The Momsen lung, a primitive WWII rebreather for escaping submarines.
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Transporting a submarine on a truck - GIF
Narco-submarine captured by U.S. Coast Guard - video and infographic
The H.L. Hunley, the first submarine to sink a warship
Submarine rescue chamber - photos
Raising WWII German submarine U534 - videos
Guppy submarine torpedo room - photo