1 00:00:03,483 --> 00:00:06,334 In 1832, mathematician, Carl Gauss, 2 00:00:06,334 --> 00:00:08,700 and physics professor, Wilhelm Weber, 3 00:00:08,700 --> 00:00:10,942 designed a system which allowed them to communicate 4 00:00:10,942 --> 00:00:14,005 at a distance while they worked on their experiments – 5 00:00:14,005 --> 00:00:18,241 connecting the observatory with the physical laboratory. 6 00:00:18,241 --> 00:00:20,606 They solved a really important problem, 7 00:00:20,606 --> 00:00:22,868 which was more of a puzzle: 8 00:00:22,868 --> 00:00:25,047 how to send all letters of the alphabet 9 00:00:25,047 --> 00:00:28,100 using one circuit – or a line. 10 00:00:28,100 --> 00:00:30,560 And their system used a galvanometer, 11 00:00:30,560 --> 00:00:33,407 since it was known that electric current, passing through 12 00:00:33,407 --> 00:00:35,719 a coil, creates a magnetic field pointing through 13 00:00:35,719 --> 00:00:39,086 the center of the loop, which could deflect a needle. 14 00:00:39,086 --> 00:00:42,047 But instead of merely moving a needle at a distance, 15 00:00:42,047 --> 00:00:44,922 their system used a switch which could reverse 16 00:00:44,922 --> 00:00:48,798 the direction of current instantly. 17 00:00:48,798 --> 00:00:50,409 This would cause the magnetic field 18 00:00:50,409 --> 00:00:52,349 around the coil to reverse, 19 00:00:52,349 --> 00:00:55,918 and the needle would deflect either to the right or left, 20 00:00:55,918 --> 00:00:58,268 depending on the direction of current – 21 00:00:58,268 --> 00:01:02,035 thus, giving them two different signaling events – 22 00:01:02,035 --> 00:01:05,927 or 'symbols' – right or left deflection. 23 00:01:05,927 --> 00:01:08,666 Most importantly, he assigned shorter 24 00:01:08,666 --> 00:01:11,913 symbols for the most common letters. 25 00:01:11,913 --> 00:01:14,658 [For instance,] 'A' was a single right deflection. 26 00:01:14,658 --> 00:01:17,384 And 'E' was a single left deflection. 27 00:01:17,384 --> 00:01:20,406 And he used the longer codes for less common letters, 28 00:01:20,406 --> 00:01:25,501 such as 'K,' which was three right deflections. 29 00:01:25,501 --> 00:01:28,658 And at the time, the speed of transmission 30 00:01:28,658 --> 00:01:33,119 was around nine letters per minute. 31 00:01:33,119 --> 00:01:35,656 All the needle telegraphs which followed 32 00:01:35,656 --> 00:01:38,079 suffered from a similar limitation – 33 00:01:38,079 --> 00:01:41,287 and it was an engineering problem. 34 00:01:41,287 --> 00:01:44,209 The 'signaling rate' was slow. 35 00:01:44,209 --> 00:01:45,900 Now the the signaling rate was the 36 00:01:45,900 --> 00:01:48,182 number of deflections per minute 37 00:01:48,182 --> 00:01:51,429 which could be accurately transmitted and received. 38 00:01:51,429 --> 00:01:53,590 And if you squished signaling events together, 39 00:01:53,590 --> 00:01:56,101 the receiver would get confused, due to jitter – 40 00:01:56,101 --> 00:01:57,779 resulting in errors – 41 00:01:57,779 --> 00:02:01,395 similar to how sustained notes on a piano will bleed 42 00:02:01,395 --> 00:02:06,425 together and become less recognizable – if you play rapidly. 43 00:02:06,425 --> 00:02:08,454 And over time, the signaling rate 44 00:02:08,454 --> 00:02:11,023 was incrementally improved. 45 00:02:11,023 --> 00:02:12,368 One improvement was to add 46 00:02:12,368 --> 00:02:15,916 a small permanent magnet to the outside of the coil. 47 00:02:15,916 --> 00:02:17,689 This helped pull the needle back to 48 00:02:17,689 --> 00:02:20,621 neutral position, after each deflection. 