Proportions by weight are 75% potassium nitrate (known as saltpeter or saltpetre), 15% softwood charcoal, and 10% sulfur.
en.wikipedia.org Heating turns the saltpetre into potassium oxide or hydroxide, which absorbs carbon dioxide from the air.
en.wikipedia.org The chef also mentions that once, he accidentally refilled the salt can with saltpetre, before realising his mistake and replacing the saltpetre with the real salt.
en.wikipedia.org The reaction was between melted saltpetre and acetic acid, producing a red vapor.
en.wikipedia.org The company rose to account for half of the world's trade, particularly trade in basic commodities that included cotton, silk, indigo dye, salt, saltpetre, tea and opium.
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