Gatorboy. I am an avid detectorist and starting to get a fever for this bottle thing. The black bases on the broken pcs look familiar to me. I found an exact black base shard like the ones you posted. There was some pipeline construction taking place and an area was clear cut and all debris was removed. The soil was a little sandy and after a rain i found a pc like yours and on the bottom i saw the letters "BRI". I carried it around for a few minutes because i had never seen a glass shard quite like it. I dropped it on the ground later. Now i kind of regret leaving it there. I am planning to do some privy digging there and who knows, maybe i can find a whole pc
Good luck with that. That sounds like a good place to detect. You might find some things like this.
Since glass is fairly light for it's size and often has a lot of surface area it will often wind up on the surface and be a great indicator for more dense items below the surface.
Thanks for the info. I remember this plave like it was yesterday because another detectorist walked away from the site with a small cast iron pot containing who knows what. He beat me there by about an hour. He was so excited he didn't cover the hole back. In the bottom of the hole was a perfect indentation of a 3 legged cast iron pot. ... I remember hunting around a depression in the ground that i assumed was the well for the homeplace. Who knows, could have been a privy. It was about 8-10 inches lower than the surrounding area 'and probably 3 ft in circumference. It is now a briarpatch but i think i will do some "probing"