable for example. Well, 344 00:21:26,320 --> 00:21:31,159 Speaker 1: resistance means that as you transmit electricity across this conductor, 345 00:21:31,720 --> 00:21:36,120 Speaker 1: you'll see the electrical energy diminish over distance. And we 346 00:21:36,200 --> 00:21:39,760 Speaker 1: know that energy can be neither created nor destroyed, right, 347 00:21:39,840 --> 00:21:43,520 Speaker 1: so we're not destroying that energy. However, that energy is 348 00:21:43,560 --> 00:21:46,399 Speaker 1: converting from one type to another. In this case, the 349 00:21:46,440 --> 00:21:50,080 Speaker 1: resistance causes the conductive material to heat up and we 350 00:21:50,200 --> 00:21:53,280 Speaker 1: lose some of that electrical energy in the form of 351 00:21:53,320 --> 00:21:58,360 Speaker 1: waste heat. So if you want to push electricity further 352 00:21:59,200 --> 00:22:02,080 Speaker 1: down a trans mission line, you really have to use 353 00:22:02,160 --> 00:22:05,720 Speaker 1: a lot of voltage. And remember voltage is the pressure 354 00:22:05,840 --> 00:22:09,520 Speaker 1: in this system. So with alternating current, we can actually 355 00:22:09,600 --> 00:22:14,160 Speaker 1: use devices called transformers, which, while they are not robots, 356 00:22:14,200 --> 00:22:17,480 Speaker 1: they are arguably more than meets the eye. If you 357 00:22:17,520 --> 00:22:20,280 Speaker 1: were to look at an electrical transformer, like open up 358 00:22:20,280 --> 00:22:22,040 Speaker 1: a cover, and by the way, never do that, but 359 00:22:22,080 --> 00:22:25,000 Speaker 1: if you did do that, you would see that consists 360 00:22:25,160 --> 00:22:29,160 Speaker 1: of two coils of conductive wire wrapped around a core, 361 00:22:29,440 --> 00:22:33,240 Speaker 1: usually a ferro magnetic iron core in a simple transformer, 362 00:22:33,320 --> 00:22:37,120 Speaker 1: not necessarily a solid core, but a core. So passing 363 00:22:37,119 --> 00:22:41,320 Speaker 1: electricity through one coil of this wire induces electricity to 364 00:22:41,359 --> 00:22:44,639 Speaker 1: flow through the other. We already talked about inductance, right, 365 00:22:45,320 --> 00:22:49,439 Speaker 1: and the number of turns in each coil determines a 366 00:22:49,760 --> 00:22:53,240 Speaker 1: change in voltage. So let's say we've got coil number one, 367 00:22:53,359 --> 00:22:55,880 Speaker 1: which will call the primary coil. This is the coil 368 00:22:55,880 --> 00:22:59,879 Speaker 1: where we're going to send electricity through the wire. Let 369 00:23:00,040 --> 00:23:04,440 Speaker 1: say that primary coil has five turns and coil number two, 370 00:23:04,480 --> 00:23:08,720 Speaker 1: which is our secondary coil, has ten turns. Well, then 371 00:23:08,760 --> 00:23:12,800 Speaker 1: the ratio of turns is one to two, one for primary, 372 00:23:12,800 --> 00:23:16,200 Speaker 1: two for secondary, and the voltage of the second coil 373 00:23:16,240 --> 00:23:19,439 Speaker 1: will be double that of the first coil. This is 374 00:23:19,640 --> 00:23:23,360 Speaker 1: a step up transformer. We're stepping up the voltage. We're 375 00:23:23,359 --> 00:23:26,280 Speaker 1: increasing it by a factor of two. Now, if the 376 00:23:26,320 --> 00:23:29,800 Speaker 1: primary coil has ten turns and the secondary coil has 377 00:23:30,080 --> 00:23:33,720 Speaker 1: five turns, that's a two to one ratio. That means 378 00:23:33,720 --> 00:23:36,320 Speaker 1: the voltage of the second coil will be half that 379 00:23:36,440 --> 00:23:39,800 Speaker 1: of our first coil. This is a step down transformers. 380 00:23:39,800 --> 00:23:45,000 Speaker 1: So using this we can then push voltage up on 381 00:23:45,160 --> 00:23:49,399 Speaker 1: terrestrial power lines that are using alternating current. Again, this 382 00:23:49,480 --> 00:23:53,480 Speaker 1: only works with alternating current, not direct current. Then you 383 00:23:53,520 --> 00:23:57,640 Speaker 1: can increase the voltage for long distance transmission. You can 384 00:23:57,760 --> 00:24:03,240 Speaker 1: overcome the problem of loss due to resistance. Essentially, you've 385 00:24:03,280 --> 00:24:05,760 Speaker 1: just you turned the pressure on so much that it's 386 00:24:05,840 --> 00:24:08,919 Speaker 1: it's powering through that. Now you have to have the 387 00:24:09,000 --> 00:24:11,199 Speaker 1: right kind of cables to make that happen. You have 388 00:24:11,240 --> 00:24:13,800 Speaker 1: to have the transformers along the way, and you have 389 00:24:13,880 --> 00:24:17,359 Speaker 1: to step down the voltage before you feed that current 390 00:24:17,480 --> 00:24:21,679 Speaker 1: into say a business or a house. But it's entirely 391 00:24:21,680 --> 00:24:28,600 Speaker 1: possible to send electricity long distances overground using transformers. Anyway, 392 00:24:28,760 --> 00:24:32,040 Speaker 1: it's one thing to have a transformer above the waves. 393 00:24:32,400 --> 00:24:35,040 Speaker 1: If you've ever been around when a transformer blows out, 394 00:24:35,119 --> 00:24:39,840 Speaker 1: you know that this is a spectacular and often terrifying event. 