49 00:02:20,621 --> 00:02:22,778 And these designs led to a wide range of 50 00:02:22,778 --> 00:02:26,613 needle telegraphs, which were deployed across Europe. 51 00:02:26,613 --> 00:02:29,026 The Electric Telegraph Company 52 00:02:29,026 --> 00:02:32,201 was the first public telegraph company. 53 00:02:32,201 --> 00:02:35,608 It was formed, in 1846, after its owners purchased 54 00:02:35,608 --> 00:02:39,339 the key needle-telegraph patents at the time. 55 00:02:42,150 --> 00:02:45,633 But the speed of these various needle telegraphs 56 00:02:45,633 --> 00:02:50,316 never surpassed around 60 letters per minute – 57 00:02:54,252 --> 00:02:57,097 as each needle couldn't signal much faster than 58 00:02:57,097 --> 00:02:59,829 one deflection per second. 59 00:02:59,829 --> 00:03:02,392 And initially, the company billed customers 60 00:03:02,392 --> 00:03:04,587 based on single messages – 61 00:03:04,587 --> 00:03:07,269 which could hold up to twenty words – 62 00:03:07,269 --> 00:03:09,822 which is about the length of a 'tweet.' 63 00:03:09,822 --> 00:03:13,579 And by 1848, the cost of sending a single message 64 00:03:13,579 --> 00:03:17,728 from London to Edinburgh was sixteen shillings. 65 00:03:17,728 --> 00:03:19,859 And this was around one week's salary for, say, 66 00:03:19,859 --> 00:03:23,422 a shop owner at the time. 67 00:03:23,422 --> 00:03:25,427 So this technology was initially 68 00:03:25,427 --> 00:03:29,747 out of the [reach] of common people. 69 00:03:29,747 --> 00:03:32,988 In the United States, the commercialization of the telegraph 70 00:03:32,988 --> 00:03:36,834 was led by a portrait painter, named Samuel Morse, 71 00:03:36,834 --> 00:03:38,092 who had followed development 72 00:03:38,092 --> 00:03:41,130 of the needle telegraphs in Europe. 73 00:03:41,130 --> 00:03:43,690 Morse is important. because he focused on 74 00:03:43,690 --> 00:03:47,520 speeding up the rate at which letters could travel. 75 00:03:47,520 --> 00:03:49,659 He did away with needles. 76 00:03:49,659 --> 00:03:53,158 And in [1838], he initially submitted a patent 77 00:03:53,158 --> 00:03:55,640 based on the idea that electric current 78 00:03:55,640 --> 00:03:58,340 could either flow or be interrupted – 79 00:03:58,340 --> 00:04:03,185 and interruptions could be organized to create meaning. 80 00:04:03,185 --> 00:04:06,335 Though his designs on how to produce these interruptions 81 00:04:06,335 --> 00:04:09,399 were complicated – involving a convoluted system of 82 00:04:09,399 --> 00:04:12,264 gears, levers and electromagnets. 83 00:04:12,264 --> 00:04:14,938 However, his system was greatly simplified 84 00:04:14,938 --> 00:04:18,643 after his collaborations with Alfred Vail. 85 00:04:18,643 --> 00:04:21,756 This led to an iconic piece of user interface – 86 00:04:21,756 --> 00:04:25,721 the simple spring-loaded lever – or 'key' – 87 00:04:25,721 --> 00:04:29,218 which could be controlled with the tap of a finger. 88 00:04:29,218 --> 00:04:32,532 And on the receiving end was a spring-loaded lever 89 00:04:32,532 --> 00:04:34,560 that could be pulled and released 90 00:04:34,560 --> 00:04:37,389 by a strong electromagnet. 91 00:04:44,912 --> 00:04:49,106 To create a difference akin to the left-right deflection, 92 00:04:49,106 --> 00:04:55,050 he varied the length of a key press, or the pulse width. 