“Never before was anything like it dreamed of”
A work-in-progress. I’d forgotten what a subtly complex shape Virginia‘s sloped casemate really was. Flat, orthagonal drawings don’t do it justice; there’s not a straight edge in the entire thing. That, and how big the ship actually was. Little wonder they thought it was nigh-on invincible.
Dead Confederates, A Civil War Era Blog 
It does have a strange, stealth appearance, almost as if someone was worried about its radar signature. What the Monitor had, however, was that revovling turret which let it turn on a dime and continue firing at the Virginia as it went in another direction.
See this Union version of the Hunley? Apparently it was tied up in court. Also very modern.
http://en.wikipedia.org/wiki/Intelligent_Whale
As I understand, Virginia‘s iron armor plate was four inches think, forged in eight-inch-wide strips. (This was on top of a couple of feet of timber.) How they managed to bend and fit those to the compound curves of the ship’s casemate, I have no idea — difficult enough with simple half-inch plating. Little wonder that every other Confederate ironclad was built with flat plating.
Correction — the four inches of iron was in two, 2-inch thicknesses, bolted one atop the other at right angles. Still not easy to shape, but much more workable than a four-inch thickness. I should’a remembered that. My bad.