395 00:24:40,200 --> 00:24:42,880 Speaker 1: There's a very loud boom, and it's like a thunderclap 396 00:24:43,000 --> 00:24:45,760 Speaker 1: or a shotgun going off, and then there's a shower 397 00:24:45,760 --> 00:24:48,320 Speaker 1: of sparks, and then all the power goes out and 398 00:24:48,359 --> 00:24:53,280 Speaker 1: it happens like in that order instantaneously. It seems now 399 00:24:53,320 --> 00:24:57,840 Speaker 1: that is inconvenient here upon the surface world, but below 400 00:24:57,880 --> 00:25:00,720 Speaker 1: the waves that would be much worse. So we have 401 00:25:00,800 --> 00:25:04,560 Speaker 1: to keep that in mind when we're talking about subsea cables. 402 00:25:04,600 --> 00:25:07,040 Speaker 1: Some of the solutions that we have to us here 403 00:25:07,040 --> 00:25:10,520 Speaker 1: on the surface would not be available to us underwater. 404 00:25:11,080 --> 00:25:15,440 Speaker 1: Now Samuel Morse himself tested the viability of an underwater 405 00:25:15,560 --> 00:25:19,159 Speaker 1: telegraph cable. He used a wire coated in tar and 406 00:25:19,280 --> 00:25:23,119 Speaker 1: India rubber to insulate the wire from the water because 407 00:25:23,119 --> 00:25:27,119 Speaker 1: he didn't want to lose electricity through the water. Essentially, 408 00:25:27,520 --> 00:25:30,399 Speaker 1: he submerged the wire in the New York Harbor and 409 00:25:30,440 --> 00:25:33,119 Speaker 1: he sent a telegraph signal through it, and the experiment 410 00:25:33,119 --> 00:25:35,320 Speaker 1: was a success. This signal came out the other side. 411 00:25:35,359 --> 00:25:38,879 Speaker 1: It worked. So as early as eighteen forty two, engineers 412 00:25:38,920 --> 00:25:43,439 Speaker 1: understood that an undersea cable was possible. The question was 413 00:25:43,520 --> 00:25:47,840 Speaker 1: could be made practical. The first underwater cable using Gutta 414 00:25:47,920 --> 00:25:51,880 Speaker 1: Percha as an insulator, was laid between Deut's and Cologne 415 00:25:52,359 --> 00:25:55,960 Speaker 1: across the River Rhine in eighteen forty seven, and then 416 00:25:56,080 --> 00:25:59,880 Speaker 1: in eighteen forty nine and Electrician with the Southeastern Railway 417 00:26:00,119 --> 00:26:03,440 Speaker 1: succeeded in laying two miles of cable off the coast 418 00:26:03,480 --> 00:26:08,440 Speaker 1: of England around the Kent region. But the first commercial 419 00:26:08,640 --> 00:26:12,119 Speaker 1: subseed cable would follow the year after that. It was 420 00:26:12,160 --> 00:26:16,320 Speaker 1: eighteen fifty and two brothers, Jacob Brett and John Watkins 421 00:26:16,359 --> 00:26:21,040 Speaker 1: Brett created the English Channel Submarine Telegraph Company. Now the 422 00:26:21,080 --> 00:26:24,440 Speaker 1: brothers had proposed laying a cable under the sea through 423 00:26:24,480 --> 00:26:27,879 Speaker 1: the English Channel and connecting the port towns of Dover, 424 00:26:28,119 --> 00:26:31,960 Speaker 1: England and Calais, France. Both England and France agreed to 425 00:26:32,000 --> 00:26:35,040 Speaker 1: this proposal, so the brothers got the funding they needed 426 00:26:35,080 --> 00:26:36,960 Speaker 1: to to try and make it happen, and they had 427 00:26:36,960 --> 00:26:39,640 Speaker 1: a deadline that they had to meet. So the brothers 428 00:26:39,680 --> 00:26:42,800 Speaker 1: purchased cable from a company called the Gutta Purchase Company. 429 00:26:43,480 --> 00:26:46,240 Speaker 1: The cable had Gutta Purchase insulation on it, but it 430 00:26:46,280 --> 00:26:49,600 Speaker 1: had no armoring to protect it from other hazards. So 431 00:26:49,680 --> 00:26:54,159 Speaker 1: it's a copper cable with a rubber like insulating layer 432 00:26:54,240 --> 00:26:57,239 Speaker 1: on the outside and that's it. Uh. It was just 433 00:26:57,280 --> 00:27:00,159 Speaker 1: a single copper wire too, it was not We're not 434 00:27:00,280 --> 00:27:03,359 Speaker 1: multiple cables or wires in this. So in many ways 435 00:27:03,640 --> 00:27:05,840 Speaker 1: this would be an experiment and ultimately it would be 436 00:27:05,880 --> 00:27:10,200 Speaker 1: only partially successful. Uh. In that really it was a failure, 437 00:27:10,240 --> 00:27:12,800 Speaker 1: but it taught them a lot of lessons. So the 438 00:27:12,800 --> 00:27:16,159 Speaker 1: cable the brothers used was too light to sink on 439 00:27:16,200 --> 00:27:19,080 Speaker 1: its own. It would not sink down to the sea floor. 440 00:27:19,600 --> 00:27:23,040 Speaker 1: So every one hundred yards or so, workers on board 441 00:27:23,400 --> 00:27:27,960 Speaker 1: the ship that would unspool the coil of cable, had 442 00:27:28,000 --> 00:27:32,439 Speaker 1: to attach lead weights to the cable. The weights ranged 443 00:27:32,520 --> 00:27:35,960 Speaker 1: between ten to thirty pounds, and the company used a 444 00:27:36,000 --> 00:27:39,760 Speaker 1: steam paddle ship called the Goliath to carry the cable 445 00:27:40,080 --> 00:27:44,359 Speaker 1: across the channel. They attached one end of the cable 446 00:27:44,400 --> 00:27:47,480 Speaker 1: to the dover shore side of the connection that went 447 00:27:47,560 --> 00:27:50,440 Speaker 1: up to a telegraph station, and then they began the 448 00:27:50,480 --> 00:27:53,080 Speaker 1: journey to France, and the ship would