One of those sodas that sprang up in the wake of Prohibition. It was a “Liime Soda, with just a touch of Lemon” - possibly another entry in the Seven-Up / Sprite sequence of indistinguishable non-colas, but it was beloved by some. Still made, but not widely distributed.

Eddie Cantor wrote the jingle:

For a drink that's fine without a kick,
Try Green River,
It's the only soft drink you should pick,
Try Green River.