The Irish Iceberg is a renaming of “Icebergs” on page 437 of The Boston Cooking-School Cook Book. I’m not sure how well lemon and mint go together…
“Leaf green” is a food coloring. In her recipe for Crême de Menthe Ice, just above in the cook book, she specifically calls for Burnett’s. Joseph Burnett was a Boston chemist who developed a line of extracts, perfumes and other toiletries, and food colorings.
Crême de Menthe was invented in 1885 by chemist Émile Giffard in Angers, France. The original liqueur was clear. A couple of years later he developed the green version.
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