I'll be the first to admit my geekiness, and my nerd like obsession for knowing loads of useless information. But it would seem I am not quite geek enough to know this.
On a castle, the top was usually framed out, so that an archer could stand behind a piece of wall, but still fire out from it, without having to remove himself too much from cover. You all know what I'm talking about. I'll attempt to illustrate:
EDIT:
Illustrating failed. They're the teeth like structures at the top of castle walls.
What's that called? There's a very specific name for it. And I don't think its an arrow loop. If memory serves- an arrow loop is a slit in a tower wall so that an archer could fire from inside.
