it's appropriately called the dive alarm.
a diver
Below
The Nautilus was Fulton's submarine.
A submarine is an undersea boat, or submersible.
plunger is a fitting name for submarine because , it is under the water
this word is an adjective meaning "under the sea". submarine is the word shortened from the term "submarine boat".
another name for a submarine is submarinous. it is latin meaning "steel fish" or "under water tank"
The H. L. Hunley was the name of the Confederate submarine that was the first combat submarine to sink an enemy ship.
The Confederate submarine 'H L Hunley' was the first submarine to sink an enemy ship
Submersible.
Underseaboat.
Nautilus.