You know how it is. It’s gin and tonic season, and you go to the grocery store and pluck a bottle of the usual tonic water from a shelf and there it is. One day, however, I was in Whole Foods, and I saw, on a bottle shelf, a four-pack of little bottles of Fever-Tree Tonic Water, so I bought a set and the next time I made gin and tonics of LL and me, I used it. Wow, what a difference! More effervescent, sharper, tangier, drier, chastely medicinal, great balance; tonic water for grown-ups. Next time I was at Whole Foods, however, the store was out of the Fever-Tree Tonic Water but had Fever-Tree Bitter Lemon. This is slightly yellower that the pale tonic water and a little cloudy from pieces of lemon pulp. It too contains quinine, the basis of tonic water, but the lemon component seems to lend more body and a citric tang that jazzes the dryness and slight bitterness without being puckery. I suppose one cannot call the cocktail of gin and bitter lemon (with a squeeze of lime juice and a slice of lime; a sprig of mint is good too) a gin and tonic, but it’s one of the most refreshing and summery cocktails around.

Fever-Tree was launched in 2004 by Charles Rolls and Tim Warrilow; Rolls ran the Plymouth Gin company. Fever-Tree, which is based in London, also makes ginger ale and ginger beer that I would dearly love to try. Fever tree was the name given to the cinchona tree from which quinine is derived. British officers in India began mixing quinine with water and sugar in the 1820s to ward off malaria, and it must work, because I’ve consumed about a billion gin-and-tonics in my lifetime and I’ve never had malaria. Fever-Tree products contain no preservatives, artificial sweeteners or coloring agents.

A four-pack of 6.8 fluid-ounce bottles is $4.99 at Whole Foods.