(NEXSTAR) — Have you ever been strolling along a Texas beach — or a beach anywhere — and stumbled upon a bottle? Of course, you’ve probably encountered empty ones. But have you ever found one with an assortment of plants, hair and other items?

That would be what’s known as a “witch bottle.”

The Harte Research Institute for Gulf of Mexico Studies at Texas A&M University Corpus Christi says it recently recovered one such bottle on the Gulf shores. “Witch bottle!” wrote the institute in a Facebook post last week. “We find these every once in a while.”

But just what are witch bottles? And why do they wash up on Texas beaches?

The concept of a witch bottle goes back centuries — and yes, they have been historically associated with the supernatural and magic, as explained by JSTOR Daily writer Allison C. Meier. But don’t let the name fool you, witch bottles weren’t used by witches, they were used as a way of stopping a witch’s malevolent spell.

Interestingly, witch bottles were viewed as a kind of medical treatment or healing rather than shadowy objects. Dr. Annie Thwaite, a research project coordinator at the University of Cambridge, explains in a 2020 edition of the academic journal Magic, Ritual and Witchcraft that this remedy goes back all the way to the 17th Century and have a complex history.

According to Thwaite, the bottles would be filled with urine or hair of the person who was believed to have been cursed. Additional items could be added to the bottle for effect, including nails and pins. Next, people would boil and/or bury the item inside or under their homes. Anthropologist Christopher C. Fennell explained in a 2000 study that bottles were sometimes put in chimneys or hearths, since it was believed witches infiltrated homes that way.

The concoction was believed to cause the witch who cast the spell so much pain that she would either relent and undo it or else die, effectively breaking the curse.

Over time, Thwaite explains, the term “witch bottle” and its concept came to be seen as witchcraft itself, when at the time, the practice was not seen that way — at least not strictly.

She writes: “… we should not only recognize the [bottles] as a facet of ritual, magic and witchcraft, but also as a facet of healing; and not as a preventative measure, but as a cure for a specific case of bewitchment.”

Back in 2020, a Civil War-era witch bottle was found underground during an archeological dig in York County, Virginia. William & Mary Center for Archaeological Research told Nexstar’s WRIC in Richmond that researchers were able to verify the item’s dating back to the 1840s by the raised lettering on the bottle, which corresponded with what one cola company had released at the time.

Here on the Texas coast, Harte Research Institute Director of Community Engagement Jace Tunnell says he’s found at least eight in his time scouring beaches. Tunnell told McClatchy News he has several unopened bottles in his backyard.

It’s important to remember witch bottles have been found all across the U.S. — since witchcraft scares were common in the past — so Texas isn’t alone in bottle finds. Tunnell told McClatchy it’s unclear where the bottles originated, though they likely came from the Caribbean or South American regions. This could account for proximity of the finds on Texas beaches.