AS LONG AS HUMANS HAVE been alive, they’ve been concerned with the inevitabilities of aging. Today, there’s a universe of razor-specific creams and serums tailor-made for your skin. But back in 16th-century France, people, especially members of the nobility, tried to assuage wrinkles and age spots with a significantly deadlier substance: gold. One such member of the French court, Diane de Poitiers, drank a daily tonic of gold chloride mixed with diethyl ether. It likely killed her.