Lommebogen calls this a "cobbler," which it really isn't, but close enough. This is the classic summer drink, and it's perfect to have during a Copenhagen heat wave. Basically you have a gin lemonade, and it's lovely. There are all kinds of stories about how it got its name, and I'll let the Wall Street Journal provide some history for you. You can also find many variations on the Tom Collins, with other names that represent swapping out the main spirit, like John Collins is whiskey, and Juan Collins is tequila.
This one is a whole bunch of liquor. Instead of just a shot of one spirit, it's simply a blend of 3 shots, with the absinthe added as an afterthought to make it a "cocktail." Lommebogen and Café Royal have the same recipe, but Savoy has two different recipes for this one. The one that matches the other two books is actually Savoy's #2 version. The Savoy #1 is quite a departure, and seem much more approachable. Another place to use a little crème de menthe.
Another interesting vermouth cocktail, with two very different recipes here. Aside from the different spirits used, the emphasis, or lack thereof, is pretty marked between the two. The combo of apple brandy and gin doesn't sound terribly appealing to me on paper, so I'm curious how that one will come out. The modern recipe uses apple brandy and vermouth, with some dashes of bitters and simple syrup, which sounds like a better combination than the gin.
The Singapore Sling is one of those classic drinks where the recipe ends up all over the place. There is a lot of murkiness around the original recipe, and the variants since then. I'll leave it to others, like David Wondrich, to walk through the history of it all. The main differences we have in our three books lie with the Savoy not using Benedictine, and the different proportions.
I love fizzes. The most famous fizz, the Ramos Gin Fizz, was one of the first cocktails I completely fell in love with. This recipe is very similar to the Golden Fizz, except we are using the egg white instead of the egg yolk. Makes sense, right? Lommebogen also adds a tiny bit of cream to this as well, which isn't an uncommon thing (the Ramos Gin Fizz uses egg whites and cream). I'm curious to see if that has any real effect on the color or texture of the drink, especially since there is so little of it.
Another of the classics that is still widely made today, this time from the sour family. All three books have a slightly different take on the same basic premise: sour, sweet, and cognac. I love me some sours (and enjoy a good Sidecar), so this is right up my alley. Lommebogen shakes things up with some Angostura (and extra sweetness with sweet and sour versus straight lemon juice). The Savoy plays with a different ratio, giving more weight to the cognac.
The odd thing about this "cocktail" is that it is basically a seasoned raw egg, or egg yolk, served in a glass. This isn't about spirits. I can see where the name Prairie Oyster came from, in that you have a small, round, raw item that is accompanied by toppings you might easily find with oysters from the sea (and these have no relation to the *other* prairie oysters I'm familiar with). The Hen name makes sense as well since you are using an egg here.
Anything with "pink" in the name is bound to have grenadine in it. All of the books have gin and grenadine for this, but Lommebogen gives a wallop of sweet with a healthy dose of curaçao, and then tries to balance that with a little lemon juice. The Savoy/Café Royal version sticks to grenadine for the sweetener and adds an egg white.
Paradise. Mmmm. I'm thinking beaches and palm trees, and someone bringing me cold drinks on the beach. I don't immediately place gin there, but I could be convinced. This looks like a pretty sweet cocktail on the tin, but this is the same in all three books. That dash of lemon juice doesn't look like it's going to balance very much of the sugar.