The Gatling gun's naval limitation

The Gatling gun demonstrated the attraction of mechanical volume of fire, yet scaling its mechanism to ship-killing power proved difficult. Its projectiles could sweep exposed personnel from a deck, support a boarding action, or help a ship defend itself in harbor. They could not penetrate the protected central section of an armored warship such as HMS Warrior, which could also fight from beyond useful Gatling range. Making a rotary weapon large enough to damage such a ship introduced mechanical problems that defeated the original advantage. Rapid fire mattered only when each projectile could produce meaningful damage at the ranges where the opponent could be engaged.