From looking at the pictures I can't tell what it is, whether is concentric or eccentric. Its one or the other. Either way its a very neat old piece and it sure is worth the money you gave. I like these kinds of things being posted instead of a three dollar piece of junk with a request how to turn it into three hundred dollars so it can be sold on ebay or somebody that don't know better on facebook.
And I'd like to know if the piece sticking down is right in the middle or off to the side. Like I said, I can't tell from the pictures. :-/
Its a concentric kettle if its right in the middle and an eccentric kettle if its off to the side. I had a number nine eccentric kettle at the WAGS convention in Canton, Ohio. Its a beast and holds 26 quarts. I wonder what size this one is? :-/