Versailles, 1679, at the apogee of the reign of King Louis XIV, one of the largest and most sordid criminal case of all time breaks out: the affair of the poisons. Love, hatred, greed or jealousy affected all classes of society, including the King's entourage.

The doctors Fresquières and Dugué, as well as the apothecaries Simon and Geoffroy, will be the experts in charge of the medical and toxicological reports of the Chambre Ardente (“burning court”), a special jurisdiction in charge of cases of poisoning and witchcraft, set up on 7th April 1679 by King Louis XIV. The latter wished to shed light on all these criminal attempts, no matter how highly placed the culprits were; on condition that all interrogations involving the most prominent personalities were kept out of the proceedings, as he did not wish to cause a scandal.

Olympe Mancini, one of the young King's first loves, Madame de Montespan, King's ex-favourite, her maid of honour, La Des Oeillets and her chambermaid Catau, or even Nicolas Fouquet's supporters, could all have had their finger on the secret plan to oust the King.

At a time when toxicological science was still in its beginning, poisoners such as La De La Grange, La Bosse, La Voisin, La Filastre and Lesage used arsenic, sulphurous or mercurous compounds, plant or animal poisons to make decoctions, to spice up a glass of wine, to sprinkle beatillis on a pie, to impregnate clothes or to coat paper.

Among their expert opinions, the apothecaries of the Chambre Ardente examined powders of La Filastre, reputed to be “dangerous with a dagger, with poison and in everything”. They found dried menstrual blood, cantharides mixed with two ounces of henbane grains “whose quantity taken internally is very dangerous”, a small bag of blackish powder that they identified as powder of crushed herbs or plants and, in a scapular bound with thread, a small quantity of grey powder whose composition could not be determined. Despite these inconclusive toxicological results, La Filastre was nevertheless found guilty of abortion, infanticide, Satanism and poisoning and was sentenced to death, burned alive at the stake in the Place de Grève.

Madame de Montespan, who was guilty, according to the Lieutenant General of Police, of sacrilege (by participating in diabolical ceremonies), attempted crimes (on the King's new favourite, Madame de Fontange), crimes (by offering newborn babies during black masses) and lèse-majesté (administration of aphrodisiacs and poisoning) but defended by Colbert, left the court in 1691.

In 3 years, after 210 sessions of the Chambre Ardente, 319 decrees of arrest, 194 arrests and 104 judgements including 36 death sentences, on 21st July 1692, the King closed the Chambre de l’Arsenal. On 31st July 1692, the Edict of Colbert and De La Reynie banished soothsayers, diviners and horoscope readers from the Kingdom, severely punished superstitious practices, so-called magic, which was henceforth considered pure charlatanism and sacrilege, regulated the trade in toxic or poisonous products and animals, herbs, snakes, toads and vipers, and reserved the right to have laboratories solely for apothecaries and professors of chemistry.

The affair of the poisons, if it was not the occasion for the fledging of toxicology, at least allowed the foundations to be laid…of the officinal pharmacy!