blue vitriol

American  

noun

Chemistry, Mineralogy.

1. a salt, copper sulfate, CuSO 4 ⋅5H 2 O, occurring naturally as large transparent, deep-blue triclinic crystals, appearing in its anhydrous state as a white powder: used chiefly as a mordant, insecticide, fungicide, and in engraving.

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blue vitriol British  

noun

1. the fully hydrated blue crystalline form of copper sulphate

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blue vitriol Scientific  

1. A blue, crystalline compound of copper sulfate. Blue vitriol is soluble in water, and is a very important industrial salt of copper. It is used in insecticides and germicides, in electrolytes for batteries, and in electroplating baths. Chemical formula: CuSO ₄ ·5H ₂ O.

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Etymology

Origin of blue vitriol

First recorded in 1760–70

Example Sentences

If he couldn’t get along any other way, he could fill his pockets with brimstone matches, and his boots full of blue vitriol.

From The Witches of New York by Doesticks, Q. K. Philander

"We can use this or take some of the copper ore, that is, the blue vitriol part of the ore, and by putting it in a lime-water solution a beautiful blue color can be obtained."

From The Wonder Island Boys: Exploring the Island by Finlay, Roger Thompson

Absorption from the mucous membrane is increased by opium, and Peruvian bark, internally; and by blue vitriol externally.

From Zoonomia, Vol. II Or, the Laws of Organic Life by Darwin, Erasmus

I have sprayed after the blossom fell, with Paris green, London purple, and blue vitriol; don't know that I reduced the codling-moth any.

From The Apple by Various

When it dissolves in water the molecules of the blue vitriol go wandering out into the spaces between the water molecules.

From Letters of a Radio-Engineer to His Son by Mills, John