Based on the photo which shows on the auction's main page, my first impression (before I read the seller's Description) was like Pipedreamer65's, and other people the seller mentions, that it is a road construction warning "smudge pot" kerosene torch. But as the seller mentions in the Description info, the ball-shaped construction warning torches have a flat-spot on the bottom, to prevent rolling. The seller's other photos show this object has no flat-spot.
I do not know what that Ebay object is, but I am 100%-certain that it is not an artillery projectile. This ball's walls are much too thin to withstand the cannon's firing-blast -- which would immediately fracturing such thin walls.
Nor is it a grenade. I can understand the seller's logic, based on the object's somewhat-similarity to an Excelsior grenade. But the two halves of the Excelsior grenade's body screwed together, via fine threading around the rim. They weren't glued or welded together, like the Ebay ball was.
Furthermore, the INTERNAL "ball" inside the Ebay object is clearly out-of-round (somewhat egg-shaped). The Excelsior grenade's internal ball was perfectly spherical, as shown by the Ebay seller's photo of an Excelsior grenade's components.
The seller's use of a ruler in various photos is inconsistent. But based on several photos with the ruler, the larger ball appears to be between 4 and 4.5 inches in diameter. That is larger than any grenade. (The Excelsior grenade is 3.37 inches in diameter.)
There are other issues about the Ebay ball, like the small IRREGULAR hole in one of its halves, but I think I've pointed out enough to conclude that it is not a Military object.
Regards,
Pete