93 00:04:55,050 --> 00:04:58,368 The closure of a switch for a very short time 94 00:04:58,368 --> 00:05:00,499 was called a 'dot.' 95 00:05:00,499 --> 00:05:02,489 And the dot can be thought of as 96 00:05:02,489 --> 00:05:07,390 the basic unit of time in Morse code. 97 00:05:07,390 --> 00:05:09,192 And the closure of the switch 98 00:05:09,192 --> 00:05:12,672 for three units of time represented a 'dash.' 99 00:05:12,672 --> 00:05:18,145 [SOUND OF LETTERS BEING SENT BY MORSE CODE.] 100 00:05:18,145 --> 00:05:20,800 Spacing exactly right. 101 00:05:20,800 --> 00:05:23,054 Very small, tight spaces between 102 00:05:23,054 --> 00:05:25,861 the dits and dahs in a character. 103 00:05:25,861 --> 00:05:27,071 Didah dit. 104 00:05:28,423 --> 00:05:30,079 [LETTER BEING SENT BY MORSE CODE.] 105 00:05:30,079 --> 00:05:31,042 Didah dit dit. 106 00:05:31,042 --> 00:05:32,520 [LETTER BEING SENT BY MORSE CODE.] 107 00:05:33,074 --> 00:05:35,028 And this was the source of difference 108 00:05:35,028 --> 00:05:37,534 in their coding strategy. 109 00:05:37,534 --> 00:05:41,873 Starting with an initial dot or dash – left or right branch – 110 00:05:41,873 --> 00:05:46,170 which then leads to another dot or dash, and so on. 111 00:05:46,170 --> 00:05:48,796 And the scheme assigned shorter symbol sequences 112 00:05:48,796 --> 00:05:50,599 to more probable letters – 113 00:05:50,599 --> 00:05:52,299 based on the letter frequencies – 114 00:05:52,299 --> 00:05:55,265 which could be tabulated from books. 115 00:05:55,265 --> 00:05:57,065 So nodes high up in the tree – 116 00:05:57,065 --> 00:06:00,335 such as a single dot – represented 'E.' 117 00:06:00,335 --> 00:06:03,125 A single dash represented 'T.' 118 00:06:03,125 --> 00:06:05,469 And as we move down the tree, 119 00:06:05,469 --> 00:06:08,037 we place less common letters. 120 00:06:08,037 --> 00:06:13,727 And after a letter, this system inserts a three-unit pause. 121 00:06:13,727 --> 00:06:16,683 Spacing between the characters in a word or group 122 00:06:16,683 --> 00:06:19,411 is uniform too – but longer. 123 00:06:19,411 --> 00:06:23,065 [LETTERS BEING SENT BY MORSE CODE.] 124 00:06:23,065 --> 00:06:27,360 It's important to realize that the meaning of these messages 125 00:06:27,360 --> 00:06:30,280 was intertwined with the timing [used when sending] them. 126 00:06:30,280 --> 00:06:31,941 Are you wondering if proper spacing 127 00:06:31,941 --> 00:06:34,061 is really so important? 128 00:06:34,061 --> 00:06:36,557 Or is it no more than an extra refinement – 129 00:06:36,557 --> 00:06:39,440 a nice thing to do – like neat handwriting? 130 00:06:39,440 --> 00:06:42,184 If you think so, you're wrong. And I'll show you why. 131 00:06:42,184 --> 00:06:47,525 [LETTERS BEING SENT BY MORSE CODE] 132 00:06:47,525 --> 00:06:50,972 Dit for dit, and dah for dah, they match. 133 00:06:51,532 --> 00:06:53,408 Only the spacing makes the difference 134 00:06:53,408 --> 00:06:58,317 between one word and the other. 135 00:06:58,317 --> 00:06:59,911 So to send the word 'Paris,' 136 00:06:59,911 --> 00:07:01,747 we would first need to think of it as 137 00:07:01,747 --> 00:07:06,833 'P [space] A [space] R [space] I [space] S.' 138 00:07:06,833 --> 00:07:10,396 The signaling rate of this system was directly related 139 00:07:10,396 --> 00:07:12,585 to the tempo of the signal. 140 00:07:12,585 --> 00:07:16,372 And music analogies were used inside training videos. 141 00:07:16,372 --> 00:07:21,110 What he was sending was standard test word: 'PARIS.' 