text: The figurative usage of the expression gained popularity during and after the California Gold Rush, but had currency even before then. An example from the Wisconsin paper The Columbia Reporter, November 1845, illustrates this: "Twenty-four years of service demonstrates his ability to stand the acid test, as Gibson’s Soap Polish has done for over thirty years."
  Other instances of the figurative use of the phrase include websites like Acid1, Acid2, and Acid3, designed to test web browsers for compliance with current web standards. Financial analysts also employ the "acid test" nickname for the quick ratio method, which assesses the liquidity of a business.
  The term "acid test" took on a different meaning in the realm of experiences with the psychedelic drug LSD, popularized by the Merry Pranksters. This association stems from the drug's colloquial  name, "acid" (which chemically it indeed was).