1 00:00:07,508 --> 00:00:09,842 Narrator: The war that defines a nation... 2 00:00:09,944 --> 00:00:12,878 Hinges on a campaign waged at sea... 3 00:00:13,381 --> 00:00:14,646 Captain: Fire! 4 00:00:14,749 --> 00:00:19,435 Narrator: That transforms naval warfare forever. 5 00:00:20,337 --> 00:00:23,305 James: The american civil war was not only the bloodiest conflict, 6 00:00:23,407 --> 00:00:26,675 It was in many ways the first modern conflict. 7 00:00:27,478 --> 00:00:28,744 Narrator: Secret weapons... 8 00:00:28,846 --> 00:00:32,381 Shocking surprises and stories of raw courage, 9 00:00:32,483 --> 00:00:35,134 All lost beneath the waves. 10 00:00:35,536 --> 00:00:36,969 Crew: I think we might have a shipwreck... 11 00:00:37,071 --> 00:00:39,038 James: We're on it. 12 00:00:43,544 --> 00:00:47,112 Narrator: Imagine if we could empty the oceans... 13 00:00:48,182 --> 00:00:50,866 Letting the water drain away 14 00:00:50,968 --> 00:00:54,002 To reveal the secrets of the sea floor. 15 00:00:54,805 --> 00:00:57,639 Now we can. 16 00:00:57,742 --> 00:00:59,808 Using accurate data... 17 00:00:59,910 --> 00:01:05,547 And astonishing technology to bring light once again 18 00:01:05,649 --> 00:01:08,267 To a lost world. 19 00:01:09,904 --> 00:01:13,872 How does this metal monster create a naval revolution? 20 00:01:14,475 --> 00:01:16,475 Anna: It had to have been terrifying. 21 00:01:16,577 --> 00:01:18,977 Imagine the horror. 22 00:01:19,613 --> 00:01:21,613 Narrator: What does a mangled wreck reveal 23 00:01:21,715 --> 00:01:24,399 About a top-secret arms race? 24 00:01:24,502 --> 00:01:27,770 Michael: There are secrets still left to be discovered. 25 00:01:27,872 --> 00:01:30,188 This was a legend. 26 00:01:31,041 --> 00:01:34,409 Narrator: And at terrifying new weapon destroys one of the 27 00:01:34,512 --> 00:01:37,112 Most powerful warships ever built. 28 00:01:37,214 --> 00:01:38,580 (explosion). 29 00:01:38,682 --> 00:01:43,702 (theme music plays). 30 00:01:54,548 --> 00:01:59,034 Narrator: For four bloody years a nation tears itself 31 00:01:59,136 --> 00:02:02,771 Apart in search of its destiny. 32 00:02:04,675 --> 00:02:07,943 Anna: It was truly americans against americans. 33 00:02:08,712 --> 00:02:14,566 Narrator: Between 1861 and 1865, the union and the confederacy 34 00:02:14,668 --> 00:02:19,872 Are locked in combat across a 2,700 mile border. 35 00:02:21,208 --> 00:02:25,210 But historians now understand that battles on land... 36 00:02:25,312 --> 00:02:28,647 Tell only part of the story. 37 00:02:29,116 --> 00:02:31,466 Craig: The war at sea dramatically affected the 38 00:02:31,569 --> 00:02:33,735 Trajectory of the war. 39 00:02:36,607 --> 00:02:39,641 Narrator: The naval conflict takes place on rivers, lakes 40 00:02:39,760 --> 00:02:42,477 And all along the american coast. 41 00:02:43,013 --> 00:02:46,899 Incredibly, over 2000 civil war wrecks survive. 42 00:02:48,269 --> 00:02:50,769 And one of the most significant lies here 43 00:02:50,871 --> 00:02:53,338 In the waters of virginia. 44 00:02:56,377 --> 00:03:00,379 As the atlantic ocean drains away, 45 00:03:00,548 --> 00:03:04,233 A broken battleship begins to emerge. 46 00:03:05,336 --> 00:03:10,205 The result of a battle that sends shockwaves around the world. 47 00:03:18,949 --> 00:03:22,334 Maritime archaeologist james delgado and historian 48 00:03:22,436 --> 00:03:26,205 Anna gibson holloway are in hampton roads... 49 00:03:26,307 --> 00:03:28,473 Searching for a body. 50 00:03:28,576 --> 00:03:31,243 James: The fact that we are right at the spot. 51 00:03:31,345 --> 00:03:33,512 Anna: It's an amazing scene. 52 00:03:33,614 --> 00:03:36,448 James: Yes, this is a battlefield. 53 00:03:38,202 --> 00:03:42,337 Narrator: They're in a stretch of water, that in March 1862 54 00:03:42,439 --> 00:03:45,207 Is the most dangerous in america. 55 00:03:49,513 --> 00:03:52,781 To the west lies the confederate capital, richmond. 56 00:03:53,417 --> 00:03:56,468 To the north, the union capital, washington dc. 57 00:03:58,639 --> 00:04:02,207 James: It's a critical point and so it is no surprise that 58 00:04:02,309 --> 00:04:04,643 This is going to be the setting for the first great 59 00:04:04,745 --> 00:04:08,080 Naval encounter of the american civil war. 60 00:04:10,050 --> 00:04:13,201 Narrator: The confederates hold most of virginia. 61 00:04:13,954 --> 00:04:17,005 But on the north side of hampton roads a lone union 62 00:04:17,107 --> 00:04:20,208 Fortress is home to a squadron of warships. 63 00:04:22,613 --> 00:04:26,181 One of them is the uss cumberland. 64 00:04:26,317 --> 00:04:29,701 Sleek, fast and armed to the teeth. 65 00:04:30,671 --> 00:04:33,238 When launched, 20 years earlier, she was the most 66 00:04:33,340 --> 00:04:36,408 Powerful ship in the us navy. 67 00:04:38,712 --> 00:04:42,014 But on the evening of March 8th astonishing reports 68 00:04:42,116 --> 00:04:44,833 Reach the union base. 69 00:04:46,737 --> 00:04:51,273 Eyewitnesses describe a strange vessel bearing down on the cumberland. 70 00:04:53,210 --> 00:04:54,810 In minutes... 71 00:04:54,928 --> 00:04:56,578 (cannon fire). 72 00:04:56,680 --> 00:04:59,281 She disappears. 73 00:05:01,935 --> 00:05:05,203 So, what sank her, and how? 74 00:05:10,377 --> 00:05:12,277 Anna: They're going to be going right um, down the 75 00:05:12,379 --> 00:05:15,314 Elizabeth river into the heart of hampton roads. 76 00:05:15,432 --> 00:05:18,734 James: So, they're coming in right here and this where they hit. 77 00:05:18,836 --> 00:05:21,169 Anna: It was such a scramble... 78 00:05:21,672 --> 00:05:23,505 Narrator: James and anna's research is part of a 79 00:05:23,624 --> 00:05:26,908 Comprehensive survey of the underwater landscape here. 80 00:05:31,048 --> 00:05:33,548 But it's not easy. 81 00:05:34,134 --> 00:05:36,468 James: This is very dark water, you've got a river 82 00:05:36,570 --> 00:05:38,837 Coming down to meet the sea, its silty. 83 00:05:38,939 --> 00:05:41,907 You really can't see your hand in front of your face. 84 00:05:46,113 --> 00:05:48,547 Narrator: The team's multi beam sonar fires sound waves 85 00:05:48,649 --> 00:05:51,033 To the sea floor... 