It isn’t just about the gin. It isn’t all about the vodka. A first-class mixed drink is about the mixer, too. That’s why they call it a mixed drink.

At a very civilized bar in the UK, a server asked me which tonic I wanted with my sublime Plymouth Gin. Hmm. You mean there’s a choice?

Indeed. And on both sides of the pond, my choice is Fever-Tree, a premium line of all natural mixers. Ginger from Nigeria, the Ivory Coast and India. Expect the purest quality quinine from the Congo, which will keep your head cool and your palate pleased. Flavors are crisp, happy and straightforward, dear chap. No artificial aftertaste. No phony colors.

Fever-Tree is so impressive you just might start ordering a tonic and gin instead of a gin a tonic.

The brand was developed by Charles Rolls, former managing director of Plymouth Gin, and Tim Warrillow, who was steeped in premium teas and coffees before entering the beverage market.

In addition to Fever-Tree’s flagship Indian Tonic Water, there are six other labels: Naturally Light Tonic Water (only 40 calories!), Bitter Lemon, Club Soda, Ginger Ale, Ginger Beer and, the latest, Mediterranean Tonic Water, a floral mixer designed to play nice with vodka.

And now you need not head to your favorite upscale waterhole to indulge. You can buy Fever-Tree through Amazon and other outlets for your enjoyment at home. Suggested retail price: $5.99 for a four-pack of 200ml bottles; 500 ml bottles for $2.99.