The original Modern Cocktail from the Hoffman House is a 50/50 affair of scotch and sloe, with some additions dashed in.
McElhone offers this recipe, which he oddly doesn’t credit to the Hoffman House despite crediting them for the Mountain Cocktail on the same page.
This recipe is odd because it reads one-third scotch and one-half sloe gin.
It seems possible the first fraction is a typo, and the recipe should read 1/2 scotch and 1/2 sloe gin. If so, this error is reprinted across the editions and through the years without correction.
It is possible the mix of 1/2 and 1/3 is intentional. I haven’t checked every recipe in every edition, but if so, this is a rare or unique choice. When McElhone employs fractions, they usually add up to one (e.g., 1/3 + 2/3) OR they do not add up to one (e.g., 1/3 + 1/6) but contain various additions, some measured in teaspoons that are implied to make up the difference. (It’s not even clear to me whether McElhone’s fractions are meant to be fractions of the finished drink or fractions of an unnamed measuring vessel. He does have a few recipes explicitly measured in glasses, as in 1/3 glass.)
In any case, mixing fractional denominators that aren’t multiples of each other is not something he generally does, so pairing 1/2 and 1/3 is as weird as it reads. If there is some intent to go ever so slightly heavier on the sloe gin than the scotch, that would be an outlier of a nuance.
Thoughts?