Glass bottle with a glass stopper that is covered with a piece of leather. White powder inside. Printed label reads "Finest magnesia". Second label reads "Pure condensed calcined magnesia". Magnesium oxide (MgO). An inorganic compound that occurs in nature as the mineral periclase. In aqueous media combines quickly with water to form magnesium hydroxide. It is used as an antacid and mild laxative and has many nonmedicinal uses. Savory 1836, p. 56-8:
“Magnesia, Calcined. – In large doses, magnesia is a gentle purgative, and its employment is always followed with beneficial effects in cases of acidity of the primae viae, observable principally in people who use milk habitually, or after violent violent paroxysms of gout. (…) In small doses, it acts no longer as a laxative, but it is frequently employed in this manner as an antacid, to neutralise the acids formed in the stomach under certain circumstances, and especially in pregnant women and children. Combined with cream of tartar, rhubarb, or Epsom salts, it becomes more active. (…) Calcinated magnesia is also very beneficial in cases of poisoning by acids, on account of the great facility with which they combine with it, and of the harmlessness of the salts resulting from this combination.”