Potassium (in older pharmaceutical nomenclature)(abbreviation)
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Use "potass" in a sentence
"Upon these ashes water is poured, which, filtrating through the hole in the bottom of the vessel, carries with it the potass contained in the ashes, and forms a very strong lye of the colour of strong beer: this lye they call sai-gee, ash-water."
"Dr. Watson also recommends a _drink_, prepared of a drachm of _chlorate of potass_ to a pint of water, and has found great improvement from the use of a pint to a pint and a half of this solution daily."
"Chlorate of potass -- Liquor calcii chloridi 62 92."