Crisply cooling and refreshing with the added “medicinal” benefit of the quinine in tonic, this most patrician of drinks evokes the most patrician of Island towns: Edgartown. In summer. On a dock. Under a flag. Wearing pink.

For most purists, the tonic is Schweppes in acknowledgement of the drink’s origin in nineteenth-century India when the quinine was used as an antimalarial. While novices concentrate on the gin and tend to ignore the mixer, tonic from a soda gun is anathema to any cocktail maven; it must be poured to taste from a bottle or (Lord forbid) can. Some are even trying new gourmet tonic waters such as Stirrings, which can claim a Nantucket origin. Its crisp taste is a lemony surprise.

The gin will vary among the usual suspects, including Tanqueray, Gordon’s, Bombay Sapphire, and Hendrick’s. However, small batch-made gins prepared from locally grown botanicals increasingly offer aromatic alternatives. Try to get your hands on the citrus-inflected dry Junipero from San Francisco; Perry’s Tot Strength Navy Gin, an overproof from New York; or Aviation Gin from Portland, Oregon, with hints of lavender and cardamom.

Garnish is usually a slice of lime, but there are partisans of lemon wedges, and Hendrick’s suggests a cucumber spear. Inspector Crabbe of the BBC series Pie in the Sky was a no ice/no slice man, but that seems extreme.The recipe is simple and the proportions vary to taste, from one part gin to one part tonic, to two parts gin to three parts tonic. The trick is to mix it to the taste of the drinker.