I have what I believe to be a Federal Parrott shell. It has been in my family for generations, collected by my great grand father. This shell has weathered perhaps 30 to 35 yrs out of doors as an ornament on a fence. In later years my father, now deceased (an ordnance officer-Aberdeen Proving Grounds) had little knowledge of its disposition. Yet, we never ran for cover when happening across this projectile. I can peer into the top of the projectile approx. 1" into what looks like the cement that great grandpa added to this shell. Please offer me some advice on the object in my possession. It would be greatly appreciated.