I found an old bottle on my shoreline today. It about 6" tall and has mold seams on the sides and at the bottom edge (cup base mold?). The neck of the bottle is ridged and at the top looks like it was a screw top. Everything I have looked up for the mark on the bottom says that Armstrong was an A with a circle, but this has the circle A and then the letters spelling out Armstrong. Underneath Armstrong it says 3.7. Any thoughts on the dating of this bottle or what it was used for? Thanks!