86 00:05:51,935 --> 00:05:57,339 Mapping the shape and size of anything on the sea bed in perfect 3-d detail. 87 00:06:02,046 --> 00:06:05,347 Data from the scans begins to appear... 88 00:06:09,103 --> 00:06:12,270 A ghostly outline. 89 00:06:16,176 --> 00:06:17,943 Anna: Just amazing... 90 00:06:18,846 --> 00:06:20,212 So, what are we seeing here? 91 00:06:20,314 --> 00:06:23,281 James: Well we're right over the wreck now. 92 00:06:23,384 --> 00:06:27,936 What we see are the timbers and the more or less intact 93 00:06:28,038 --> 00:06:29,337 Hull of the cumberland. 94 00:06:29,440 --> 00:06:30,806 Anna: So, we're looking at a war grave here. 95 00:06:30,908 --> 00:06:32,641 James: Oh, very much so. 96 00:06:33,310 --> 00:06:36,978 Narrator: To discover what happened here, we can combine 97 00:06:37,081 --> 00:06:41,483 Data from the scans with powerful graphical software 98 00:06:42,903 --> 00:06:47,139 And uncover one of the first naval casualties of the civil war. 99 00:06:51,145 --> 00:06:54,045 An incredible scene emerges. 100 00:06:54,148 --> 00:06:56,415 Corroded ironwork... 101 00:06:56,517 --> 00:06:59,768 Then the twisted remains of a large wooden hull. 102 00:07:03,273 --> 00:07:07,509 Anna: You can still see the outline, the form of cumberland. 103 00:07:10,380 --> 00:07:13,448 James: Articulated wooden timbers, the sides of the ship. 104 00:07:13,550 --> 00:07:16,401 You have this sense of this ship sitting down there, 105 00:07:16,503 --> 00:07:19,171 Shrouded in mud. 106 00:07:26,580 --> 00:07:28,713 Narrator: It's a haunting scene. 107 00:07:28,816 --> 00:07:32,134 But does it contain clues? 108 00:07:33,570 --> 00:07:36,671 There's cannon shot half buried in the mud, 109 00:07:36,773 --> 00:07:39,608 Normal for a battle of this era. 110 00:07:39,910 --> 00:07:43,211 But this isn't normal at all. 111 00:07:44,648 --> 00:07:48,433 Debris spread over 350 feet. 112 00:07:53,073 --> 00:07:55,807 Something much more destructive than cannonballs 113 00:07:55,909 --> 00:07:58,710 Hits the cumberland. 114 00:07:59,513 --> 00:08:03,365 Using contemporary accounts and evidence from the drained wreck, 115 00:08:03,450 --> 00:08:07,035 We can bring an extraordinary moment back to life. 116 00:08:12,342 --> 00:08:15,043 As the cumberland lies at anchor she is suddenly 117 00:08:15,145 --> 00:08:19,181 Challenged by a ship unlike any other. 118 00:08:21,702 --> 00:08:25,937 A ship with no sails, but driven by steam... 119 00:08:26,907 --> 00:08:30,609 A ship covered not in wood, but metal. 120 00:08:30,711 --> 00:08:35,647 The first ever american ironclad: The css virginia. 121 00:08:38,936 --> 00:08:42,070 The confederate ship bristles with weaponry. 122 00:08:42,839 --> 00:08:47,008 Six heavy cannon and four large rifled guns. 123 00:08:52,716 --> 00:08:56,401 It's no surprise that witnesses imagined it; 124 00:08:56,503 --> 00:08:59,437 A horrid creature of a nightmare. 125 00:09:00,207 --> 00:09:02,374 (gunshots). 126 00:09:02,476 --> 00:09:04,843 Craig: They manned the guns and began firing. 127 00:09:04,945 --> 00:09:07,846 Shots would bounce off her side. 128 00:09:08,899 --> 00:09:11,466 Anna: Imagine the horror. 129 00:09:11,568 --> 00:09:14,636 The virginia comes extremely close to cumberland, so close 130 00:09:14,738 --> 00:09:17,939 In fact that the men on board the cumberland recall that 131 00:09:18,041 --> 00:09:22,844 They could hear the taunts and the laughter inside the virginia. 132 00:09:23,847 --> 00:09:25,981 (laughter). 133 00:09:26,083 --> 00:09:28,433 Narrator: Near immune to the cumberland's broadside, 134 00:09:28,535 --> 00:09:32,070 Virginia drives straight at her wooden enemy. 135 00:09:32,539 --> 00:09:35,307 Deploying a tactic more familiar to the roman empire 136 00:09:35,409 --> 00:09:38,443 Than the 19th century. 137 00:09:38,912 --> 00:09:42,013 A huge metal ram. 138 00:09:42,883 --> 00:09:46,001 Her sheer power and momentum do the rest... 139 00:09:49,506 --> 00:09:55,010 The impact is devastating and sends 121 men to their deaths. 140 00:09:59,950 --> 00:10:03,034 Virginia immediately turns her guns onto another union 141 00:10:03,136 --> 00:10:06,938 Warship and smashes it to pieces too. 142 00:10:09,409 --> 00:10:12,243 Craig: It was the most decisive defeat of the union navy 143 00:10:12,346 --> 00:10:16,047 Until pearl harbor so this was an absolute shock. 144 00:10:21,171 --> 00:10:24,239 James: What happens here at that moment is that that type 145 00:10:24,341 --> 00:10:26,908 Of ship is rendered obsolete. 146 00:10:27,010 --> 00:10:30,912 The age of the wooden wall is over, all hail the age of iron. 147 00:10:35,002 --> 00:10:37,302 Narrator: But the confederates aren't the only ones working 148 00:10:37,404 --> 00:10:39,738 On a secret weapon. 149 00:10:39,840 --> 00:10:42,674 The union navy has one too. 150 00:10:47,848 --> 00:10:51,533 This, the uss monitor. 151 00:10:53,603 --> 00:10:56,905 A different kind of ironclad. 152 00:11:01,111 --> 00:11:04,846 The day after the death of cumberland, the two metal warships 153 00:11:04,948 --> 00:11:09,634 Will meet in one of the civil war's defining moments. 154 00:11:11,705 --> 00:11:15,273 As the waters off north carolina begin to drain away, 155 00:11:15,375 --> 00:11:17,809 The wreck of one of these iron monsters 156 00:11:17,911 --> 00:11:20,812 Begins to emerge from the depths. 157 00:11:31,475 --> 00:11:33,742 Narrator: Cape hatteras. 158 00:11:34,244 --> 00:11:38,113 Here off north carolina lies a legend of the civil war, 159 00:11:38,215 --> 00:11:41,132 The uss monitor. 160 00:11:42,135 --> 00:11:45,103 The national oceanic and atmospheric administration, 161 00:11:45,205 --> 00:11:48,406 Or noaa, leads an effort here to discover the secrets 162 00:11:48,508 --> 00:11:51,342 Of this revolutionary warship. 163 00:11:56,016 --> 00:12:00,502 The story of the monitor has long been clouded by wartime propaganda. 164 00:12:04,341 --> 00:12:07,609 The team hopes the wreck can provide the truth. 165 00:12:12,649 --> 00:12:15,400 Underwater filming only shows a fraction of what's spread 166 00:12:15,502 --> 00:12:18,169 Across the sea floor. 167 00:12:21,208 --> 00:12:25,577 But using decades of carefully gathered data, we can now 168 00:12:25,679 --> 00:12:29,280 Drain the atlantic ocean away to uncover the last 169 00:12:29,382 --> 00:12:33,435 Resting place of america's second ironclad. 