New Orleans had a sewer system by that time and they were outlawed. In smaller cities they were used by a few fairly recently. I'm sure, to just make another one. I have found as many as six in one back yard in New Orleans, from the turn of the century back to the 1820's. They may seem to be practically solid glass, nearly empty, filled with unusual articles, or any combination of the above.
H unting for old bottles is like being a prospector.
Every time we go out the big strike might be made. I live in Houma, some 50 miles from New Orleans. We worked from daylight to flash light, and once I even talked some one into letting us plug in a drop light through a window to finish a dig. We also crawled under 18th century houses looking. New Orleans is mostly at or below sea level.