Received the following question in a comment:
“I’m curious about the ‘evidence’ for Hercules being a wine-and-herbal yerba-mate drink. Some years ago I thought I found ‘evidence’ that it was a very strong Welsh beer, ie: there was a brand with that name. Since then I have concluded that Hercules was a British version of absinthe, or possibly Czech absinthe bottled here. Vantogrio was certainly Czech. My guess is that it was a non-alcoholic anise-flavoured syrup. But Hercules just has to be strong…”
While there have undoubtedly been numerous products named Hercules over the years, I believe the evidence is fairly conclusive that the “Hercules” called for in Savoy Cocktails was neither an Absinthe Substitute nor a strong Belgian Beer.
Please refer to the topic on eGullet for the full rundown of the timeline of events and theories.
Here are some of the ads which friends have turned up and scanned from various London publications, contemporaneous with the publication of the Savoy Cocktail Book.
From the Times, 1927:
From vol. 74 of the Strand Magazine, Jul-Dec. 1927:
From Harry’s ABC of Mixing Cocktails, ca. 1928:
From the Times, dated April 21, 1928:
Underhill Forbidden Fruit Liqueur
Peel from 1 Marsh Ruby Grapefruit
Peel from 1 Cocktail Grapefruit*
Peel from 4 small Blood Oranges (golf ball size)
1 Tablespoon Cardamom Pods, crushed
1 Tablespoon Coriander Seeds, crushed
3/4 bottle Vodka
1/2 bottle Brandy
1/2 pound Orange Flower Honey
1/2 teaspoon natural vanilla extract
Steep peels with spices in vodka and brandy for 2 weeks. Strain out solids and add 1/2 pound Orange Flower Honey and 1/2 teaspoon vanilla extract. Shake to combine. Let stand another week and rack off clear liquid from settled solids. Makes about 750ml.
As the Pomelo and honey based Forbidden Fruit is a truly lost ingredient, I have no choice but to attempt to make it myself. Fortunately, there’s only about 1 cocktail in the whole world which calls for it. Unfortunately, that cocktail starts with “T”, so I needed to get busy and make some Forbidden Fruit analog tout de suite.
I missed Pomelo season by a week or two, so am using blood oranges and a couple kinds of Grapefruit. I forgot to buy a vanilla pod, so used natural vanilla extract instead.
As a first (second, actually) try this isn’t bad, the sweetness about on par with Cointreau. I think in the future, I would leave out the ginger. It was a last minute impulse add. Initially it was all heat, but as the heat fades, it evolves into a menthol/camphor flavor which I am currently considering a flaw. A tad bitter, I may have over steeped the peels, or gotten too much pith when I peeled. It will be interesting to see how it evolves, as most orange liqueurs are aged significantly before being bottled.
*”Cocktail Grapefruit are exceptionally sweet and juicy. They are not actually a true grapefruit, but a cross between a Frua Mandarin and a Pummelo. This variety has a similar flavor to a grapefruit but is sweeter and less acidic. Cocktail Grapefruits are grown in the Central Valley of California and they are hand picked for the best quality.”