What is to refine or purify by repeated distillation or sublimation, by which the fine parts of a substance are separated from the grosser; as, to rectify spirit of wine called?

rectify — (Chem.) To refine or purify by repeated distillation or sublimation, by which the fine parts of a substance are separated from the grosser; as, to rectify spirit of wine. (Webster's 1913.)

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