in seine

Recipe A:
1 1/2 oz Cognac (Martell)
3/4 oz St. Germain Elderflower Liqueur
1/8 oz Absinthe (Pernod)
Stir with ice and strain into a cocktail glass. This is the recipe I was given at the event.

Recipe B:
1 oz Cognac (Couvoisier)
1 oz Bourbon (Buffalo Trace)
1 oz St. Germain Elderflower Liqueur
1/8 oz Absinthe (La Fée Parisienne)
1/2 Egg White
Shake with ice and fine strain into a cocktail glass. Garnish with a 3 grapes on a stick or a rubber ear. This is the recipe in the Tales of the Cocktail Recipe Book. I do not remember this as an egg drink, and the book states that it was the recipe for a different event.
On Friday afternoon at Tales of the Cocktail, we went to the Pernod tasting room which seemed rather focused on the re-release of their absinthe. One of the drinks I had, the In Seine, played on the past fears about absinthe coupled and its popularity in Paris (on the Seine River) with its name. The drink itself was very St. Germain tasting with just enough absinthe on the swallow to add a lot of complexity. Unlike some drinks, the absinthe flavors were not overwhelming. And after having the Monkey Gland in the same room, I believe that the bartenders in this tasting room might have been going a lot lighter on the absinthe to appeal to a broader audience.

The Tales Book (recipe B) was created by Simon Difford at the Cabinet Room in London, and the drink presented at the Pernod tasting room might be a variation on it. The Difford recipe was served at the "Hammer of the Gods" event. The book also states that "The name references the fact that St-Germain is a district of Paris on the left bank of the River Seine and absinthe was banned in Paris, partly because it was believe to induce insanity." My best guess is that the drink we had at the tasting room was closer to recipe A, but recipe B is most likely the original.