170 00:12:36,306 --> 00:12:38,139 Emerging into view, 171 00:12:38,241 --> 00:12:41,476 All that remains of a ground-breaking warship. 172 00:12:51,571 --> 00:12:54,005 Like a drowned alien being, 173 00:12:54,107 --> 00:12:58,276 The monitor lies upside down, her hull in pieces, 174 00:12:58,645 --> 00:13:02,180 Clearly made of metal, just like the css virginia 175 00:13:02,282 --> 00:13:04,632 With a thick belt of armor. 176 00:13:04,734 --> 00:13:07,869 James: The distinctive form of the iron armor belt is still there, 177 00:13:07,971 --> 00:13:11,005 The tip of the bow is sharply defined. 178 00:13:12,576 --> 00:13:16,211 Right there is the grave of the iconic warship of the 179 00:13:16,313 --> 00:13:18,713 American civil war. 180 00:13:25,372 --> 00:13:27,372 Narrator: The monitor's greatest challenge comes in 181 00:13:27,474 --> 00:13:32,610 Hampton roads, when she confronts the css virginia, 182 00:13:34,381 --> 00:13:38,399 Just a day after the confederate ship destroys the cumberland. 183 00:13:41,872 --> 00:13:44,572 To find out how monitor fought that day, 184 00:13:44,674 --> 00:13:49,077 Maritime archaeologists carefully bring key parts of her to the surface. 185 00:13:51,281 --> 00:13:54,315 Their most important target? 186 00:13:55,602 --> 00:13:59,137 The first gun turret ever used in combat. 187 00:14:04,010 --> 00:14:07,178 James: The recovery of the turret was an incredible 188 00:14:07,280 --> 00:14:11,566 Undertaking and in that, what was discovered was a time capsule. 189 00:14:15,572 --> 00:14:19,774 Narrator: It is analyzed at the baton conservation laboratory, in virginia. 190 00:14:19,876 --> 00:14:21,442 Will: That way. 191 00:14:21,545 --> 00:14:23,811 If you consider the story of monitor like a puzzle. 192 00:14:23,914 --> 00:14:27,348 It's easy to get the outside edges of the puzzle because 193 00:14:27,450 --> 00:14:30,935 You can use historical record, but understanding the exact story, 194 00:14:31,037 --> 00:14:34,572 That's where the archaeology and conservation comes in. 195 00:14:36,643 --> 00:14:40,011 Narrator: They discover that the turret is 21 feet across, 196 00:14:40,113 --> 00:14:44,299 9 feet high and wrapped in 8 inches of armor. 197 00:14:45,669 --> 00:14:49,037 Thicker than on any other ship afloat, including its rival, 198 00:14:49,139 --> 00:14:52,140 The css virginia. 199 00:14:53,443 --> 00:14:55,977 Researchers scan the turret using lasers 200 00:14:56,079 --> 00:14:59,180 Looking for battle damage... 201 00:15:01,468 --> 00:15:06,771 And find evidence of confederate fire, 202 00:15:06,873 --> 00:15:11,509 But also proof that monitor's armor keeps it out. 203 00:15:15,081 --> 00:15:18,666 Inside the turret; two gun mounts. 204 00:15:21,571 --> 00:15:24,505 Armed with these new findings from the laboratory we can 205 00:15:24,608 --> 00:15:28,343 Return to the drained landscape below the atlantic. 206 00:15:30,480 --> 00:15:34,115 And use computer graphics to lift the wreck of the monitor 207 00:15:34,217 --> 00:15:37,135 From the sea bed... 208 00:15:37,237 --> 00:15:41,873 Turn her right side up and replace her turret. 209 00:15:44,344 --> 00:15:47,712 Now this ingenious technology can be seen operating as its 210 00:15:47,814 --> 00:15:50,615 Designers intended. 211 00:15:51,701 --> 00:15:53,768 The turret sits on a brass ring, 212 00:15:53,870 --> 00:15:57,071 Allowing it to rotate 360 degrees. 213 00:15:58,174 --> 00:16:00,875 At a time when guns are typically fixed... 214 00:16:01,044 --> 00:16:05,346 This instant maneuverability gives the union sailors a huge advantage. 215 00:16:07,617 --> 00:16:10,401 As does the second gun. 216 00:16:11,371 --> 00:16:13,004 When one fires... 217 00:16:13,106 --> 00:16:16,858 The other moves back inside the turret to be reloaded. 218 00:16:18,511 --> 00:16:21,079 Will: So, they would just switch between the guns. 219 00:16:22,082 --> 00:16:24,182 Narrator: So how does the monitor compare with the 220 00:16:24,284 --> 00:16:27,035 All-conquering virginia? 221 00:16:30,907 --> 00:16:35,009 At first sight, the favorite seems to be the confederate ship. 222 00:16:36,413 --> 00:16:39,947 She's over 100 feet longer than the monitor with 10 huge 223 00:16:40,050 --> 00:16:43,568 Guns compared to the monitor's two... 224 00:16:43,903 --> 00:16:47,171 And four-inch thick steel armor, although her fearsome 225 00:16:47,273 --> 00:16:50,675 Ram was lost when she sank the cumberland. 226 00:16:52,812 --> 00:16:55,813 In contrast, the monitor appears puny. 227 00:16:55,915 --> 00:16:59,934 But she's faster and has even thicker armour on her turret. 228 00:17:03,139 --> 00:17:05,873 And, although she only carries two guns, 229 00:17:05,975 --> 00:17:08,776 They are superbly maneuverable. 230 00:17:12,215 --> 00:17:15,266 March 9th, 1862. 231 00:17:15,735 --> 00:17:19,670 A day after sinking the cumberland, 232 00:17:22,308 --> 00:17:25,710 The virginia still threatens the union fleet. 233 00:17:27,347 --> 00:17:30,882 So, the monitor is unleashed to challenge her. 234 00:17:35,071 --> 00:17:38,506 In command is lieutenant john worden. 235 00:17:40,176 --> 00:17:43,044 Anna: There was fear. 236 00:17:43,146 --> 00:17:47,782 The men on the monitor recall an overwhelming feeling of silence. 237 00:17:51,037 --> 00:17:52,970 Will: It's like the astronauts going into space, it's the 238 00:17:53,073 --> 00:17:55,506 First time they did it, so sure there's fear but at the 239 00:17:55,608 --> 00:17:58,209 Same time, you're on the cutting edge. 240 00:17:58,311 --> 00:18:00,178 Captain: Fire. 241 00:18:03,083 --> 00:18:06,801 Narrator: John worden's turret guns follow his enemy's every move... 242 00:18:06,903 --> 00:18:10,905 (gunshots). 243 00:18:11,007 --> 00:18:13,641 Firing shot after shot. 244 00:18:16,045 --> 00:18:19,347 But virginia's armor does its job. 245 00:18:21,084 --> 00:18:24,802 Monitor's shots bounce into the water. 246 00:18:25,805 --> 00:18:29,373 For four hours, the ironclads duke it out... 247 00:18:29,476 --> 00:18:32,944 Each failing to land a decisive blow. 248 00:18:33,046 --> 00:18:36,047 Until a lucky shot from virginia manages to injure 249 00:18:36,132 --> 00:18:38,166 The monitor's commander. 