DirtPirate I've been digging a bunch of these lately in Melbourne Australia, mine look to be exactly the same as yours except for the base marks. The ones on mine have: 5 dots like on a dice with an uppercase P who I've got zero idea of who or what that is BUT I know these bottles are American black glass 3 piece mould 1820 - 1860 I think I was told.
Hi guys
It's fascinating to hear about your discoveries in Melbourne, Australia! Those American black glass bottles with the 5-dot base marks and the mysterious uppercase 'P' certainly sound intriguing. The dating you've mentioned, ranging from 1820 to 1860, aligns with a significant period in glass manufacturing history.