Painted font oil lamp

I picked this up today because I thought it was a good deal but I don't really know what I have. The glass looks hand made and certainly hand painted. I am guessing 1800's but it may be later. If anyone has some info I would love to hear it. There are no markings that I have been able to find, either on the glass, the base or the burner. The chimney is a simple glass one that is slightly oblong instead of perfectly round.