250 00:18:38,268 --> 00:18:41,335 Anna: The pilot house is struck by one of the virginia's guns. 251 00:18:43,106 --> 00:18:44,472 Sailor: Sir! 252 00:18:44,574 --> 00:18:47,508 Anna: Immediately john worden is temporarily blinded. 253 00:18:48,511 --> 00:18:51,512 There is sudden chaos on board monitor because he falls back 254 00:18:51,614 --> 00:18:54,148 And says I am blind I'm blind. 255 00:18:56,769 --> 00:19:00,171 Narrator: Monitor withdraws for a damage report. 256 00:19:00,473 --> 00:19:04,275 When she returns, she finds the battlefield empty. 257 00:19:05,345 --> 00:19:08,679 Virginia, also damaged, has returned to her base. 258 00:19:10,116 --> 00:19:15,469 Anna: Neither could figure out how to kill the other vessel. 259 00:19:16,606 --> 00:19:19,407 It was likely a draw. 260 00:19:20,376 --> 00:19:22,877 Narrator: But by stopping virginia's killing spree, 261 00:19:22,979 --> 00:19:25,913 Monitor becomes the most celebrated warship in the 262 00:19:26,015 --> 00:19:28,266 Northern states. 263 00:19:29,836 --> 00:19:33,471 James: It is the ship that has saved the union. 264 00:19:34,207 --> 00:19:35,973 It becomes an icon. 265 00:19:36,075 --> 00:19:38,809 It is a symbol of national pride. 266 00:19:41,548 --> 00:19:43,981 Narrator: The battle of the two metal monsters fascinates 267 00:19:44,083 --> 00:19:47,835 The world but they never fight again. 268 00:19:48,738 --> 00:19:52,773 Two months later, union troops close in on virginia's home-port. 269 00:19:53,743 --> 00:19:56,711 To keep her out of enemy hands, her own crew 270 00:19:56,813 --> 00:19:59,347 Sends her to the bottom. 271 00:20:03,603 --> 00:20:06,737 The fate of the monitor is more tragic. 272 00:20:07,740 --> 00:20:10,357 Nine months after fighting virginia, 273 00:20:10,443 --> 00:20:12,710 She's off cape hatteras, north carolina, 274 00:20:12,812 --> 00:20:15,680 Under tow by another union ship. 275 00:20:17,483 --> 00:20:20,034 It's a notoriously rough patch of sea known as 276 00:20:20,136 --> 00:20:23,304 'the graveyard of the atlantic'. 277 00:20:24,774 --> 00:20:27,675 Out of nowhere, a storm hits. 278 00:20:28,244 --> 00:20:31,112 Anna: Monitor sailed right into this maelstrom. 279 00:20:32,882 --> 00:20:35,700 Narrator: The waves badly damage her structure. 280 00:20:35,802 --> 00:20:38,769 Water rushes into the hull. 281 00:20:39,772 --> 00:20:43,441 The sheer weight of monitor's armor does the rest. 282 00:20:47,013 --> 00:20:49,180 Will: It is kind of ironic that there's a potential that 283 00:20:49,282 --> 00:20:52,400 What was meant to keep the monitor crew safe could have 284 00:20:52,502 --> 00:20:55,469 Been its ultimate undoing. 285 00:20:58,308 --> 00:21:02,310 Anna: The distress signal was a red signal lantern, and it 286 00:21:02,412 --> 00:21:06,047 Would appear and disappear and then appear again and 287 00:21:06,149 --> 00:21:10,334 Disappear and this, this went on for a while until finally 288 00:21:10,436 --> 00:21:14,372 It appeared and was seen no more. 289 00:21:17,844 --> 00:21:20,578 Narrator: Despite frantic rescue attempts, the monitor 290 00:21:20,680 --> 00:21:23,881 Takes 16 men down with her. 291 00:21:26,302 --> 00:21:30,504 Nearly a century and a half later, navy divers recover the 292 00:21:30,606 --> 00:21:34,675 Remains of two sailors from inside the turret. 293 00:21:37,447 --> 00:21:42,366 They are buried with full military honors at arlington national cemetery. 294 00:21:43,770 --> 00:21:48,072 James: For a brief moment, the entire country stood united, 295 00:21:48,174 --> 00:21:52,443 Long after the passions of that war, to honor these two men, 296 00:21:52,545 --> 00:21:56,280 Who had come back to us from the depths and from 297 00:21:56,382 --> 00:21:58,799 The turret of the monitor. 298 00:22:01,304 --> 00:22:04,071 Narrator: The epic battle of the ironclads points the way 299 00:22:04,173 --> 00:22:06,474 To the future. 300 00:22:06,576 --> 00:22:11,178 The union navy builds 64 new monitor-class ships 301 00:22:11,280 --> 00:22:16,300 During the next two years and on the confederate side, 302 00:22:16,402 --> 00:22:19,070 The idea of metal warships 303 00:22:19,172 --> 00:22:22,673 Is taken a decisive and deadly step further. 304 00:22:24,277 --> 00:22:27,712 As the waters of charleston harbor begin to empty, the 305 00:22:27,814 --> 00:22:31,832 Shattered remains of another lost union warship come into view. 306 00:22:33,302 --> 00:22:37,271 The result of a terrifying new confederate weapon. 307 00:22:47,383 --> 00:22:51,268 Narrator: Maritime archaeologist michael scafuri is investigating 308 00:22:51,371 --> 00:22:54,372 One of the civil war's greatest mysteries 309 00:22:54,474 --> 00:22:57,608 Outside charleston harbor, south carolina. 310 00:22:58,778 --> 00:23:00,561 Michael: People were fascinated by the story and 311 00:23:00,646 --> 00:23:03,214 Wanted to find out more. 312 00:23:03,950 --> 00:23:05,900 To really understand what happened we needed to 313 00:23:06,002 --> 00:23:08,936 Investigate from an archaeological point of view. 314 00:23:10,339 --> 00:23:13,941 There are secrets still left to be discovered. 315 00:23:15,011 --> 00:23:19,880 Narrator: In February 1864, charleston is a confederate stronghold. 316 00:23:22,068 --> 00:23:23,934 Craig: South carolina was perceived as the heart and 317 00:23:24,036 --> 00:23:26,670 Soul of the rebellion and charleston itself was the 318 00:23:26,773 --> 00:23:29,039 Black heart of that rebellion. 319 00:23:29,158 --> 00:23:32,009 Narrator: It's being blockaded by a squadron of 20 union 320 00:23:32,111 --> 00:23:34,945 Warships, including six ironclads... 321 00:23:36,048 --> 00:23:39,667 Part of a plan to squeeze the south economically. 322 00:23:42,472 --> 00:23:46,540 One of them is the uss housatonic. 323 00:23:47,844 --> 00:23:51,011 Made of wood but powered by steam, she is one of the 324 00:23:51,114 --> 00:23:54,615 Union's most heavily armed ships. 325 00:23:57,370 --> 00:24:02,506 On February 17th, at 8:40 pm, the bay is calm. 326 00:24:04,744 --> 00:24:07,244 Suddenly there is a huge explosion... 327 00:24:07,346 --> 00:24:09,346 (explosion). 