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Submarine

Country: America

Added: 2006

Category: Military Warfare

Duration: 24 mins

Abstract:

Speed， strength， stealth and power， the submarine is a mean machine， it takes man into a hostile world. Submarine design has been evolving for centuries. The dream of travelling underwater existed long before it became a reality. Man had fiddled around with the concept of the submarine for hundreds of years. All kinds of prototypes have been built but they all hit the same stumbling block. How to devise an effective means of propulsion?