If these are the small, narrow glass tubes about 5 cm long, sealed at both ends and containing liquid, they are most likely some type of glass ampoule or vial. Their exact purpose cannot be confirmed from the description alone.
If you can upload a clear photo, especially one showing the ends, any markings, the liquid’s color, and where they were found, I can narrow it down much more accurately.
Most likely possibilities
- Old perfume or fragrance ampoules
Small sealed glass containers were historically used for perfume samples and concentrated fragrances. A bathroom cabinet would be a plausible place for an old personal-care product to have been forgotten. (RR Blog) - Pharmaceutical ampoules
Sealed glass ampoules have long been used to store sterile medicines and chemical solutions. Some are deliberately made as narrow tubes with sealed ends. (Chest of Books) - Cosmetic or hair-treatment samples
Older beauty products were sometimes packaged in tiny glass containers, particularly concentrated treatments and samples. - A chemical or laboratory product
This is less likely simply because they were found under a bathroom cabinet, but it cannot be ruled out without seeing the tubes.
⚠️ Don’t open them yet
Because the liquid is unidentified and the tubes may be old, don’t break, cut, sniff, or taste them. Even apparently ordinary ampoules can contain pharmaceutical or chemical substances, and breaking sealed glass creates a separate injury risk.
The shape of the ends is especially useful for identification. If you upload a photo, I can look at whether they’re true ampoules, perfume vials, moisture indicators, or something else.