328 00:24:11,567 --> 00:24:14,802 The housatonic is gone. 329 00:24:14,904 --> 00:24:18,472 The only clue: Eyewitness reports of a dark shape 330 00:24:18,574 --> 00:24:21,208 Moving in the water. 331 00:24:25,481 --> 00:24:29,166 Michael scafuri knows where the housatonic lies, 332 00:24:29,268 --> 00:24:33,237 Now he wants to understand what happened to it. 333 00:24:34,941 --> 00:24:38,826 But in these turbulent seas, visibility is nearly zero and 334 00:24:38,911 --> 00:24:42,346 Underwater photography very difficu. 335 00:24:44,116 --> 00:24:47,268 So powerful sonar probes the seabed. 336 00:24:49,505 --> 00:24:52,439 Using this and other data, it's possible to see what no 337 00:24:52,542 --> 00:24:56,043 Diver ever could and drain away the atlantic 338 00:24:56,145 --> 00:24:59,580 To uncover an iconic wreck. 339 00:25:03,436 --> 00:25:07,471 First, two iron water tanks emerge... 340 00:25:08,941 --> 00:25:12,843 Next broken timbers, half-hidden in the sediment 341 00:25:13,346 --> 00:25:19,166 But then, blowing away the silt uncovers the seabed of 1864. 342 00:25:24,140 --> 00:25:26,840 And here she is... 343 00:25:26,943 --> 00:25:30,611 The remains of the uss housatonic. 344 00:25:32,481 --> 00:25:36,901 Whatever fate she suffered has been erased by the ravages of time. 345 00:25:38,170 --> 00:25:42,106 Even fully revealed there are almost no clues. 346 00:25:43,843 --> 00:25:47,978 But what if we could return to the moment just before she sinks? 347 00:25:50,516 --> 00:25:56,370 By combining historical salvage records, and survey data we can. 348 00:26:00,076 --> 00:26:04,378 Rebuilding the housatonic exactly as she was. 349 00:26:06,082 --> 00:26:10,401 A towering fighting warship in perfect condition... 350 00:26:13,239 --> 00:26:16,941 Except for this! 351 00:26:19,645 --> 00:26:24,882 A hole in the hull deep below the water line. 352 00:26:28,504 --> 00:26:32,873 This is still the age of the cannon ball and they usually 353 00:26:32,975 --> 00:26:37,177 Shatter masts and punch holes above the waterline. 354 00:26:38,080 --> 00:26:41,582 So, what caused this fatal wound? 355 00:26:43,102 --> 00:26:45,703 For over a century, archaeologists scour 356 00:26:45,805 --> 00:26:48,872 The area around the wreck site. 357 00:26:52,745 --> 00:26:57,481 And eventually, about 1,000 feet from the wreck... 358 00:26:58,467 --> 00:27:01,368 They find this. 359 00:27:08,277 --> 00:27:12,880 The team recovers the remains and when they get them ashore they realize. 360 00:27:18,437 --> 00:27:20,504 They've found the confederate's first 361 00:27:20,606 --> 00:27:22,773 Operational submarine... 362 00:27:22,875 --> 00:27:25,976 The hl hunley. 363 00:27:27,580 --> 00:27:31,348 And it is what took the housatonic down. 364 00:27:37,807 --> 00:27:41,008 In the warren lasch conservation center in charleston, 365 00:27:41,110 --> 00:27:44,812 Michael scafuri and his team pour over every inch. 366 00:27:45,748 --> 00:27:47,815 Michael: The techniques you use to investigate a site, 367 00:27:47,917 --> 00:27:51,001 Are very much like a crime scene investigation. 368 00:27:51,103 --> 00:27:55,572 You record everything and then you try and use that evidence 369 00:27:55,675 --> 00:27:58,308 To figure out what happened here. 370 00:28:07,103 --> 00:28:10,738 It was a product of the american civil war and spurred 371 00:28:10,840 --> 00:28:14,007 On by the needs of that war to develop new technologies. 372 00:28:16,879 --> 00:28:20,481 Narrator: First question, how did it move? 373 00:28:22,001 --> 00:28:25,736 The archaeologists find no sign of an engine. 374 00:28:26,939 --> 00:28:30,874 But they do find this... 375 00:28:31,944 --> 00:28:34,912 Johanna: This is a wrought iron crank and that's how they 376 00:28:35,014 --> 00:28:36,580 Moved the submarine. 377 00:28:36,682 --> 00:28:38,465 They hand-crank it. 378 00:28:38,567 --> 00:28:42,069 The hand crank moved a flywheel, the flywheel moved a 379 00:28:42,171 --> 00:28:46,106 Series of mechanisms, and then that moves the propeller. 380 00:28:48,577 --> 00:28:52,846 Narrator: Next, how did the crew breathe underwater? 381 00:28:54,283 --> 00:28:57,768 There's no evidence of any way to refresh the air... 382 00:28:57,870 --> 00:29:02,406 Which means that eight men crammed into this metal tube 383 00:29:02,508 --> 00:29:06,677 Must rely solely on the air already inside. 384 00:29:09,215 --> 00:29:13,534 The team calculates that there's enough oxygen for just two hours. 385 00:29:13,936 --> 00:29:17,604 Severely limiting their range of operations. 386 00:29:19,041 --> 00:29:22,342 Finally, the most important question of all? 387 00:29:22,445 --> 00:29:26,680 Just how did this hand-cranked short-range submarine manage 388 00:29:26,782 --> 00:29:30,601 To ambush and destroy such a powerful enemy? 389 00:29:41,080 --> 00:29:43,580 Narrator: The confederacy's ground-breaking submarine, 390 00:29:43,682 --> 00:29:46,033 The hl hunley. 391 00:29:47,803 --> 00:29:50,471 Inside, there's no sign of a weapons system. 392 00:29:52,408 --> 00:29:55,309 But outside, it's a different story. 393 00:29:57,980 --> 00:30:00,247 Johanna: We have clues all over the submarine that tell 394 00:30:00,349 --> 00:30:02,633 Us what happened. 395 00:30:03,969 --> 00:30:06,403 This is the spar, it was attached to the bow of the 396 00:30:06,505 --> 00:30:09,072 Submarine, the lower part of the submarine. 397 00:30:09,875 --> 00:30:13,243 Narrator: The 16-feet long spar presents a puzzle. 398 00:30:16,215 --> 00:30:19,633 Michael scafuri thinks it isn't a weapon itself... 399 00:30:19,735 --> 00:30:24,671 But the delivery mechanism for a weapon and that weapon 400 00:30:24,773 --> 00:30:27,875 Is an underwater bomb. 401 00:30:30,412 --> 00:30:35,499 In the civil war, they call such weapons by a very modern name, torpedo. 402 00:30:37,002 --> 00:30:39,169 James: In the 21st centu we think of a torpedo as 403 00:30:39,271 --> 00:30:41,972 Something that fires out of the submarine, when originally 404 00:30:42,074 --> 00:30:45,576 Invented in the early 19th century the torpedo was an 405 00:30:45,678 --> 00:30:48,312 Underwater explosive charge. 