How much is a “glass,” in an old English cocktail recipe (1930)?

Question

Cocktail recipes in a reprint recipe book frequently call for liquors by the measure of a “glass.” Just how large was this?

Answer 1

I am not sure if "glass" in your recipe is the same as this, but in David Wondrich's book, "IMBIBE!" (about vintage cocktail recipes), he indicates that a "wineglass" measurement in vintage recipes was equal to 2 ounces.