This is an antique, Glyco-Thymoline quack medicine bottle dug from an 1800s era plantation home in Virginia.  The vintage remedy bottle is embossed, "15 1/2 Fluid Oz. Glyco- Thymoline" on the front and "K - 6" on the bottom.   The vintage apothecary bottle likely dates from the late 1800s to the early 1900s.   My father, an avid bottle found the bottle more than 40 years ago.  The bottle is in nice condition, however there is an internal scar on the front of the bottle.  The scar does not go thru the glass and is on the inside only.  There is also a small chip on the lower rim.  (See photo close ups).  Embossing is sharp.  Clarity is nice although there is some calcium deposit from exposure.  The old medicine bottle measures about 9.5" tall, 3.75" wide and 2" deep.

Glyco- Thymoline was developed by Samuel Owen and Oscar Cress in 1890 New York City as a remedy for cold symptoms.  It was a popular mouth rinse and was marketed as the world's first mouthwash.  It also apparently was a feminine hygiene aid, soothed baby's skin irritations, minor burns, poison ivy and sunburn.  Amazon even sells a version of Glyco-Thymoline today.  (Thankfully, its just advertised as mouthwash.)

https://americanhistory.si.edu/collections/search/object/nmah_209672

http://dustoffthebottle.blogspot.com/2012/10/glyco-thymoline-bottle.html

https://baybottles.com/2019/05/05/glyco-thymoline-kress-owen-co/