406 00:30:49,381 --> 00:30:51,748 Narrator: If this is how the hunley attacked, then she 407 00:30:51,851 --> 00:30:55,302 Would need to get within touching distance of her prey. 408 00:30:55,571 --> 00:30:57,838 But how exactly? 409 00:31:00,910 --> 00:31:04,011 For years, historians believe the rebel submariners 410 00:31:04,113 --> 00:31:07,147 Physically attach the bomb, with a barbed spike then 411 00:31:07,249 --> 00:31:10,434 Detonate it from a safe distance. 412 00:31:11,170 --> 00:31:14,271 But other evidence found near the wreck site suggests that 413 00:31:14,373 --> 00:31:17,407 This isn't what happened. 414 00:31:18,744 --> 00:31:21,745 A copper sleeve, which looks like it was created to hold 415 00:31:21,847 --> 00:31:25,015 The explosive in place. 416 00:31:26,435 --> 00:31:29,236 Michael: The copper sleeve was peeled back from the force of 417 00:31:29,338 --> 00:31:33,073 The explosion, clearly showing us that the torpedo was in 418 00:31:33,175 --> 00:31:36,777 Fact on the end of the spar when it went off. 419 00:31:43,335 --> 00:31:45,168 Narrator: Based on the evidence from the drained 420 00:31:45,271 --> 00:31:48,639 Wreck and work in the laboratory it's now possible 421 00:31:48,741 --> 00:31:51,942 To piece together what likely happened. 422 00:31:57,716 --> 00:32:00,334 The confederates are desperate to smash the union's naval 423 00:32:00,502 --> 00:32:02,903 Blockade of charleston. 424 00:32:03,672 --> 00:32:05,839 Craig: The confederacy, because they knew they were 425 00:32:05,941 --> 00:32:08,609 Inferior in the conventional weapons of war, had to turn to 426 00:32:08,711 --> 00:32:11,278 New, creative devices. 427 00:32:12,481 --> 00:32:18,669 James: You try to out-smart the enemy, you try to out-innovate the enemy. 428 00:32:26,912 --> 00:32:29,646 Narrator: The housatonic lies at anchor. 429 00:32:33,202 --> 00:32:36,970 Suddenly, the crew spot a ghostly shape. 430 00:32:39,908 --> 00:32:42,309 Michael: They weren't entirely sure what it was at first. 431 00:32:42,411 --> 00:32:45,912 It looked like a log on the water, maybe a porpoise. 432 00:32:47,249 --> 00:32:49,700 Narrator: In fact the hand-cranked submarine 433 00:32:49,802 --> 00:32:52,636 Is headed straight for the union warship. 434 00:32:53,172 --> 00:32:55,339 Michael: Something like this had never been seen by the 435 00:32:55,441 --> 00:32:58,575 Crew before they would have been terrified. 436 00:32:59,178 --> 00:33:01,578 Narrator: Historians don't know if the hunley's crew tries 437 00:33:01,680 --> 00:33:04,815 To attach their bomb and escape... 438 00:33:04,917 --> 00:33:09,269 But they do know that with the hunley just 16 feet from its prey. 439 00:33:10,105 --> 00:33:12,873 (explosion). 440 00:33:14,309 --> 00:33:18,478 The torpedo does its fatal work and the housatonic 441 00:33:18,580 --> 00:33:21,682 Sinks in minutes. 442 00:33:22,668 --> 00:33:26,670 A new age of naval warfare has begun. 443 00:33:26,772 --> 00:33:29,573 James: Hunley proves to be the first submarine ever to 444 00:33:29,675 --> 00:33:33,210 Sink an enemy warship in combat. 445 00:33:34,646 --> 00:33:37,647 Narrator: But there's a final mystery here. 446 00:33:37,750 --> 00:33:40,567 The hunley never returns to its base. 447 00:33:40,669 --> 00:33:44,137 No-one has ever been sure why. 448 00:33:46,375 --> 00:33:49,025 Michael: With the discovery of the h l hunley a great mystery 449 00:33:49,111 --> 00:33:50,911 Had been solved. 450 00:33:51,013 --> 00:33:54,381 However, the real work begins with discovery, we could then 451 00:33:54,483 --> 00:33:58,468 Begin to investigate from an archaeological point of view. 452 00:33:59,838 --> 00:34:02,506 Narrator: The most obvious explanation... 453 00:34:04,109 --> 00:34:07,644 The hunley is destroyed by her own bomb. 454 00:34:09,214 --> 00:34:11,181 (explosion). 455 00:34:13,035 --> 00:34:16,169 Ken nahshon is a us navy engineer; 456 00:34:16,271 --> 00:34:19,806 His job is to test underwater explosives. 457 00:34:20,275 --> 00:34:22,342 Ken: It's been a historical mystery for well over 458 00:34:22,444 --> 00:34:25,278 100 years and really people have always wondered 459 00:34:25,380 --> 00:34:27,214 What happened to it. 460 00:34:27,316 --> 00:34:30,400 Narrator: How big is the blast and what damage could it have 461 00:34:30,502 --> 00:34:32,836 Done to the hunley? 462 00:34:32,938 --> 00:34:37,541 Ken: We constructed a full-scale replica of hunley's torpedo, 463 00:34:37,643 --> 00:34:41,545 Filled the torpedo with black powder that matches 464 00:34:41,647 --> 00:34:45,465 The black powder used at the time and then set off the explosion. 465 00:34:47,436 --> 00:34:51,037 (explosion). 466 00:34:54,510 --> 00:34:58,044 Narrator: Packed with 135 pounds of gunpowder... 467 00:34:58,147 --> 00:35:03,467 The torpedo is seriously powerful, but the results are unexpected. 468 00:35:06,789 --> 00:35:08,939 Ken: Once the explosion goes off, it generates a 469 00:35:09,041 --> 00:35:11,975 High-pressure wave emanating from the explosion, 470 00:35:12,077 --> 00:35:13,977 As well as a bubble. 471 00:35:14,079 --> 00:35:16,513 That bubble expands and contracts what would happen 472 00:35:16,615 --> 00:35:19,166 Is a high velocity jet would occur, where basically the 473 00:35:19,268 --> 00:35:22,936 Bottom of the bubble comes in on itself and forms this high 474 00:35:23,038 --> 00:35:25,505 Velocity water column that would have punched a hole 475 00:35:25,607 --> 00:35:28,341 Right through housatonic, while leaving hunley 476 00:35:28,443 --> 00:35:31,044 Completely unaffected. 477 00:35:31,146 --> 00:35:33,547 Ken: The most surprising conclusion we had was the 478 00:35:33,649 --> 00:35:36,666 Submarine heaved quite substantially... 479 00:35:37,436 --> 00:35:41,571 However, it was not substantial enough to cause injury. 480 00:35:41,673 --> 00:35:43,874 Narrator: And there is other evidence that 481 00:35:43,976 --> 00:35:46,943 Hunley survives the explosion... 482 00:35:48,347 --> 00:35:51,781 The bodies of all eight crewmen found by archaeologists 483 00:35:51,884 --> 00:35:57,037 Inside the wreck in an excellent state of preservation. 484 00:35:58,640 --> 00:36:01,241 Before they are removed for burial, they are scanned, 485 00:36:01,343 --> 00:36:04,377 Photographed and analyzed. 