What are some interesting facts about Merrimack v. Monitor?
First, if you wish to be technical, it should be the battle between the C.S.S. Virginia, which is what the Confederacy named the captured Merrimack after it was recovered from being scuttled at Norfolk Naval Yard. The Monitor actually describes a class of riverine and coastal ships--monitors would be used in the naval warfare on rivers in the Confederacy throughout the war.
It was rumored that the Virginia would steam its way past Hampton Roads, open up the federal blockade, and even shell Washington D.C. This one ship started an evacuation of the Federal capital and even Mary Todd Lincoln and her children felt compelled to leave the city--all because of the presence of this one ship! Given the damage she inflicted on three wooden ships, people felt that their fears were justified. The Virginia's key weapon was a ram in the bow of the ship, which was meant to literally knock holes in enemy ships. This was a common way of waging war in an era of smooth-bore cannon.
This would be the first battle between ironclads in history--ironclads saw very limited action in the Crimean War, but never faced each other. The Virginia used the time-honored method of firing broadsides into its quarry, while the Monitor used a revolving turret gun--this revolving turret would be the model that other navies would model thereafter. No one actually died during the battle, and both sides claimed victory. The Monitor sank in a storm (it had such a shallow draft that it was not meant for open ocean travel) and the Virginia was destroyed rather than fall into Union hands before the end of 1862.