17th century furnace. Engraving of the furnace designed by the German chemist Johann Glauber (1604-70). Used for distillation, this pioneering furnace featured a chimney to promote a draught through it. It allowed substances to be heated to higher temperatures and under a greater range of conditions than ever before. The furnace formed part of the most complicated European chemical laboratory of its time. Glauber distilled a number of chemicals and was the first person to obtain pure hydrochloric acid; Glauber salts (hydrated sodium sulphate) were named after him. Image from Glauber's Furni novi philosophi oder Beschreibung der neu erfunden Distillir-Kunst (1648).