486 00:36:06,281 --> 00:36:09,866 Michael: We have their remains and we didn't find any injury to the crew. 487 00:36:10,202 --> 00:36:13,837 Narrator: So, if the explosion didn't kill them, what did? 488 00:36:15,741 --> 00:36:19,543 Could the pressure wave have cracked the hull causing flooding? 489 00:36:20,179 --> 00:36:22,512 The evidence suggests not. 490 00:36:22,614 --> 00:36:24,047 Michael: There was no sign of panic on board. 491 00:36:24,149 --> 00:36:25,482 No-one is out of position, 492 00:36:25,567 --> 00:36:27,334 Nobody tried to climb over their neighbor 493 00:36:27,436 --> 00:36:30,503 And you would expect that in a drowning scenario. 494 00:36:31,240 --> 00:36:32,973 Narrator: Michael scafuri believes that there could 495 00:36:33,075 --> 00:36:36,009 Be anotherxplanation. 496 00:36:36,678 --> 00:36:38,478 Michael: There's a strong case to be made for them simply 497 00:36:38,580 --> 00:36:41,064 Staying on the bottom too long, miscalculated how much 498 00:36:41,149 --> 00:36:44,467 Air they had and uh simply went to sleep, 499 00:36:44,570 --> 00:36:47,070 Not to wake up again. 500 00:36:48,140 --> 00:36:51,174 Narrator: Today, the investigation continues. 501 00:36:52,578 --> 00:36:55,512 Johanna: How they were able to hand crank a submarine 502 00:36:55,614 --> 00:36:59,299 Four miles attack a big ship. 503 00:36:59,401 --> 00:37:01,735 The fact that they thought they could do it and they 504 00:37:01,837 --> 00:37:04,971 Did it, that's, that's a most remarkable thing. 505 00:37:08,277 --> 00:37:10,977 Narrator: In charleston's magnolia cemetery, 506 00:37:11,079 --> 00:37:14,514 A poignant memorial to a pioneering crew. 507 00:37:16,702 --> 00:37:18,535 Michael: The fate of the hunley crew was a mystery 508 00:37:18,637 --> 00:37:22,021 For 136 years, so it was appropriate for them to 509 00:37:22,107 --> 00:37:24,441 Eventually be given a proper burial after 510 00:37:24,543 --> 00:37:28,678 136 years of being lost at sea. 511 00:37:29,982 --> 00:37:32,565 This is an archaeologic project but this is also the 512 00:37:32,634 --> 00:37:35,635 Story of a number of people... 513 00:37:36,004 --> 00:37:38,238 8 crew in hunley and five on housatonic who lost their 514 00:37:38,340 --> 00:37:42,208 Lives and it's important that we get their stories straight. 515 00:37:46,565 --> 00:37:49,933 Narrator: The world's first successful fighting submarine... 516 00:37:50,636 --> 00:37:52,435 (explosion). 517 00:37:52,537 --> 00:37:56,172 Is at the forefront of a civil war arms race. 518 00:37:58,977 --> 00:38:03,246 Draining the oceans around mobile, alabama, 519 00:38:04,449 --> 00:38:07,434 Reveals astonishing evidence 520 00:38:08,503 --> 00:38:11,338 That the race isn't over yet. 521 00:38:24,736 --> 00:38:27,871 Narrator: By 1864, two years after the game-changing 522 00:38:27,973 --> 00:38:30,440 Development of the monitor... 523 00:38:31,243 --> 00:38:34,711 This is the face of naval warfare. 524 00:38:34,813 --> 00:38:38,014 The uss tecumseh. 525 00:38:38,283 --> 00:38:41,534 A bigger, better ironclad. 526 00:38:42,337 --> 00:38:45,405 Designed to be impregnable to enemy fire, 527 00:38:45,507 --> 00:38:48,408 It's 50 feet longer than the monitor, 528 00:38:48,510 --> 00:38:52,946 Has thicker armor and two massive 15-inch guns. 529 00:38:56,635 --> 00:39:01,304 Tecumseh is one of 4 ironclads in a fleet of 18 union warships. 530 00:39:04,209 --> 00:39:07,777 Their target is mobile bay, alabama. 531 00:39:07,879 --> 00:39:10,914 One of the last confederate ports in the south. 532 00:39:13,769 --> 00:39:17,303 If the union can capture it, the war could be over soon. 533 00:39:20,809 --> 00:39:23,643 As the fleet enters the bay, there's an explosion... 534 00:39:24,212 --> 00:39:26,212 (explosion). 535 00:39:26,314 --> 00:39:29,766 And the mighty tecumseh is hit. 536 00:39:30,769 --> 00:39:34,270 Almost all her crew are lost. 537 00:39:36,308 --> 00:39:40,310 The only union ironclad ever sunk in battle. 538 00:39:47,035 --> 00:39:51,071 Maritime archaeologist james delgado is in mobile bay, 539 00:39:51,173 --> 00:39:55,308 Studying the wreck of tecumseh and trying to work out what sank her. 540 00:39:56,778 --> 00:39:59,112 James: There are still amazing secretbeneath the waters of 541 00:39:59,214 --> 00:40:01,548 Mobile bay that most people don't see... 542 00:40:02,467 --> 00:40:05,168 Sunken vessels lost in the battle. 543 00:40:06,605 --> 00:40:10,140 Narrator: The team prepares to use side scan sonar and a 544 00:40:10,242 --> 00:40:13,977 Magnetometer to probe the seafloor. 545 00:40:15,080 --> 00:40:17,113 Anna: Ready? 546 00:40:21,002 --> 00:40:23,536 James: Okay, so we're in, what altitude are we flying the head at? 547 00:40:23,638 --> 00:40:25,705 Crew: We're about 15 feet off the bottom. 548 00:40:25,807 --> 00:40:28,241 James: Okay and speed's running at about? 549 00:40:28,343 --> 00:40:30,610 Crew: At about 4 knots. James: Yeah, good. 550 00:40:30,712 --> 00:40:32,645 Crew: Returns looking smooth. 551 00:40:32,747 --> 00:40:35,248 James: Whoa, whoa, whoa okay, what are we coming up on here? 552 00:40:35,350 --> 00:40:37,801 Crew: Does that look like something? 553 00:40:37,903 --> 00:40:41,171 There we go, I think we might have a shipwreck. 554 00:40:41,606 --> 00:40:43,740 James: We're on it. 555 00:40:43,842 --> 00:40:47,377 Narrator: The scanner detects a large iron object. 556 00:40:47,479 --> 00:40:49,612 It's in the right place. 557 00:40:49,681 --> 00:40:52,415 James is convinced it's tecumseh! 558 00:40:55,704 --> 00:40:58,805 James: But there's a lot of mud here, looks like given 559 00:40:58,907 --> 00:41:02,509 Stuff coming on it, I think this thing's buried. 560 00:41:03,545 --> 00:41:06,028 Narrator: The mud and silt of 130 years 561 00:41:06,114 --> 00:41:08,248 Obscures much of the wreck. 562 00:41:08,350 --> 00:41:12,302 Only emptying mobile bay of water can reveal 563 00:41:12,404 --> 00:41:15,038 What's really down there. 564 00:41:15,140 --> 00:41:18,975 And using the expedition data we can do just that to try and 565 00:41:19,077 --> 00:41:23,880 Solve one of the final mysteries of the american civil war. 566 00:41:26,835 --> 00:41:29,235 As the water drains away... 567 00:41:29,337 --> 00:41:32,572 A tantalizing sight emerges... 