Fancy tonic waters abound. Do you need one to make a good gin and tonic?
What We Learned
As its name implies, tonic water was originally used as a curative. In 19th-century India, where malaria was rampant, quinine, an alkaloid extracted from the bark of the cinchona tree, was the primary means for both preventing and treating the disease. Like all alkaloids, quinine is intensely bitter, so British colonists diluted it with carbonated water, forming a tonic. Later, they...