Glacial Acetic Acid from Wood Vinegar: Acetate of Soda, Oil of Vitriol and Freezing

Glacial acetic acid is acetic acid so strong it freezes like ice on a cool day. Andrew Ure (1839) describes how the works got it from wood vinegar: turn the acid into acetate of soda, burn the tar out of the salt, set the acid free again with oil of vitriol, distil, and finally freeze it, keeping only what crystallises, until it all congeals at 55 °F (13 °C).