Tried this tonight and this is a delicious cocktail. As per Tapan Patel's suggestion of adding a little lemon, I added only a few drops and can attest that this really brightens the drink. For those curious as to who "RIP" the author of Cocktails de Paris was, it was the nom de plume of Georges Gabriel Thenon, a singer and author of revues from the early 20th century. The book was illustrated by Paul Colin, one of France's great poster artists. (Another great cocktail from that book, is the "Cocktail de Paris": https://www.diffordsguide.com/cocktails/recipe/35044/cocktail-de-paris )