h can go miles under the water without once coming
to the top.

We call these submarine boats, and look upon them as something very new.
You may be surprised to learn that there was a submarine boat as long
ago as the War of the Revolution. It was not a very good one, and did
not do the work it was built for, but it was the first of its kind, and
that is something worth knowing.

Those of you who have studied history will know that after the British
were driven out of Boston they came to New York with a large army, and
took possession of that city. Washington and his men could not keep them
out, and had to leave. There the British lay, with their army in the
city and their fleet in the bay and river, and there they stayed for
years.

There was an American who did not like to see British vessels floating
in American waters. He knew he could not drive them away, but he thought
he might give them some trouble. This was a Connecticut man named David
Bushnell, a chap as sharp as a steeltrap, and one of the first American
inventors.

What Bushnell did was to invent a boat that would move under water and
might be made to blow up an enemy's ship. As it was the first of this
kind ever made, I am sure you will wish to know what it was like and how
it was worked.

He called it _The American Turtle_, for it looked much like a great
swimming turtle, big enough to hold a man and also to carry a torpedo
loaded with 150 pounds of gunpowder. This was to be fastened to the
wooden bottom of a ship and then fired off. It was expected to blow a
great hole in the bottom and sink the vessel.

Of course, the boat was air-tight and water-tight, but it had a supply
of fresh air that would last half an hour for one man. There was an oar
for rowing and a rudder for steering. A valve in the bottom let in the
water when the one-man crew wanted to sink his turtle-like boat, and
there were two pumps to force the water out again when he wanted to
rise.

There were windows in the top shell of the turtle, air pipes to let out
the foul air and take in fresh air, small doors that could be opened
when at the surface, and heavy lead ballast to keep the turtle level. In
fact, the affair was, for the time, very ingenious and complete.

A very important part of it was the torpedo, with its 150 pounds of
powder. This was carried outside, above the rudder. It was so made that
when the boat came under a vessel the man inside could fasten it with a
screw