This is a vintage Sloan's Liniment bottle made for use with a stopper instead of a threaded cap. The bottom is marked with the logo of Illinois Glass and the number 19.
The closest I can get on age is that this logo was only used between 1915 and 1929.
This bottle has some cracks and scrapes along the bottom edge of the side with the raised printing. Otherwise it looks very good.
All of our glass bottles were collected by Clint's parents on their journeys around Montana. I have endeavored to date and describe them as accurately as possible. Most are very clean on the outside, but are not on the inside.
Please feel free to ask any questions or request additional photos!