The lieutenant general de police, Gabriel Nicolas de La Reynie, obviously suspects Mademoiselle de la Grange of having had the letter, which intimates that there is a plot to kill the King, forged.  Her aim being to support her “revelations”, while innocenting herself.  She denies it, but four handwriting experts declare that the anonymous letter is definitely in Abbot Nail’s hand.  The two ciminals’ manipulations have fooled no-one, and do not save them from the death penalty:  they are executed on 8 February 1679.


Meanwhile, the Poisons Case has taken on considerable amplitude.  La Reynie senses that it risks leading onto very perilous terrain, and that the “revelations” made to Louvois by the false Widow Faurie are perhaps not entirely fabulations.

But, before coming to these developments, which will permit the tenacious La Reynie to discover an inextricable network of relations and complicities among a few hundred “devineresses” and alchemists who, to the manufacture and sale of poisons, willingly add the professions of money-forger and abortionist, the moment has come for us to take a closer look at the famous “succession powder”, and how it is used.


Arsenic is one of the most used ingredients in the composition of poisons, as its total absence of taste makes it particularly suited to favorising criminal designs.  Whatever its method of introduction into the organism, the same symptoms are always to be seen, and they arrive always in the same order:  gastro-intestinal troubles, laryngic and bronchial catarrhs, rashes, troubling of the senses, motor troubles.  In the case of “most severe” intoxication, vomitting occurs half an hour after the poison’s absorption, followed by a burning thirst with dryness of the mouth and numerous alvine evacuations.  Death can come at the end of twenty-four hours, under the effect of a cardiac syncope, after the victim has given clinical signs close to those of cholera:  weak pulse, tendency to lipothymias, cyanosis of the face, cramps, anuria.  In the forms of intoxication said to be “severe”, death comes later, after six to ten days.  It can then be no longer due to the toxic action of the arsenic, but to the result of problems with the renal and hepatic functions engendered by the poison.

Rarer, but no less redoubtable, sublimate (or mercurical chloride) is also very much in favour, its mortal effect being produced between twenty-four and thirty-six hours after absorption, sometimes in only a few hours, and in certain cases in less than an hour.  Upon ingestion of the poison, a burning sensation spreads through the throat, rapidly reaching the oesophagus and the stomach.  Immediately followed by bilious and bloody vomitting, accompanied by dysentery-type phenomena.  The buccal cavity tumefies, the mucous becomes red and shiny, the breath fetid, while the very abundant salivation sometimes attains several litres, the pulse accelerates and the breathing becomes oppressed.  After a short remission, the extremities of the body become cold and a syncope finishes by leading to death.  In the form of intoxication called “common”, death only occurs after six to ten days.  The symptoms are the same, although of less intensity.  On the other hand, at the end of five or six days, rashes appear, essentially polymorphous, with papulous, squamous, blistering or vesiculous lesions, which are mainly on the internal part of the thighs, on the face or on the wrists.  These symptoms can be fairly easily thought to be from a venereal disease, which is an advantage for wives anxious to rid themselves of their cumbersome husbands, while at the same time ruining their reputations…

Another popular poison:  cantharide powder.  Since Antiquity, this beetle has been known and used for its aphrodisiac properties, but also for its mortal effects.  In his famous Precis de medecine legale, Professor Balthazard has furnished a definitive and truly frightening description of the symptoms of poisoning by cantharides:

“In general, immediately after the ingestion of the poison, the patients feel a sensation of burning in the mouth and throat;  then, after a time, which varies from one to three hours, a sharp pain at the level of the epigastric depression appears.  The patients vomit glairous matters, streaked with blood;  their faces become congested, and they suffer from a violent headache.  At the same time an extreme congestion of the genito-urinary organs is seen, which handicaps the secretion of urine, which provokes, at meatus level, a burning comparable to that of a red-hot iron introduced inside the urethra.  The need to urinate is continual, and leads to the emission of a few drops of urine, rich in albumine and bloody, at the price of very sharp pains.  Diarrhoea is usual, and is accompanied by an anal tenesmus, as painful for the patients as the vesical tenesmus.  At this moment, the agitation is extreme;  sometimes delirious phenomena occur, followed by an attack of contractures similar to those of tetanus;  sometimes an erotic delirium appears which pushes the patients to deliver themselves up to obscene actions.  Nothing can then restrain the venerean desires, nothing can satisfy them;  the priapism is incessant.  Soon, the patients fall exhausted, until another paroxysm shakes them from their torpor and re-ignites their desires.  After a few hours, the attacks cease and the patients fall into a coma, which ends in death after twenty-four to thirty-six hours.”

In the composition of poisons – composition obviously empiric and sometimes even just guesswork, in spite of “trials” effected on animals, or on patients, as in the case of the Marquise de Brinvilliers – there can enter all sorts of other dangerous ingredients such as antimony, vitriol [sulphuric acid], verdigris or diamond powder, venoms from animals or vegetal substances like mandragora, belladonna, rye grass, hemlock or nightshade.  Curiously, the contemporary witnesses seem hardly to mention poisonings by mushrooms.  On the other hand, opium renders such “services” that Antoine Furetiere, in his precious Dictionnaire universel which appears in Holland in 1690, is able to give this precision:

“It is commonly held that only three grains of opium are needed to kill the most robust people.”

Poisoning by opium can effectively take a lightning-fast form, the victim being then plunged into a comatose state right from its absorption, with dilation of the pupils and sometimes convulsions.  Death comes at the end of an agony of at least one hour.


To be continued.