The Rusty Nail is a "duo" cocktail - a drink comprised of only two ingredients. Here the components are scotch and Drambuie. Drambuie is made with aged malt whisky, honey and a secret blend of herbs and spices. The name Drambuie is actually a Gaelic phrase - an dram buidheach which means the drink that satisfies. For an interesting history of this liqueur check out Drambuie on Wikipedia. The official IBA preparation of this drink is 9 parts scotch to 5 parts Drambuie and it's generally served in a 16 ounce highball glass with a twist of lemon, but frankly one of these at that size and I'd be under the table!
Now, serving this in a martini glass - without ice - technically makes this a Straight Up Nail as a Rusty Nail is generally served "over" or "on the rocks", both terms for on ice. The mnemonic device bartenders use to remember the ingredients for a Rusty Nail is "shoes dummy" but since I've never attended bartending school I can't tell you why those two words would trigger the memory of scotch and Drambuie! It's an interesting fact though, huh?
Anyway, if you want to try out a scotch based classic cocktail, the Rusty Nail is a good one if you're into trying out retro cocktails!
Cheers!
PLEASE DRINK RESPONSIBLY & DRIVE RESPONSIBLY!