have to stop 449 00:27:53,160 --> 00:27:55,760 Speaker 1: every one yards or so in order to sink another 450 00:27:55,840 --> 00:27:58,560 Speaker 1: weight down with the cable to keep it in place 451 00:27:58,600 --> 00:28:00,880 Speaker 1: on the ocean floor, and had to stop each time. 452 00:28:00,920 --> 00:28:03,719 Speaker 1: So it's not like, you know, they were just leading 453 00:28:03,720 --> 00:28:05,639 Speaker 1: this out and staying in motion the whole time. They 454 00:28:05,640 --> 00:28:08,840 Speaker 1: stopped every hundred yards. It took the whole day for 455 00:28:08,920 --> 00:28:11,720 Speaker 1: the ship to lay the cable across to reach France, 456 00:28:12,080 --> 00:28:14,679 Speaker 1: and there the team attached the cable on the French 457 00:28:14,800 --> 00:28:19,439 Speaker 1: side they attempted to establish an electrical connection. I'm not 458 00:28:19,680 --> 00:28:23,960 Speaker 1: entirely sure the outcome of that attempt, Like the accounts 459 00:28:24,000 --> 00:28:28,000 Speaker 1: I read don't seem to really indicate whether or not 460 00:28:28,200 --> 00:28:31,000 Speaker 1: they were successful in getting an electrical signal all the 461 00:28:31,000 --> 00:28:34,040 Speaker 1: way across. At any rate, if they did, it was 462 00:28:34,080 --> 00:28:36,400 Speaker 1: a week one and by the next morning, the connection 463 00:28:36,440 --> 00:28:39,640 Speaker 1: had been severed and the line was just totally dead. 464 00:28:40,200 --> 00:28:43,080 Speaker 1: Not long after that, stories began to circulate that some 465 00:28:43,200 --> 00:28:46,760 Speaker 1: French fisherman had accidentally dredged up the cable in some 466 00:28:46,840 --> 00:28:50,960 Speaker 1: netting and then subsequently severed the cable. However, that story 467 00:28:51,040 --> 00:28:55,440 Speaker 1: was never verified. It didn't stop people from spreading variations 468 00:28:55,440 --> 00:28:58,800 Speaker 1: of that story, including variations that made the fisherman look 469 00:28:59,360 --> 00:29:05,400 Speaker 1: increasingly dimwitted over time. But the stories that were published 470 00:29:05,440 --> 00:29:08,800 Speaker 1: immediately following the failure actually suggested that it was the 471 00:29:08,840 --> 00:29:12,480 Speaker 1: action of the waves off the rocky coast of France 472 00:29:12,760 --> 00:29:15,320 Speaker 1: that was making the cable rub against rocks and then 473 00:29:15,440 --> 00:29:18,280 Speaker 1: and then break that way. What was certain is that 474 00:29:18,400 --> 00:29:21,720 Speaker 1: the cable did break, whether it was a human caused 475 00:29:21,840 --> 00:29:25,120 Speaker 1: error or because of the action of the waves, and 476 00:29:25,480 --> 00:29:28,479 Speaker 1: that's probably because there was no armoring on the cable. 477 00:29:29,000 --> 00:29:32,600 Speaker 1: So there you go. The brothers sent a letter to 478 00:29:32,640 --> 00:29:36,160 Speaker 1: the Times in England explaining that while their first attempt failed, 479 00:29:36,560 --> 00:29:38,640 Speaker 1: they had learned a great deal in the process, and 480 00:29:38,640 --> 00:29:41,239 Speaker 1: they explained that the thing that they had attempted had 481 00:29:41,320 --> 00:29:44,280 Speaker 1: never been done before, and as such they were going 482 00:29:44,560 --> 00:29:47,600 Speaker 1: in ignorant of what would and wouldn't work. But through 483 00:29:47,640 --> 00:29:51,400 Speaker 1: this experience they had learned some valuable lessons and were 484 00:29:51,400 --> 00:29:54,719 Speaker 1: more convinced than ever that a cable connecting England to 485 00:29:54,840 --> 00:29:59,240 Speaker 1: the European continent would work. Whether they wrote that letter 486 00:29:59,320 --> 00:30:02,160 Speaker 1: in an effort to, you know, make sure they still 487 00:30:02,200 --> 00:30:05,320 Speaker 1: had funding for future attempts, or this was a genuine 488 00:30:05,320 --> 00:30:08,520 Speaker 1: expression of their enthusiasm, I don't know. Maybe it was 489 00:30:08,560 --> 00:30:11,600 Speaker 1: a mixture of both, or maybe it was something else entirely. 490 00:30:11,640 --> 00:30:14,920 Speaker 1: But the important thing is they were right. When we 491 00:30:15,000 --> 00:30:24,080 Speaker 1: come back, I'll explain and tell the rest of their story, 492 00:30:25,600 --> 00:30:28,840 Speaker 1: all right. So the Brett brothers still had some time 493 00:30:28,920 --> 00:30:32,200 Speaker 1: left before their agreements with France and England would expire, 494 00:30:32,520 --> 00:30:36,480 Speaker 1: specifically with the French government, and if that happened, they 495 00:30:36,480 --> 00:30:38,240 Speaker 1: were going to have to go through the whole process 496 00:30:38,280 --> 00:30:41,320 Speaker 1: of securing permission all over again. That was not a guarantee, 497 00:30:41,400 --> 00:30:45,640 Speaker 1: especially you know, after having failed their first try. So 498 00:30:45,800 --> 00:30:48,240 Speaker 1: they were determined to make another go at it before 499 00:30:48,760 --> 00:30:51,760 Speaker 1: time was up, and this time they would add more 500 00:30:51,800 --> 00:30:55,600 Speaker 1: protections for the cable. That cable would contain not one, 501 