Submarines are mighty and sneaky military watercraft. But did you know that they can carry an entire crew of people? Or that they can track where other boats are in the water? Learn more in this look at these impressive machines! Learn about different military vehicles in the Military Machines series--part of the Lightning Bolt Books(TM) collection. With high-energy designs, appealing photos, and lively text, Lightning Bolt Books(TM) bring nonfiction topics to life!