142 00:07:21,110 --> 00:07:22,837 And there you are. 143 00:07:22,837 --> 00:07:26,212 Each peak is a dit – or a dah. 144 00:07:26,212 --> 00:07:29,421 Each valley, a space. 145 00:07:29,421 --> 00:07:33,606 This is excellent sending. Uniform and rhythmic. 146 00:07:35,513 --> 00:07:38,666 This is an example of poor hand sending. 147 00:07:38,666 --> 00:07:43,438 Same word: 'PARIS.' But look at the difference. 148 00:07:43,438 --> 00:07:48,131 Irregular dits and dahs. Haphazard spacing. 149 00:07:48,131 --> 00:07:51,726 No uniformity. No rhythm. 150 00:07:51,726 --> 00:07:55,221 Amazingly, it was the simplicity of this keying system 151 00:07:55,221 --> 00:07:57,169 which made it much faster 152 00:07:57,169 --> 00:07:59,205 than any of the buttons and cranks 153 00:07:59,205 --> 00:08:02,536 employed by the needle telegraphs in Europe. 154 00:08:02,536 --> 00:08:07,546 The letter rate jumped to 135 letters per minute – 155 00:08:07,546 --> 00:08:10,518 or more, with trained operators. 156 00:08:10,518 --> 00:08:15,262 And on May 24th, 1844, the first successful transmission 157 00:08:15,262 --> 00:08:19,727 was the message, "What hath God wrought?" 158 00:08:19,727 --> 00:08:22,925 And the next day, it was reported by the New York Tribune 159 00:08:22,925 --> 00:08:26,109 that, "The miracle of annihilation of space 160 00:08:26,109 --> 00:08:27,892 is at length performed." 161 00:08:27,892 --> 00:08:31,333 Consider that, at the time, 90% of messages 162 00:08:31,333 --> 00:08:34,469 were still transported by horseback. 163 00:08:34,469 --> 00:08:37,622 Immediately, this technology was becoming critical 164 00:08:37,622 --> 00:08:40,413 to the success of [the] military, newspapers, 165 00:08:40,413 --> 00:08:42,654 financial traders, crime-fighting [organizations, etc.]. 166 00:08:42,654 --> 00:08:46,022 Any business that relied on information 167 00:08:46,022 --> 00:08:49,291 now relied on the telegraph – and Morse code. 168 00:08:49,291 --> 00:08:51,785 By 1900, the prices had dropped 169 00:08:51,785 --> 00:08:54,643 to 30 cents per message – as traffic surged 170 00:08:54,643 --> 00:09:00,509 to over 63.2 million messages sent that year. 171 00:09:00,509 --> 00:09:03,907 As people begin using this system, they naturally 172 00:09:03,907 --> 00:09:06,234 thought of ways to save money. 173 00:09:06,234 --> 00:09:09,251 This led to popular code books that 174 00:09:09,251 --> 00:09:12,707 mapped words to common sentences. 175 00:09:12,707 --> 00:09:16,511 For example, 'Blade' would actually mean 176 00:09:16,511 --> 00:09:18,882 'Please name and reserve, for myself and family, 177 00:09:18,882 --> 00:09:20,964 the following accommodations.' 178 00:09:20,964 --> 00:09:23,081 The telegraph companies frowned upon this, 179 00:09:23,081 --> 00:09:26,250 as they were happily charging people to be verbose. 180 00:09:26,250 --> 00:09:28,981 More letters equals more profit. 181 00:09:28,981 --> 00:09:34,250 It was now clear that information was an elastic term. 182 00:09:34,250 --> 00:09:36,840 A specific meaning was needed. 183 00:09:36,840 --> 00:09:39,718 An obvious question remained unanswered. 184 00:09:39,718 --> 00:09:41,952 If you are [charging to transmit] information – 185 00:09:41,952 --> 00:09:43,813 no matter the system – 186 00:09:43,813 --> 00:09:47,597 how should you [charge] to be fair to everyone? 187 00:09:47,597 --> 00:09:51,054 Number of letters – as a measure of information – 188 00:09:51,054 --> 00:09:53,471 would no longer suffice.