What does "microcosmic" mean?

Microcosmic: Of or pertaining to the microcosm. Microcosmic salt (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.

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