Hi John - unmarked and undistinguished glass is always a problem when it comes to age and provenance - you may struggle with this one, certainly as to maker - it might have originated in any one of several European countries.
On face value, the snail pattern feet would suggest c. 1880, but that's where my suggestions end, I think. I can't see from your pix whether there is a polished out pontil depression, or not.
Fingers crossed others may have something more useful to add.
