Early black glass demijohn that is actually a deep pleasing shade of green.  Much heavier than I would have thought.  The glass is so thick it barely passes light.  Sticky ball pontil.  Ca 1800.  Possibly American.  Porter shaped.  13 inches tall.  

Nice condition.  One burst bubble on the side and some wear.  Nothing too distracting.  There is a neat crude fold in the glass.  Great base wear.  

13 inches tall.