Poison is frequently referred to as “a woman’s weapon” because it allows murder to be committed from a distance and often requires subterfuge to deploy, which is probably why it doesn’t come as a surprise that women were at the heart of the so-called Affair of the Poisons that plagued Louis XIV’s court from 1677 to 1682.  Both men and women of the court sought out supernatural means to win Louis’s favor. The king’s longtime mistress, Madame de Montespan, was accused of resorting to love spells to keep his affection after childbirth had changed her figure.
The unravelling began with the execution of Madame de Brinvilliers, who was charged with poisoning her father and brothers in order to inherit their estates. She and her accomplice, the Chevalier de Sainte Croix, were alleged to have used Aqua Tofana, a poison that originated in Italy and was sold primarily to women who desired to be rid of their husbands, although other sources point to arsenic being the poison of choice.  de Brinvilliers was executed in 1676 by beheading and burning at the stake.
It’s been written that in her final moments, de Brinvilliers implicated “half the people in town.”  Deaths of courtiers that previously seemed unfortunate but not suspicious were now looked at from a new perspective, jumpstarting an inquiry that would last for years and end in the execution of over thirty people.
The Oracle Glass by Judith Merkle Riley is loosely based on this time period and straddles the line between historical fiction and fantasy fiction. The story is narrated by Genevieve Pasquiers, who later becomes the famed (and fictitious) Marquise de Morville. She describes herself as “an ugly girl who can’t walk right” . Her father educates her in classical languages and philosophy, instruction which leads her to view herself as a woman of logic.
Genevieve’s mother is based on the infamous Madame de Brinvilliers. It was purported that de Brinvilliers and her lover, de Sainte Croix, tested their poisons for the thrill of it, and much like them, Madame de Pasquiers is depicted as poisoning under the guise of charity. de Pasquiers and the woman she’s based upon are arguably psychopaths, as they need little encouragement to take a life beyond the prospect of their own pleasure.
When Genevieve’s mother poisons her husband and mother-in-law, Genevieve’s uncle assaults her in an effort to take her inheritance. Genevieve vows to avenge herself and her father, runs away, and crosses paths with La Voisin, a historical figure and, supposedly, a witch. La Voisin promises Genevieve, who can truly see the future by looking in an orb of water, to make her “strong enough to destroy” her uncle and transforms her into the Marquise de Morville, a 150-year-old fortune teller.  Fortune-telling allows Genevieve to support herself as well as repay La Voisin for the education. Although Genevieve focuses on fortune-telling and leaves the poisoning to La Voisin, she’s also determined to get revenge on her uncle, and she can’t escape getting caught up in the Affair of the Poisons.
As a doctor treats Genevieve for a broken arm, he correctly guesses she’d been injured by a man and says, “If it had been one of your witches, now, you wouldn’t have lived out the week, and there wouldn’t be a mark to show.”  The implication is that patience, thought to be one of women’s primary virtues, can also aid in immorality, for women are patient enough to wait for an opportune time to slip poison into a drink, to wait for a note covered in poison to be delivered, to wait for poison to take effect.
The Oracle Glass presents a variety of women who murder for a variety of reasons—for personal pleasure, for societal advancement, for money, for revenge. In real life, these women intrigue us because they’re statistically less likely to commit murder than men. Fiction allows us to explore the motivations behind such crimes and offers a means of coping with the fact that, in real life, there are often no easy answers.
 Frost, Natasha. “The Scandalous Witch Hunt That Poisoned 17th-Century France.” Atlas Obscura, 05 Oct. 2017. https://www.atlasobscura.com/articles/affair-of-the-poisons-france-witch-hunt-occult
 Duramy, Benedetta F. “Catherine La Voison: Poisons and Magic at the Royal Court of Louis XIV.” Toxicology in the Middle Ages and Renaissance, edited by Philip Wexler. Academic Press, London, UK. 2017. 135-140.
 Riley, Judith Merkle. The Oracle Glass. Sourcebooks, Illinois, 2012.