00:30:55,960 --> 00:31:00,440 Speaker 1: but four copper wires, each insulated by Gutta percha. In fact, 502 00:31:00,800 --> 00:31:03,960 Speaker 1: h wire had a double layer of Gutta purchase installation, 503 00:31:04,080 --> 00:31:08,000 Speaker 1: so that you had a wire that was the core, 504 00:31:08,400 --> 00:31:10,920 Speaker 1: and then you had a rubber case essentially on the 505 00:31:10,960 --> 00:31:14,000 Speaker 1: outside of that, and then a second rubber case on 506 00:31:14,040 --> 00:31:17,200 Speaker 1: the outside of that. The engineers then bound those four 507 00:31:17,240 --> 00:31:22,920 Speaker 1: wires together with yarn soaked in tar and tallow, so 508 00:31:23,080 --> 00:31:27,680 Speaker 1: together the yarn tar tallow mixture. There's some other stuff 509 00:31:27,680 --> 00:31:31,680 Speaker 1: in there as well, and the four wires encased in 510 00:31:31,720 --> 00:31:35,840 Speaker 1: Gutta percha served as the core of the cable itself, 511 00:31:36,360 --> 00:31:39,920 Speaker 1: and that soaked yarn provided some more stability and strength. 512 00:31:40,240 --> 00:31:44,160 Speaker 1: The bound cables now formed a kind of rope, and 513 00:31:44,200 --> 00:31:47,680 Speaker 1: the next step was to weave ten strands of galvanized 514 00:31:47,720 --> 00:31:53,120 Speaker 1: iron wires around the rope to provide armor protection. Galvanization 515 00:31:53,200 --> 00:31:55,920 Speaker 1: is a process through which you apply a protective coating 516 00:31:56,040 --> 00:31:59,840 Speaker 1: of zinc into onto something like iron or steel. Typically, 517 00:31:59,840 --> 00:32:03,200 Speaker 1: the way it works is you make whatever thing you're 518 00:32:03,240 --> 00:32:06,000 Speaker 1: making out of iron or steel, and then you immerse 519 00:32:06,120 --> 00:32:10,440 Speaker 1: that in molten zinc, which then adheres to the exterior 520 00:32:10,680 --> 00:32:15,400 Speaker 1: of the metal. That helps prevent rusting, which has an 521 00:32:15,400 --> 00:32:18,240 Speaker 1: important consideration if you've got a cable that's going to 522 00:32:18,240 --> 00:32:21,600 Speaker 1: be submerged in salt water. Throughout its lifespan. You know, 523 00:32:21,960 --> 00:32:25,480 Speaker 1: saltwater will cause stuff to rust pretty darn quickly. So 524 00:32:25,760 --> 00:32:29,760 Speaker 1: the iron wires were protected with this zinc coating and 525 00:32:29,800 --> 00:32:32,720 Speaker 1: the they were they measured about five six of an 526 00:32:32,720 --> 00:32:35,680 Speaker 1: inch in diameter, and like I said, there were ten 527 00:32:35,760 --> 00:32:39,120 Speaker 1: of them that would be woven together to create the 528 00:32:39,320 --> 00:32:42,520 Speaker 1: armored sheath for this cable. Now, according to a piece 529 00:32:42,600 --> 00:32:46,760 Speaker 1: in the Illustrated London News, the brothers employed an engineer 530 00:32:46,840 --> 00:32:50,480 Speaker 1: named George Fenwick, who invented and built a machine in 531 00:32:50,600 --> 00:32:55,080 Speaker 1: just ten days to weave these iron wires around the 532 00:32:55,160 --> 00:32:59,040 Speaker 1: cable of you know, copper wire and yarn. And it 533 00:32:59,160 --> 00:33:01,840 Speaker 1: had to be fast, and it had to be delicate. 534 00:33:01,880 --> 00:33:04,440 Speaker 1: It could not damage the copper itself. If the copper 535 00:33:04,520 --> 00:33:09,600 Speaker 1: broke inside the rope, then you could have a broken connection. 536 00:33:09,880 --> 00:33:12,560 Speaker 1: I would love to describe this machine to you, but 537 00:33:12,600 --> 00:33:16,080 Speaker 1: I've only seen a few descriptions without visual aids. I 538 00:33:16,120 --> 00:33:20,080 Speaker 1: think I would really do a poor job of explaining it. 539 00:33:20,440 --> 00:33:22,840 Speaker 1: But let's talk about what the machine had to do. 540 00:33:23,480 --> 00:33:26,600 Speaker 1: It had to draw this rope, this this cable of 541 00:33:26,720 --> 00:33:30,400 Speaker 1: yarn and copper wires through a machine and had to 542 00:33:30,440 --> 00:33:34,200 Speaker 1: weave around that rope the iron wires in a pattern 543 00:33:34,240 --> 00:33:36,920 Speaker 1: that was tight enough to provide armor protection for the 544 00:33:36,960 --> 00:33:39,760 Speaker 1: copper inside, and it had to do it without breaking 545 00:33:39,760 --> 00:33:43,120 Speaker 1: the copper. The machine was able to draw off eleven 546 00:33:43,160 --> 00:33:46,959 Speaker 1: inches of cable in a single revolution of its steam engine, 547 00:33:47,360 --> 00:33:50,560 Speaker 1: and it had a revolutions per minute speed of eighteen, 548 00:33:50,760 --> 00:33:54,800 Speaker 1: so it would revolve eighteen times and eleven inches of 549 00:33:54,840 --> 00:33:57,800 Speaker 1: cable would go through each revolution. That means that if 550 00:33:57,800 --> 00:34:00,200 Speaker 1: I'm doing my math correctly, it could weave the iron 551 00:34:00,360 --> 00:34:03,840 Speaker 1: armoring for sixteen and a half feet of cable every minute, 552 00:34:04,280 --> 00:34:07,560 Speaker 1: which is pretty impressive now, granted they're making miles and 553 00:34:07,600 --> 00:34:11,759 Speaker 1: miles of cable. In fact, overall the primary cable was 554 00:34:11,880 --> 00:34:15,680 Speaker 1: twenty four miles long, and it took about three weeks 555 00:34:15,719 --> 00:34:18,480 Speaker 1: to make the whole thing, And the plan was to 556 00:34:18,520 --> 00:34:20,799 Speaker 1: use those twenty four miles of cable to span the 557 00:34:20,960 --> 00:34:24,680 Speaker 1: twenty one miles of distance between Dover and Clay, the 558 00:34:24,719 --> 00:34:27,560 Speaker 1: thought being that the three extra miles would be plenty 559 00:34:27,600 --> 00:34:29,919 Speaker 1: to deal for the fact that you're sinking it under 560 00:34:29,920 --> 00:34:32,920 Speaker 1: the water. As it turns out, the cable wasn't quite 561 00:34:33,000 --> 00:34:36,000 Speaker 1: long enough to reach, so in the end they actually 562 00:34:36,000 --> 00:34:39,760 Speaker 1: had to splice an additional mile of cable onto the 563 00:34:39,800 --> 00:34:43,320 Speaker 1: French side of this in order to make a connection work. 564 00:34:43,680 --> 00:34:46,759 Speaker 1: But fortunately that would work out. Now, the twenty four 565 00:34:46,800 --> 00:34:50,520 Speaker 1: miles of cable, the primary cable weighed around a hundred 566 00:34:50,600 --> 00:34:53,719 Speaker 1: eighty tons and when it was coiled up, it made 567 00:34:53,719 --> 00:34:56,279 Speaker 1: a coil that measured fifteen feet in diameter on the 568 00:34:56,280 --> 00:34:58,840 Speaker 1: inside of the coil thirty feet in diameter on the 569 00:34:58,880 --> 00:35:02,920 Speaker 1: outside of the coil. Once constructed, cruise loaded the cable 570 00:35:02,960 --> 00:35:06,680 Speaker 1: onto a steamship called the Blazer. Now the ship was 571 00:35:06,960 --> 00:35:10,880 Speaker 1: pretty much gutted before the cruise loaded the cable onto it. 572 00:35:10,920 --> 00:35:14,719 Speaker 1: They pretty much stripped it of everything and essentially it 573 00:35:14,760 --> 00:35:18,040 Speaker 1: became a barge that would be pulled by tug boats, 574 00:35:18,080 --> 00:35:20,879 Speaker 1: a pair of them. Now this was in Wapping, an 575 00:35:20,920 --> 00:35:24,240 Speaker 1: area in London on the Thames River, so the tug 576 00:35:24,280 --> 00:35:28,560 Speaker 1: boats would tow the Blazer out the Thames, down to 577 00:35:28,640 --> 00:35:32,399 Speaker 1: the sea and around the coast of England to Dover. Now, 578 00:35:32,400 --> 00:35:35,279 Speaker 1: the laying of the cable would not go smoothly. For 579 00:35:35,360 --> 00:35:38,439 Speaker 1: one thing. While the iron weaving machine was a work 580 00:35:38,480 --> 00:35:41,360 Speaker 1: of genius, and while it was able to work pretty quickly, 581 00:35:41,480 --> 00:35:46,600 Speaker 1: it was not always flawless. Um there were some breaks 582 00:35:46,800 --> 00:35:49,560 Speaker 1: in the iron wires along the length of the cable, 583 00:35:49,600 --> 00:35:52,240 Speaker 1: so you had little bits where, you know, a strand 584 00:35:52,280 --> 00:35:55,560 Speaker 1: of iron would be broken a little bit and it 585 00:35:55,600 --> 00:35:58,320 Speaker 1: would start to stick out. This created surfaces upon which 586 00:35:58,600 --> 00:36:02,840 Speaker 1: something could snag you weren't careful. This would become important 587 00:36:02,840 --> 00:36:05,360 Speaker 1: as the crew laid the cable between Dover and Calais, 588 00:36:05,680 --> 00:36:08,319 Speaker 1: and the first problem popped up right away. So the 589 00:36:08,360 --> 00:36:12,360 Speaker 1: coil still aboard the blazer, which again was being towed 590 00:36:12,400 --> 00:36:17,000 Speaker 1: by some tug steamers, snagged as it was uncoiling and 591 00:36:17,280 --> 00:36:20,080 Speaker 1: they were laying the cable into the sea. So the 592 00:36:20,120 --> 00:36:22,960 Speaker 1: tug boats had started moving a little too quickly. They 593 00:36:22,960 --> 00:36:26,600 Speaker 1: got up to a top speed that was like five knots, 594 00:36:26,600 --> 00:36:29,400 Speaker 1: which isn't super fast, but it was too fast to 595 00:36:29,680 --> 00:36:34,720 Speaker 1: uncoil the cable safely. And one of those broken iron 596 00:36:35,280 --> 00:36:40,840 Speaker 1: wires snagged on a surface as the the cable was 597 00:36:40,880 --> 00:36:43,880 Speaker 1: being uncoiled and put into the ocean, and an eighteen 598 00:36:43,960 --> 00:36:48,319 Speaker 1: yard length of that cable was stripped of that one 599 00:36:48,400 --> 00:36:52,200 Speaker 1: strand of iron wire, not the whole iron casing, but 600 00:36:52,360 --> 00:36:55,560 Speaker 1: one of the ten strands of wires stripped away. Now 601 00:36:55,880 --> 00:36:59,080 Speaker 1: the armor consisted of ten iron wire, so this was 602 00:36:59,120 --> 00:37:03,799 Speaker 1: not you know, a true disaster, but it did send 603 00:37:03,800 --> 00:37:07,760 Speaker 1: the message that they needed to go a little more slowly, 604 00:37:08,200 --> 00:37:10,560 Speaker 1: which was tough because the weather was also really bad, 605 00:37:10,600 --> 00:37:13,319 Speaker 1: so spending more time out in bad weather on the 606 00:37:13,360 --> 00:37:16,239 Speaker 1: sea not a high priority. But the captains of the 607 00:37:16,239 --> 00:37:20,719 Speaker 1: tug boats were told don't hit the steam quite so hard. 608 00:37:21,520 --> 00:37:23,959 Speaker 1: Then the weather started getting rough and the tiny ship 609 00:37:24,040 --> 00:37:27,399 Speaker 1: was tossed, so to speak, And as the ships got 610 00:37:27,440 --> 00:37:30,400 Speaker 1: closer to France, the seas were very heavy and a 611 00:37:30,440 --> 00:37:33,279 Speaker 1: strong wind was blowing, and at one point the tow 612 00:37:33,400 --> 00:37:37,080 Speaker 1: rope connecting the Blazer to the tug ships snapped and 613 00:37:37,200 --> 00:37:40,360 Speaker 1: the Blazer was set adrift, and it took some time 614 00:37:40,560 --> 00:37:43,399 Speaker 1: to reconnect the Blazer to the tug ships, during which 615 00:37:43,440 --> 00:37:46,240 Speaker 1: the Blazer had drifted about a mile and a half 616 00:37:46,400 --> 00:37:50,520 Speaker 1: off course. The delay meant that it was near nightfall 617 00:37:50,800 --> 00:37:53,360 Speaker 1: when they were finally approaching France, and the storms in 618 00:37:53,360 --> 00:37:56,680 Speaker 1: the darkness meant conditions were just too dangerous to complete 619 00:37:56,680 --> 00:38:00,480 Speaker 1: the connection, so the Blazer anchored for the night. The 620 00:38:00,480 --> 00:38:03,239 Speaker 1: next day, the weather was not much better, and the 621 00:38:03,239 --> 00:38:05,759 Speaker 1: tug ships pulled the Blazer to within a mile of 622 00:38:05,840 --> 00:38:08,160 Speaker 1: the shore of France, but they couldn't really get any 623 00:38:08,200 --> 00:38:11,680 Speaker 1: closer because of the weather. So the crew decided to 624 00:38:11,880 --> 00:38:16,200 Speaker 1: attach the end of the cable to a buoy, and 625 00:38:16,360 --> 00:38:19,320 Speaker 1: this freed up the Blazer and the tug ships towed 626 00:38:19,320 --> 00:38:22,160 Speaker 1: it back to England. Now the captain of another ship 627 00:38:22,200 --> 00:38:25,759 Speaker 1: called the Fearless took over his ship, took up the 628 00:38:25,920 --> 00:38:28,239 Speaker 1: end of the cable that was secured to the buoy, 629 00:38:28,280 --> 00:38:31,200 Speaker 1: and then brought a little bit further, like another hundred 630 00:38:31,239 --> 00:38:35,000 Speaker 1: yards or so, and then moored the cable. And the 631 00:38:35,000 --> 00:38:40,040 Speaker 1: next day representatives from the Gutta Perch Company UH they 632 00:38:40,239 --> 00:38:42,319 Speaker 1: joined the Fearless and they brought along with them an 633 00:38:42,360 --> 00:38:47,800 Speaker 1: additional mile length of cable. So then the crew spliced 634 00:38:47,840 --> 00:38:50,960 Speaker 1: the two cables together and formed a new one. And 635 00:38:51,000 --> 00:38:53,920 Speaker 1: then they brought the fresh length of cable onto shore 636 00:38:53,960 --> 00:38:56,719 Speaker 1: of France after much delay, and a French crew then 637 00:38:57,200 --> 00:39:00,840 Speaker 1: laid the cable up to the French connection uh not 638 00:39:00,960 --> 00:39:04,160 Speaker 1: the movie, but the actual connecting terminal point for the 639 00:39:04,200 --> 00:39:07,160 Speaker 1: French side of the telegraph system, and the crew also 640 00:39:07,200 --> 00:39:10,439 Speaker 1: buried some of the cable to keep it protected. Upon 641 00:39:10,600 --> 00:39:12,759 Speaker 1: testing the cable, the teams were pleased to find out 642 00:39:12,760 --> 00:39:16,560 Speaker 1: that they had established a working signal line between Dover 643 00:39:16,680 --> 00:39:19,719 Speaker 1: and Calais and they actually did a heck of a 644 00:39:19,719 --> 00:39:22,160 Speaker 1: demonstration to prove that it was working. It's one of 645 00:39:22,160 --> 00:39:26,919 Speaker 1: my favorite stories about testing the technology. Okay, so here's 646 00:39:26,960 --> 00:39:30,480 Speaker 1: what they did. At Calais. There are fortifications, it's a 647 00:39:30,600 --> 00:39:34,160 Speaker 1: port town on France, and that's across the English Channel 648 00:39:34,280 --> 00:39:38,640 Speaker 1: from England. England and France had had sometimes a contentious 649 00:39:38,680 --> 00:39:44,000 Speaker 1: relationship in history. So there were ramparts along parts of 650 00:39:44,080 --> 00:39:49,480 Speaker 1: Calais and on them was a cannon. So engineers connected 651 00:39:49,520 --> 00:39:54,120 Speaker 1: the cannon to this electrical signal line connected back to England, 652 00:39:54,880 --> 00:39:59,640 Speaker 1: and a current with sufficient voltage would ignite the cannon 653 00:39:59,719 --> 00:40:02,240 Speaker 1: sign system, which would then cause the cannon to fire 654 00:40:02,360 --> 00:40:06,520 Speaker 1: and so many miles away across the English Channel, an 655 00:40:06,520 --> 00:40:10,799 Speaker 1: engineer sent a pulse of electricity from Dover, England to 656 00:40:10,920 --> 00:40:14,360 Speaker 1: go through the subsequent cable, and that provided the juice 657 00:40:14,400 --> 00:40:19,120 Speaker 1: necessary to make a cannon in France fire. Obviously, this 658 00:40:19,200 --> 00:40:21,759 Speaker 1: was not the first time that the English made the 659 00:40:21,760 --> 00:40:24,560 Speaker 1: French fire a cannon, but at least this time there 660 00:40:24,560 --> 00:40:28,640 Speaker 1: were no hostilities involved. Now, the telegraph in this case 661 00:40:28,960 --> 00:40:32,480 Speaker 1: