This is a vintage, antique Tivoli Beer Bottle from the Robert Portner Brewing Company of Alexandria VA.  The Pre-Prohibition, embossed beer bottle is mold formed with an applied crown top.  It's embossed on the front with Trivoli and Trademark in a diamond shape along with the brewery name and city. The bottom is also embossed but the letters or numbers are illegible, blurred and misshapen.  According to the references below, this particular logo was used between 1862 and 1916.  Porter, a resident of Alexandria VA, sold his beer to Union Troops quartered in northern Virginia during the Civil war.  The earliest versions of Porter bottles were blob top.  As this bottle has a crown top with mold marks stopping at shoulder, very thick glass, and a rounded heel, I would further narrow the date to the later 1800s.  The Victorian Era is probably a good estimate.  My father, an avid bottle digger, found the bottle in the ruins of an old homestead in southern Virginia more than 40 years ago.  There are some condition issues with there being a large crack, or slice on the lower portion of the bottle (the slice does not go through the bottle as it still holds water.)  There are age related gas bubbles and the glass is thick and unevenly poured on the bottom. Clarity is nice for such an old, dug bottle.    I rarely list bottles with large cracks, but the rarity of this one makes it an exception: its a survivor. (See Photos.) The vintage Alexandria bottle measures about 9.5" x 2.75"