microcosmic : Idioms & Phrases


Microcosmic salt

  • noun a white salt present in urine and used to test for metal oxides
WordNet
  • (Chem.), a white crystalline substance obtained by mixing solutions of sodium phosphate and ammonium phosphate, and also called hydric-sodic-ammonic-phosphate. It is a powerful flux, and is used as a substitute for borax as a blowpipe reagent in testing for the metallic oxides. Originally obtained by the alchemists from human urine, and called sal microcosmicum.
Webster 1913