The submarine which can travel unseen, under the water surface, is not something new invented during the World Wars in the 20th century. It was known at least 200 years before The World war I.

The theory of under-water-travel had been known to the ancient Greeks. Archimedes and Aristotle had mentioned the attempts made in making diving bells.

In 1620, a Dutchman Cornelius van Drebble built a wooden boat and covered it with greased leather to make it water-tight. He successfully rowed it 15 feet under the surface of the River Thames.

In 1776, David Bushnell, an American, built “Turtle”, the first submarine to be used as a weapon of war. In 1800, Robert Fulton produced “Nautilus”. He hoped to sell it to the French to be used in their war against England. But France was neither impressed nor interested!

Most of these early crafts had very limited under water range. They would run out of steam or air or both! With the help of reliable electric motors, this problem was solved in the 1880s.