Number of words – 309

The alchemist called some shiny minerals by the name vitriol, from the Lateen word for glass. There were blue vitriol and green vitriol. In smelting minerals to obtain metals, artisans got copper out of blue vitriol and iron out of green vitriol.

Later, alchemists found that if they strongly heated powdered vitriol and condensed the vapour, they’d get a liquid that would sting the skin.  They called it spirit of vitriol. They also identified it as an acid (from the Latin word for “sharp”. And that’s how the word “vitriolic” came to mean sharp and biting. The alchemists also made an acid when they burned sulphur and dissolved the resulting vapour in water. They called that, the spirit of sulphur. Only after 1600 did Europeans realize that spirit of sulphur and spirit of vitriol were the same thing. We call it sulphuric acid. But as long as the two things were obtained by different processes, it was quite reasonable to call them by different names.

Sometimes the Muslim alchemists derived the names for substances from the process by which they were obtained, and sometimes from their appearance. Alkalis refer to a whole class of materials that were first used to make soap. They were obtained from the ashes of burnt plant materials. The word actually comes from the Arabic word for frying, because they were obtained at first by frying plant materials. Sprinkling cold water on the ashes dissolved the alkalis out of the ashes. The element that comes from wood ashes is potash. The product that comes from the ashes of seaweed is washing soda. Soda is another Arabic word, which means splitting. The name soda was given to the alkali obtained from seaweed, because it was used to cure splitting headache. No kidding!

Excerpted from ‘Children of Promotheus: A history of Science and Technology’ by James McLachlan