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 zinc and copper are used, the solution is made from water and blue vitriol.

From The Boy Mechanic: Volume 1 700 Things for Boys to Do by Popular Mechanics Co.

Some stuff made in Shoreditch of common blue vitriol and turpentine.

From Punch, or the London Charivari, Volume 98, May 17, 1890. by Various

Sky Blue:—For three pounds of goods, blue vitriol four ounces; boil a few minutes, then dip the goods three hours; then pass them through a strong lime-water.

From The Whitehouse Cookbook (1887) Cooking, Toilet and Household Recipes, Menus, Dinner-Giving, Table Etiquette, Care of the Sick, Health Suggestions, Facts Worth Knowing, Etc., Etc. The Whole Comprising a Comprehensive Cyclopedia of Information for the Home by Gillette, F. L. (Fanny Lemira)

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

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