Tonic is in the same class of ingredients as pesto. Both were used by sailors to solve a health problem. Pesto’s Vitamin C helped cure scurvy for the Genoese. Tonic stopped malaria for the British. Its key ingredient—quinine—had been known to ward off the disease since the Incas. Leave it to the British, though, to figure out how to fix malaria with a wonderful drink mixer.
I was used to a bitter, astringent tonic, and Fever Tree is much more delicate than anything I've ever had. Devised by two Englishmen who wanted a little more flavor from their tonic, it uses cane sugar, not high-fructose corn syrup. It also has herbal botanicals and natural quinine, not the synthetic stuff we figured out how to make during World War II. It’s very refreshing, featuring light, clear as a bell flavors but not too much sweetness.
Best paired with a delicate gin so as not to drown its charms. Bombay Sapphire is a smart choice.