maybe an early attempt at a seltzer bottle. A nozzle for pressurizing.
I still wouldnt rule out a lamp either.
The metal peice was certainly added after the bottle was blown. So someone drilled it which take a bit of effort.
Its hard to see well in the photos so just guessing really.
Wow, this is one of the most interesting bottle mysteries I've seen!
Better pictures of the inside of the bottle and base would be great. They all seem well past pontil age but it looks like the end of a punty rod got shoved in too far and when removal was attempted the end snapped off.
interesting theory.
A normal punty rod is pretty strong and if its a blow pipe they usually taper out at the end.
There is a good chance that a foreign object that big left in the glass would cause it to crack as it cools.
The rod in the bottle looks like an iron ferrule or fitting.
The cupped depression around it inside the bottle is odd. Almost like a conic pressure fracture?
Maybe the tool used to make the kick-up got stuck in the cooling glass.. or it could be a freak occurrence of damage after it was disposed of.. the inside pic looks like a metal object forcibly penetrated the bottom, knocking off the top of the kickup.. I'd lean more this way (dump damage) than a manufacturing defect; I doubt it would have made it's way into service that way..
Hmm, the metal ferrule idea sounds pretty good. Perhaps a ferrule slipped off the handle of one of the various tools in the factory and somehow wound up in the mold. Kinda looks like the bottle was blown "around" whatever that thing is.