Hey Warren,
I'm not really a bottle digger. However whilst renovating a house a few years ago, and whilst digging outside, I uncovered a bottle with the "Poison" markings on right alongside a few bones.
From the markings on the bottle, I was able to identify it as from the 1930s, but the connection with the bones - if there was any - remains a mystery.
I kept the bottle as a souvenir.
Cheers