Are there any hints on who made it, or how it was made? Is the tube made of Iron / steel? You don't want to do anything other than display an aluminum tube! Does the bore look like it's of consistent caliber all the way down? That would indicate it was a drilled bore diameter rather than cast over a clay plug. These days, many cannons are cast iron (or steel) over a DOM (drawn over mandrel) steel liner, but some, like Steen Cannons starts out with a big steel blank, and then machines it down.
If there are hints in the dating that would be good to know too. In the olden days, cannons were molded with the muzzle down over a clay plug. The impurities would be lighter than the iron, and float to the breech end, or in to the cascabel and got cut off as scrap, or otherwise known as dead heads. If the foundry's metallurgical quality control wasn't that great, then some times the impurities were in the actual breech area, and a failure there doesn't just hurt one person, it killed the whole gun crew.
So be careful with it. Odds are you'll be fine, but I would still proceed in firing it with caution. A metal x-ray wouldn't be entirely out of order either before firing, especially with full power projectile loads.
Looks really cool though. Great find. In the looks of how it was displayed as found (in a second hand store) you probably got it pretty cheap.
