Clear Glass Oil Lamp ~ Unidentified

This clear glass oil lamp has been in my collection long before it actually became my collection. There are no marks on it and I have no idea who the maker is, how old it is or if there is a pattern name (since it's pretty much smooth).
Like the green glass oil lamp I posted earlier, I beleive my Mom told me my Grandparents or Great Grandparents actually used this oil lamp to light their home, but cannot verify this due to the lack of documentation and mark.
I am asking that the Collectors of this site who might have any information no matter how limited or in depth please share your expertise with me in helping get this piece identified so I can document it in a history of my collection book I'm making to pass on to my child when the time comes. I thank you all in advance for any help and assistance you might be able to provide.