used the pointing needle mechanism that I referred to earlier, 662 00:40:32,560 --> 00:40:36,680 Speaker 1: rather than Samuel Morris's version that makes sense. Morse code 663 00:40:37,000 --> 00:40:41,160 Speaker 1: when it was first introduced, only had codes for the 664 00:40:41,239 --> 00:40:45,239 Speaker 1: letters that we typically encounter here in America. So in 665 00:40:45,280 --> 00:40:49,880 Speaker 1: America it's pretty unusual to run into characters that have 666 00:40:50,040 --> 00:40:53,240 Speaker 1: an accent on them, like an accent ague, for example, 667 00:40:53,800 --> 00:40:56,719 Speaker 1: or letters that have an oomb out or anything like that. 668 00:40:57,320 --> 00:41:00,920 Speaker 1: Over in Europe it's more commons, so they needed to 669 00:41:00,960 --> 00:41:05,080 Speaker 1: have a method that would allow for that. Now, despite 670 00:41:05,080 --> 00:41:08,520 Speaker 1: all the bumps along the way, the cable seemed to 671 00:41:08,560 --> 00:41:12,240 Speaker 1: work exactly as was intended. The insulation around the copper 672 00:41:12,280 --> 00:41:15,319 Speaker 1: wires remained secure even after some of that iron armor 673 00:41:15,360 --> 00:41:18,560 Speaker 1: had been stripped off. The cable and the Submarine Telegraph 674 00:41:18,640 --> 00:41:23,400 Speaker 1: Company that the name had simplified over the years received 675 00:41:23,400 --> 00:41:26,760 Speaker 1: some criticism for putting the entire endeavor at risk because 676 00:41:26,800 --> 00:41:30,600 Speaker 1: they did this operation during unfavorable weather. Essentially, some people 677 00:41:30,640 --> 00:41:33,640 Speaker 1: were saying, you're really lucky that this works, because you're 678 00:41:33,680 --> 00:41:37,560 Speaker 1: an idiot for having to lay down subseed cable when 679 00:41:38,080 --> 00:41:42,600 Speaker 1: the cs are so rough. However, in defense of the company, 680 00:41:42,640 --> 00:41:44,880 Speaker 1: they didn't really have a choice in the matter because 681 00:41:44,920 --> 00:41:48,640 Speaker 1: they were rapidly approaching the deadline that France had set, 682 00:41:48,719 --> 00:41:51,320 Speaker 1: and if they did not get the cable laid in time, 683 00:41:52,239 --> 00:41:55,000 Speaker 1: then the whole project was going to be a failure 684 00:41:55,200 --> 00:41:58,040 Speaker 1: and all the money was going to go away. So 685 00:41:58,600 --> 00:42:01,120 Speaker 1: really this all happened in the nick of time, and 686 00:42:01,160 --> 00:42:04,640 Speaker 1: those risks were necessary once if they wanted to actually, 687 00:42:04,840 --> 00:42:08,600 Speaker 1: you know, make this work now. To send signals through 688 00:42:08,600 --> 00:42:11,680 Speaker 1: cables of great length, companies need to supply, like I said, 689 00:42:11,719 --> 00:42:15,239 Speaker 1: a good deal of voltage to overcome resistance. But there 690 00:42:15,239 --> 00:42:19,719 Speaker 1: were other issues that placed fundamental limits on how far 691 00:42:19,960 --> 00:42:24,279 Speaker 1: or how fast you could transmit electricity and thus information 692 00:42:24,840 --> 00:42:30,120 Speaker 1: across simple copper wire. So we're going to talk a 693 00:42:30,120 --> 00:42:32,759 Speaker 1: little bit about that before I wrap up, and then 694 00:42:33,520 --> 00:42:37,359 Speaker 1: in the next episode we'll talk more about the Transatlantic 695 00:42:37,719 --> 00:42:42,200 Speaker 1: telegraph cables. So I've mentioned resistance and voltage and current, 696 00:42:42,640 --> 00:42:46,399 Speaker 1: but things get significantly more complicated when we start talking 697 00:42:46,400 --> 00:42:49,600 Speaker 1: about transmitting a signal across very long cables that are 698 00:42:49,719 --> 00:42:53,960 Speaker 1: underwater or underground. Now, technically these things happen in shorter 699 00:42:54,080 --> 00:42:57,960 Speaker 1: cables too, but if the distance is short enough, you 700 00:42:58,040 --> 00:43:01,000 Speaker 1: might not even notice that there's a problem, or it 701 00:43:01,040 --> 00:43:04,600 Speaker 1: may not be bad enough for it to be an issue. 702 00:43:04,960 --> 00:43:07,800 Speaker 1: But we definitely see them over great distances with cables 703 00:43:07,840 --> 00:43:11,600 Speaker 1: that are submerged or buried Michael Faraday, whom I've talked 704 00:43:11,640 --> 00:43:15,200 Speaker 1: about frequently on this podcast a true Genius U He 705 00:43:15,239 --> 00:43:20,200 Speaker 1: had a hypothesis about undersea cables or buried cables, and 706 00:43:20,640 --> 00:43:23,600 Speaker 1: this was based off the observation that another smarty pants 707 00:43:23,640 --> 00:43:27,399 Speaker 1: named Sir Francis Ronalds had observed way back in three 708 00:43:27,880 --> 00:43:30,279 Speaker 1: He saw that if you had two insulated wires of 709 00:43:30,320 --> 00:43:34,400 Speaker 1: equal length and gauge, and you buried one of them, 710 00:43:34,440 --> 00:43:37,560 Speaker 1: and you tried to pass electrical signals through each of them, 711 00:43:37,600 --> 00:43:40,680 Speaker 1: the above ground one would work just as you would expect, 712 00:43:40,760 --> 00:43:43,160 Speaker 1: but the one that was buried would have trouble carrying 713 00:43:43,200 --> 00:43:45,840 Speaker 1: the signal. The signals seemed to be moving more slowly, 714 00:43:45,880 --> 00:43:49,520 Speaker 1: as if something were putting the brakes along the way. 715 00:43:49,840 --> 00:43:52,920 Speaker 1: Faraday concluded that this was because of induction between the 716 00:43:52,960 --> 00:43:55,880 Speaker 1: wire and the earth surrounding the wire, or, in the 717 00:43:55,920 --> 00:44:00,520 Speaker 1: case of submerged sea cables, the water. So what does 718 00:44:00,520 --> 00:44:03,400 Speaker 1: that actually mean. Well, essentially, the cable and the water 719 00:44:03,800 --> 00:44:07,120 Speaker 1: behave kind of like a laden jar or liden jar. 720 00:44:07,520 --> 00:44:11,600 Speaker 1: If you pass an electric current through the cable, it 721 00:44:11,640 --> 00:44:16,120 Speaker 1: induces an electric charge and opposite electric charge in the water, 722 00:44:16,520 --> 00:44:20,879 Speaker 1: and opposite charges attract one another. This attraction is kind 723 00:44:20,880 --> 00:44:23,360 Speaker 1: of like putting the brakes down on a signal. It 724 00:44:23,400 --> 00:44:25,719 Speaker 1: doesn't stop it, but it slows it down. They called 725 00:44:25,760 --> 00:44:30,080 Speaker 1: it retardation of a signal. Faraday described the flow of 726 00:44:30,120 --> 00:44:33,840 Speaker 1: electricity along and underwater cable as behaving like a wave, 727 00:44:33,920 --> 00:44:39,200 Speaker 1: which honestly was really ingenious. He said that the result 728 00:44:39,360 --> 00:44:43,080 Speaker 1: is you would first get a weak signal from the 729 00:44:43,160 --> 00:44:46,560 Speaker 1: receiving end, and that signal would slowly grow in strength. 730 00:44:47,120 --> 00:44:49,600 Speaker 1: Then the strength would start to fade away again, and 731 00:44:49,600 --> 00:44:52,840 Speaker 1: this would happen in cycles again, very much like waves 732 00:44:52,880 --> 00:44:57,160 Speaker 1: crashing on the beach. Then we've got William Thompson, who 733 00:44:57,160 --> 00:45:00,480 Speaker 1: would later be known as Lord Kelvin, and they're super 734 00:45:00,520 --> 00:45:03,719 Speaker 1: important scientist. Not only would he propose the system of 735 00:45:03,760 --> 00:45:07,040 Speaker 1: absolute temperature, and we would later describe this in units 736 00:45:07,160 --> 00:45:11,719 Speaker 1: called kelvin zero, kelvin being absolute zero, he was also 737 00:45:11,800 --> 00:45:17,160 Speaker 1: instrumental in telegraphic engineering. Thompson built on Faraday's work, realizing 738 00:45:17,200 --> 00:45:20,359 Speaker 1: that the diameter of the conductor was fundamentally important when 739 00:45:20,400 --> 00:45:22,480 Speaker 1: determining the speed at which a signal will travel through 740 00:45:22,480 --> 00:45:25,000 Speaker 1: a cable, and he also came up with an equation 741 00:45:25,120 --> 00:45:27,600 Speaker 1: to describe how signals passed through cable, and it goes 742 00:45:27,600 --> 00:45:30,239 Speaker 1: like this. The speed of a signal passing through a 743 00:45:30,280 --> 00:45:35,000 Speaker 1: wire decreases as the square of the cable length increases, 744 00:45:35,360 --> 00:45:40,600 Speaker 1: So signaling speed has an adversely proportional relationship to cable length, 745 00:45:40,920 --> 00:45:45,120 Speaker 1: assuming that you're sticking with the same cable gauge. Gauge 746 00:45:45,120 --> 00:45:48,319 Speaker 1: in this case relates to a cable's capacity and resistance. 747 00:45:48,600 --> 00:45:51,000 Speaker 1: The larger the diameter of the cable, the lower the 748 00:45:51,040 --> 00:45:56,319 Speaker 1: resistance will be. And we're going to stop here, but 749 00:45:56,440 --> 00:46:00,959 Speaker 1: that issue that Lord Kelvin found would become um one 750 00:46:00,960 --> 00:46:05,560 Speaker 1: of the big challenges to overcome when looking at laying 751 00:46:05,800 --> 00:46:08,759 Speaker 1: very long subseed cable. So in our next episode we'll 752 00:46:08,760 --> 00:46:13,800 Speaker 1: talk more about the quest to lay a cable along 753 00:46:13,840 --> 00:46:16,800 Speaker 1: the Atlantic Ocean so that we could connect Europe to 754 00:46:16,880 --> 00:46:20,720 Speaker 1: North America, and about the engineering issues that we needed 755 00:46:20,760 --> 00:46:24,239 Speaker 1: to figure out, and then about how Lord Kelvin came 756 00:46:24,320 --> 00:46:28,439 Speaker 1: up with even more important ideas about how to deal 757 00:46:28,480 --> 00:46:31,160 Speaker 1: with this so that it could become practical. But we'll 758 00:46:31,160 --> 00:46:33,920 Speaker 1: cover all that in our next episode. If you have 759 00:46:34,040 --> 00:46:37,799 Speaker 1: suggestions for future episodes, be like and tricks send me 760 00:46:38,160 --> 00:46:40,520 Speaker 1: a message on Twitter. The handle we use is text 761 00:46:40,520 --> 00:46:45,759 Speaker 1: stuff hsw and I'll talk to you again really soon. 762 00:46:50,960 --> 00:46:53,960 Speaker 1: Text Stuff is an I heart Radio production. For more 763 00:46:54,040 --> 00:46:57,440 Speaker 1: podcasts from my heart Radio, visit the i heart Radio app, 764 00:46:57,600 --> 00:47:00,760 Speaker 1: Apple Podcasts, or wherever you listen to your favorite chips