Original subtitles

This is between the years 1775 to 1783

When the American Revolutionary War was being fought between

North America and Great Britain

Americans wanted to elect their own representatives

And run your own government

Do not run the British American government

For a long time the Americans were angry with the British policy

because the British policies were quite strict anyway

which included the collection of taxes and the use of resources

Holland, Spain and many European countries sided with America

in this war

But in the meantime, an invention occurred that

changed naval warfare for the future

He was an invention

The world's first submarine

As in those days, when a country had to be attacked,

ships were dispatched

And then this war was fought in the open sea or after the ships

were anchored in the sea, the soldiers were placed in small boats

and the army was sent to the land.

david bushnell who was a doctor by profession

But his interest was more about science and different

kinds of inventions

Like every loyal citizen, david bushnell had a heart to do

something for his country, America

During the American american revolutionary war, he decided to

create something that would cause an enemy ship to

crash into the water.

Then he invented a submarine named Turtle Submarine

From a distance, it looked like a turtle, hence the name turtle

Before starting the description, let me tell you that this

is happening between the years 1975 to 1976.

The story of the invention of this submarine is very interesting

david bushnell also had in his mind to build a watercraft that

could run underwater and carry out all military

operations from underwater.

It was the first invention of its kind at that time and no blueprint

of any kind existed in anyone's mind, before that time man had

learned to sail boats and watercraft on water and the ships of the

time were definitely the modern ones of that time. There were ships

But nothing had been invented that could move underwater and

simultaneously attack the enemy

I am not saying here that no one would have thought of the same

invention before, certainly they would have thought and tried, but

the submarine I am talking about was the first

documented submarine.

Most interestingly, it involved a watchmaker, a brasssmith

and a woodworker.

For this purpose, he built a carpenter's wooden frame made of pine wood

and shaped like an egg, 6 feet long and 3 feet wide.

A large iron plate was molded on top of it by the blacksmith

So that water cannot enter the submarine

Ballistic tanks were also installed on either side of the submarine to increase

weight by filling the hot tanks with water when the

submarine went underwater.

And when it needs to be brought back to the water, they can simply pump

the water back out with a hand pump attached to the ballistic tank.

so that the submarine can return to the surface of the water

The submarine was also equipped with propellers to drive it underwater

Which had to be operated manually

And they also had to make arrangements to drive forward or backward by means of propellers

The watchmaker also installed some instruments for navigation,

including a compass to determine direction and a water gauge to gauge the

depth of the submarine.

A small glass window on the side called an Eyelet helps

the pilot to see out.

This submarine was built for military purpose

so a papaya-shaped mine was installed in it

It was attached to a rod like a screw driver so that it could be

attached to any ship in time.

The papaya-shaped mine was also fitted with a timer so that it

could be returned by sticking a bomb on a part of the ship.

The mechanism of the submarine was also very interesting,

it had a door for entry that opened from the top and closed.

The submarine was so narrow

that the pilot could hardly get inside

It could seat only one man, meaning only the pilot could run it

And he had to do all the work himself

Certainly this submarine was operated manually

Inside the submarine was a manual crane that powered

the propellers on the outside

Due to which it was moving forward and backward

When a change of direction was required, the rear propellers

were manually held to allow the change of direction.

And it is estimated that its speed was about

four and a half kilometers per hour

And the most interesting thing was that its speed depended on

the health of the pilot

Taking the submarine under water

Bringing a submarine to the surface and escaping by attaching

explosives to the hull of any ship.

And also maintaining the balance of the submarine

And above all to ensure oxygen supply for yourself

These were all the little things the pilot had to do on his own

Its construction was completed within a year and it was then

tested at sea against a British warship

But from the military point of view, this submarine did not

achieve any significant success

This was because there were many technical flaws in it

As I mentioned earlier, if a pilot has to do all these tasks himself

during the war, even if there are no technical problems,

the problem comes somewhere.

But the Turtle submarine gave the

world a new topic for the future

This atomic submarine you see

Or an automatic unmanned submarine

Or a modern submarine like ocean gate was based on the

same submarine whose first practical was not so successful.

But the foundation of this first submarine helped create

the most reliable submarines of today

All the systems that were installed in this submarine are

still used in modern submarines with modifications

This turtle submarine of David Bushnell changed the map of

naval warfare today

It changed not only warfare but also underwater campaigns