Radiumwasser Flask (ca. 1920s or 1930s)
The text on this green glass flask reads "Radiumwasser von Oberschlema." In other words, radium water from Oberschlema.
In the first half of the twentieth century, Oberschlema was the most important radium spa in Germany. That ended in the 1940s when the Soviet Union decided that the area was better used as a source of uranium than rest and relaxation.
In 1958, Oberschema merged with Niederschlema to form the town of Bad Schlema. Today, following the reunification of Germany, the radon baths are once again open for business!
I assume that this bottle, probably with water in it, was once sold as a souvenir at one of the area's spas. Why the Erlenmeyer flask shape shape, I don't know. But it does give the flask something of a "scientific" look.
Size: 5" diameter at base and 8" tall