These are handblown glass soda bottles, typically from the 1800s. As you can see, the bases are round, and that's not a manufacturing limitation, but a design decision. These bottles were purposely designed to not be able to stand.
The reason is because at the time, bottles were all sealed with corks. Corks tend to dry out and shrink over time. With carbonated beverages, that's a problem; as the cork shrinks it becomes looser, and the built-up carbonation in the bottle can then cause the cork to pop right out, causing a major headache for the shipper or stockist.