from The American Heritage® Dictionary of the English Language, 4th Edition
- n. See ferrous sulfate.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Ferrous sulfate.
from the GNU version of the Collaborative International Dictionary of English
- n. Green vitriol, or sulphate of iron; a green crystalline substance, of an astringent taste, used in making ink, in dyeing black, as a tonic in medicine, etc. It is made on a large scale by the oxidation of iron pyrites. Called also ferrous sulphate.
from The Century Dictionary and Cyclopedia
- n. Green vitriol, the sulphate of iron, or ferrous sulphate, FeSO4.7H2O, a salt of a peculiar astringent taste and of various colors, green, gray, yellowish, or whitish, but more usually green.
Though often a brilliant colored mineral, it is neither gold nor copper; but it may be associated with one or both of them, as found in North Carolina, and it is valuable of itself, being easily converted into copperas, which is sulphate of iron.
Sulphuric acid has also been supposed to be sometimes an ingredient of peat -- which combining with iron, (always present,) would favor sulphate of iron, or copperas, which is a poison to useful plants.
At Walton-under-the-Naze they find on the shore copperas-stone in great quantities; and there are several large works called copperas houses, where they make it with great expense.
Another substance which has been found to have an injurious action is ferrous sulphate or "copperas," a substance which is apt to be present in badly drained soils, or soils in which there is much actively putrefying organic matter.
Other substances also have been examined, such as copperas ores from various parts of the State; numerous specimens supposed to be, or contain, saltpetre, but mostly containing only Epsom or Glauber's Salt.
I drank wine of immoral bouquet: sea foam, midday drizzle, ash of poppies, copperas, mustard.
An odor of copperas issued in puffs from the roofs of the neighboring factory.
The eighteenth-century development of the Saxon blue, or copperas, vat was based on new combinations of ingredients, requiring only slight changes to skills.
Put it into 10 gallons of cold water, and add half a pound of Potash. 1 lb green copperas, 3 lbs quicklime.
The first of these changes was the development of the copperas vat, used in England in the 1730s for solid coloring of cloths as well as the creation of resist patterns. 10 In this process, prepared indigo is added to a mixture of copperas (ferrous sulfate) with lime and potash.