Submarines have been in use for centuries, but it wasn’t until the late 1800s that they were commonly used in the military. Today submarines are invaluable weapons in most navies. Through interviews with engineers and soldiers, readers learn how they work and what it''s like to live and work underwater.

Submarines have been in use for centuries, but it wasn’t until the late 1800s that they were commonly used in the military. Today submarines are invaluable weapons in most navies. Through interviews with engineers and soldiers, readers learn how they work and what it''s like to live and work underwater.