568 00:41:32,674 --> 00:41:36,109 A section of an iron hull buried in the seabed... 569 00:41:36,978 --> 00:41:38,878 And based on the survey data, 570 00:41:38,980 --> 00:41:41,548 We can drain away the mud as well. 571 00:41:46,137 --> 00:41:47,637 Underneath... 572 00:41:47,739 --> 00:41:49,672 An incredible sight. 573 00:41:49,774 --> 00:41:54,210 A massive iron monster, 223 feet long 574 00:41:55,280 --> 00:41:57,747 Lying upside down. 575 00:41:57,849 --> 00:42:01,367 Its spine slowly corroding away. 576 00:42:02,304 --> 00:42:05,371 Once one of the world's most powerful vessels, 577 00:42:05,473 --> 00:42:08,308 The pride of the union fleet... 578 00:42:08,410 --> 00:42:11,911 Now seen in the clear light of day for the first time 579 00:42:12,013 --> 00:42:15,348 In over 150 years. 580 00:42:17,802 --> 00:42:21,437 A closer look reveals a clue. 581 00:42:23,141 --> 00:42:26,342 Under the waterline, a large dent in the hull, 582 00:42:26,444 --> 00:42:29,879 8 feet long and 5 feet wide 583 00:42:32,851 --> 00:42:35,435 And more evidence... 584 00:42:36,638 --> 00:42:41,140 Metal seams split apart, broken with explosive force. 585 00:42:44,296 --> 00:42:48,381 So, could it be the victim of another confederate submarine? 586 00:42:52,871 --> 00:42:56,606 Union spies reported rebel subs under construction, 587 00:42:56,708 --> 00:43:00,577 But there are no records of them being active here. 588 00:43:02,047 --> 00:43:05,248 What else might have caused it? 589 00:43:05,684 --> 00:43:08,067 Lying all across the bay... 590 00:43:08,169 --> 00:43:11,671 Piles of junk, hundreds of yards long. 591 00:43:11,773 --> 00:43:17,310 Shipwrecks, bricks, and wood pilings. 592 00:43:19,514 --> 00:43:22,515 James: If you were to drain mobile bay you would see still 593 00:43:22,584 --> 00:43:26,102 To this day, a number of obstructions, that were placed 594 00:43:26,204 --> 00:43:29,939 There by the confederates to keep the union navy out. 595 00:43:31,443 --> 00:43:33,943 Narrator: None of these could cause the severe damage 596 00:43:34,045 --> 00:43:36,779 Discovered on the tecumseh. 597 00:43:36,881 --> 00:43:40,300 But that's not all that the confederates place here. 598 00:43:42,137 --> 00:43:44,570 They also deploy these... 599 00:43:44,673 --> 00:43:48,141 A terrifying new weapon; known today as a sea-mine, 600 00:43:48,877 --> 00:43:52,478 But back then, also called a torpedo. 601 00:43:53,815 --> 00:43:58,050 A torpedo unlike the one carried by the hunley submarine. 602 00:43:58,136 --> 00:44:02,372 Instead held just under the surface by a weight and chain: 603 00:44:02,474 --> 00:44:04,741 Primed to detonate on contact. 604 00:44:04,843 --> 00:44:07,644 (click and explosion). 605 00:44:08,046 --> 00:44:10,747 This underwater killer is one of the confederate's 606 00:44:10,849 --> 00:44:13,299 Most successful maritime weapons, 607 00:44:13,401 --> 00:44:17,470 Sinking or damaging 43 union ships. 608 00:44:18,373 --> 00:44:22,909 And in mobile bay, there are up to 180 torpedoes... 609 00:44:23,178 --> 00:44:26,879 Laid row after row, in a dense, checkerboard pattern. 610 00:44:30,101 --> 00:44:34,637 James: By August of 1864 the confederates had built, 611 00:44:34,739 --> 00:44:38,775 Not only an obstacle course but a gauntlet, through which the 612 00:44:38,877 --> 00:44:42,845 Union navy was going to have to fight its way through. 613 00:44:43,648 --> 00:44:46,099 Narrator: With information from the drained landscape, 614 00:44:46,201 --> 00:44:48,201 And the latest historical research, 615 00:44:48,303 --> 00:44:51,237 It's clear what happens here. 616 00:44:57,545 --> 00:45:00,480 Commanding the union fleet is admiral david farragut 617 00:45:00,648 --> 00:45:03,549 On the steam and sail-powered uss hartford. 618 00:45:05,036 --> 00:45:08,171 Farragut knows he faces underwater torpedoes, 619 00:45:08,273 --> 00:45:11,074 But he doesn't know where they are. 620 00:45:12,410 --> 00:45:15,144 He sends in the ironclads first... 621 00:45:15,246 --> 00:45:18,781 Carefully, in single file. 622 00:45:18,883 --> 00:45:22,668 Leading the line, the tecumseh. 623 00:45:26,141 --> 00:45:30,109 She fires the first shot at the rebel-held fort. 624 00:45:31,079 --> 00:45:34,313 Then, as the fleet enters the bay... 625 00:45:35,150 --> 00:45:37,734 (explosion). 626 00:45:37,836 --> 00:45:40,069 Craig: Gigantic explosion, the bow wheeled up, 627 00:45:40,171 --> 00:45:42,038 Then down into the bay, 628 00:45:42,140 --> 00:45:45,374 The ship plunged downward, it's stern rising in the air, 629 00:45:45,477 --> 00:45:47,910 The bronze propeller still spinning. 630 00:45:49,314 --> 00:45:51,714 Anna: Within the space of about 30 seconds, 631 00:45:51,816 --> 00:45:54,867 The tecumseh went bow down and sank. 632 00:46:00,775 --> 00:46:04,844 James: It's a shocking moment, but for farragut history is 633 00:46:04,963 --> 00:46:07,480 Made when he reportedly says, 634 00:46:07,582 --> 00:46:11,033 "damn the torpedoes full speed ahead", 635 00:46:11,402 --> 00:46:14,871 The order was given to keep going. 636 00:46:15,106 --> 00:46:20,376 Anna: They report hearing the fuses of torpedoes clicking as 637 00:46:20,478 --> 00:46:24,013 They're moving through but none of them go off. 638 00:46:24,616 --> 00:46:30,203 Narrator: The union fleet breaks through and despite losing the tecumseh, 639 00:46:30,305 --> 00:46:33,739 Farragut's boldness is rewarded. 640 00:46:35,076 --> 00:46:38,110 Mobile bay falls. 641 00:46:40,114 --> 00:46:43,733 For the rebels, it's the beginning of the end. 642 00:46:45,336 --> 00:46:48,538 Craig: The size of the confederacy was quite literally shrinking. 643 00:46:50,375 --> 00:46:54,844 Narrator: Nine months later, peace returns to america. 644 00:46:58,616 --> 00:47:01,968 Draining the secrets of the american civil war reveals the 645 00:47:02,070 --> 00:47:05,404 Courage of those on both sides, who risked everything 646 00:47:05,507 --> 00:47:08,007 For their cause. 647 00:47:08,643 --> 00:47:11,944 And a technological revolution that transforms 648 00:47:12,046 --> 00:47:14,280 The navies of the world. 649 00:47:18,770 --> 00:47:19,969 Captioned by cotter captioning services.