The ship-board gun system your referring to is called the "Phalanx." A land-based system used to protect against rockets, mortars, and artillery is caller the "Centurion." Both gun systems are based around the Vulcan cannon.
I served as a senior gunner on a self-propelled M163 Vulcan Aid Defense System (VAD) in the early 70's. They also had a towed version.
It's why I wear hearing aids these days.
Again, Dr. Gatling would have no trouble recognizing his invention.