Реферат на тему Submarines Essay Research Paper Military submarines were
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Submarines Essay, Research Paper
Military submarines were invented by David Bushnell. He was born in Saybrook Connecticut in 1742, and died in 1824. He built the first military submarine in 1775.
The name of this submarine was, ?Bushnell?s Turtle.? The reason for this is because it looked like two turtle shells fused together to form an egg-like case. Lead ballast kept the craft upright and it was propelled by hand-operated screw-like devices. The submarine was submerged when a valve admitted sea-water into a ballast tank, and rose when the tank was emptied by a hand pump. The armament of the ship included a single gunpowder bomb with a time-fuse. One of the key setbacks to this innovation to warfare was it?s lack of an onboard oxygen supply. Lacking this, ?Bushnell?s Turtle? could only remain submerged for a half hour.
The reason that this type of machine was developed was because Americans were looking for a way to ambush English ships.
Unfortunately though, Bushnell?s Turtle was a failure in it?s own right. Even though , it?s concept to sneak behind enemy lines undetected and wreak havoc was formidable.
Submarines have come a long way since Bushnell?s Turtle with it?s hand powered controls, to it?s lack of an onboard oxygen supply. Today, most military submarines are nuclear powered. Therefore, they are able to remain at sea for extended periods of time without having to return to port to refuel. The reactors in most submarines are designed to provide propulsion for at least four-hundred, thousand (400,000) miles without refueling. Try to imagine what your life would be like without the submarine. Without it, we may be living under German rule, or everyone in the world would be at war. Consider yourself lucky that William Bushnell had the perseverance to invent the military submarine. It has truly changed everyone?s life.