Plural of alkaly (archaic spelling of alkali); multiple alkaline substances or salts.
From alkali with an archaic or variant plural ending -ies. This represents an older English spelling convention before standardization of alkali/alkalies.
Alkalies shows how English was still figuring out how to pluralize borrowed Arabic words in the 1600s-1700s. Different regions and books used different plurals—it's linguistic anarchy in historical texts!
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